This solution provides a strict FixedLengthArray (ak.a. SealedArray) type signature based in Tuples.
Syntax example :
// Array containing 3 strings
let foo : FixedLengthArray<[string, string, string]>
This is the safest approach, considering it prevents accessing indexes out of the boundaries.
Implementation :
type ArrayLengthMutationKeys = 'splice' | 'push' | 'pop' | 'shift' | 'unshift' | number
type ArrayItems<T extends Array<any>> = T extends Array<infer TItems> ? TItems : never
type FixedLengthArray<T extends any[]> =
Pick<T, Exclude<keyof T, ArrayLengthMutationKeys>>
& { [Symbol.iterator]: () => IterableIterator< ArrayItems<T> > }
Tests :
var myFixedLengthArray: FixedLengthArray< [string, string, string]>
// Array declaration tests
myFixedLengthArray = [ 'a', 'b', 'c' ] // ? OK
myFixedLengthArray = [ 'a', 'b', 123 ] // ? TYPE ERROR
myFixedLengthArray = [ 'a' ] // ? LENGTH ERROR
myFixedLengthArray = [ 'a', 'b' ] // ? LENGTH ERROR
// Index assignment tests
myFixedLengthArray[1] = 'foo' // ? OK
myFixedLengthArray[1000] = 'foo' // ? INVALID INDEX ERROR
// Methods that mutate array length
myFixedLengthArray.push('foo') // ? MISSING METHOD ERROR
myFixedLengthArray.pop() // ? MISSING METHOD ERROR
// Direct length manipulation
myFixedLengthArray.length = 123 // ? READ-ONLY ERROR
// Destructuring
var [ a ] = myFixedLengthArray // ? OK
var [ a, b ] = myFixedLengthArray // ? OK
var [ a, b, c ] = myFixedLengthArray // ? OK
var [ a, b, c, d ] = myFixedLengthArray // ? INVALID INDEX ERROR
(*) This solution requires the noImplicitAny
typescript configuration directive to be enabled in order to work (commonly recommended practice)
This solution behaves as an augmentation of the Array
type, accepting an additional second parameter(Array length). Is not as strict and safe as the Tuple based solution.
Syntax example :
let foo: FixedLengthArray<string, 3>
Keep in mind that this approach will not prevent you from accessing an index out of the declared boundaries and set a value on it.
Implementation :
type ArrayLengthMutationKeys = 'splice' | 'push' | 'pop' | 'shift' | 'unshift'
type FixedLengthArray<T, L extends number, TObj = [T, ...Array<T>]> =
Pick<TObj, Exclude<keyof TObj, ArrayLengthMutationKeys>>
& {
readonly length: L
[ I : number ] : T
[Symbol.iterator]: () => IterableIterator<T>
}
Tests :
var myFixedLengthArray: FixedLengthArray<string,3>
// Array declaration tests
myFixedLengthArray = [ 'a', 'b', 'c' ] // ? OK
myFixedLengthArray = [ 'a', 'b', 123 ] // ? TYPE ERROR
myFixedLengthArray = [ 'a' ] // ? LENGTH ERROR
myFixedLengthArray = [ 'a', 'b' ] // ? LENGTH ERROR
// Index assignment tests
myFixedLengthArray[1] = 'foo' // ? OK
myFixedLengthArray[1000] = 'foo' // ? SHOULD FAIL
// Methods that mutate array length
myFixedLengthArray.push('foo') // ? MISSING METHOD ERROR
myFixedLengthArray.pop() // ? MISSING METHOD ERROR
// Direct length manipulation
myFixedLengthArray.length = 123 // ? READ-ONLY ERROR
// Destructuring
var [ a ] = myFixedLengthArray // ? OK
var [ a, b ] = myFixedLengthArray // ? OK
var [ a, b, c ] = myFixedLengthArray // ? OK
var [ a, b, c, d ] = myFixedLengthArray // ? SHOULD FAIL
sys.dm_exec_connections
uses varchar(48) after SQL Server 2005 SP1. Sounds good enough for me especially if you want to use it compare to your value.
Realistically, you won't see IPv6 as mainstream for a while yet, so I'd prefer the 4 tinyint route. Saying that, I'm using varchar(48) because I have to use sys.dm_exec_connections
...
Otherwise. Mark Redman's answer mentions a previous SO debate question.
as HTMLInputElement
works for me
Simpler with OUT
parameters:
CREATE OR REPLACE FUNCTION get_object_fields(_school_id int
, OUT user1_id int
, OUT user1_name varchar(32)
, OUT user2_id int
, OUT user2_name varchar(32)) AS
$func$
BEGIN
SELECT INTO user1_id, user1_name
u.id, u.name
FROM users u
WHERE u.school_id = _school_id
LIMIT 1; -- make sure query returns 1 row - better in a more deterministic way?
user2_id := user1_id + 1; -- some calculation
SELECT INTO user2_name
u.name
FROM users u
WHERE u.id = user2_id;
END
$func$ LANGUAGE plpgsql;
Call:
SELECT * FROM get_object_fields(1);
You don't need to create a type just for the sake of this plpgsql function. It may be useful if you want to bind multiple functions to the same composite type. Else, OUT
parameters do the job.
There is no RETURN
statement. OUT
parameters are returned automatically with this form that returns a single row. RETURN
is optional.
Since OUT
parameters are visible everywhere inside the function body (and can be used just like any other variable), make sure to table-qualify columns of the same name to avoid naming conflicts! (Better yet, use distinct names to begin with.)
Typically, this can be simpler and faster if queries in the function body can be combined. And you can use RETURNS TABLE()
(since Postgres 8.4, long before the question was asked) to return 0-n rows.
The example from above can be written as:
CREATE OR REPLACE FUNCTION get_object_fields2(_school_id int)
RETURNS TABLE (user1_id int
, user1_name varchar(32)
, user2_id int
, user2_name varchar(32)) AS
$func$
BEGIN
RETURN QUERY
SELECT u1.id, u1.name, u2.id, u2.name
FROM users u1
JOIN users u2 ON u2.id = u1.id + 1
WHERE u1.school_id = _school_id
LIMIT 1; -- may be optional
END
$func$ LANGUAGE plpgsql;
Call:
SELECT * FROM get_object_fields2(1);
RETURNS TABLE
is effectively the same as having a bunch of OUT
parameters combined with RETURNS SETOF record
, just shorter.
The major difference: this function can return 0, 1 or many rows, while the first version always returns 1 row.
Add LIMIT 1
like demonstrated to only allow 0 or 1 row.
RETURN QUERY
is simple way to return results from a query directly.
You can use multiple instances in a single function to add more rows to the output.
db<>fiddle here (demonstrating both)
If your function is supposed to dynamically return results with a different row-type depending on the input, read more here:
Let's break this down:
The error says
Cannot invoke an expression whose type lacks a call signature.
The code:
The problem is in this line public toggleBody: string;
&
it's relation to these lines:
...
return this.toggleBody(true);
...
return this.toggleBody(false);
Your saying toggleBody
is a string
but then your treating it like something that has a call signature
(i.e. the structure of something that can be called: lambdas, proc, functions, methods, etc. In JS just function tho.). You need to change the declaration to be public toggleBody: (arg: boolean) => boolean;
.
Extra Details:
"invoke" means your calling or applying a function.
"an expression" in Javascript is basically something that produces a value, so this.toggleBody()
counts as an expression.
"type" is declared on this line public toggleBody: string
"lacks a call signature" this is because your trying to call something this.toggleBody()
that doesn't have signature(i.e. the structure of something that can be called: lambdas, proc, functions, methods, etc.) that can be called. You said this.toggleBody
is something that acts like a string.
In other words the error is saying
Cannot call an expression (this.toggleBody) because it's type (:string) lacks a call signature (bc it has a string signature.)
The point about generics is to give compile-time type safety - which means that types need to be known at compile-time.
You can call generic methods with types only known at execution time, but you have to use reflection:
// For non-public methods, you'll need to specify binding flags too
MethodInfo method = GetType().GetMethod("DoesEntityExist")
.MakeGenericMethod(new Type[] { t });
method.Invoke(this, new object[] { entityGuid, transaction });
Ick.
Can you make your calling method generic instead, and pass in your type parameter as the type argument, pushing the decision one level higher up the stack?
If you could give us more information about what you're doing, that would help. Sometimes you may need to use reflection as above, but if you pick the right point to do it, you can make sure you only need to do it once, and let everything below that point use the type parameter in a normal way.
You usually want to use NSInteger
when you don't know what kind of processor architecture your code might run on, so you may for some reason want the largest possible integer type, which on 32 bit systems is just an int
, while on a 64-bit system it's a long
.
I'd stick with using NSInteger
instead of int
/long
unless you specifically require them.
NSInteger
/NSUInteger
are defined as *dynamic typedef
*s to one of these types, and they are defined like this:
#if __LP64__ || TARGET_OS_EMBEDDED || TARGET_OS_IPHONE || TARGET_OS_WIN32 || NS_BUILD_32_LIKE_64
typedef long NSInteger;
typedef unsigned long NSUInteger;
#else
typedef int NSInteger;
typedef unsigned int NSUInteger;
#endif
With regard to the correct format specifier you should use for each of these types, see the String Programming Guide's section on Platform Dependencies
Performance test typeof() vs GetType():
using System;
namespace ConsoleApplication1
{
class Program
{
enum TestEnum { E1, E2, E3 }
static void Main(string[] args)
{
{
var start = DateTime.UtcNow;
for (var i = 0; i < 1000000000; i++)
Test1(TestEnum.E2);
Console.WriteLine(DateTime.UtcNow - start);
}
{
var start = DateTime.UtcNow;
for (var i = 0; i < 1000000000; i++)
Test2(TestEnum.E2);
Console.WriteLine(DateTime.UtcNow - start);
}
Console.ReadLine();
}
static Type Test1<T>(T value) => typeof(T);
static Type Test2(object value) => value.GetType();
}
}
Results in debug mode:
00:00:08.4096636
00:00:10.8570657
Results in release mode:
00:00:02.3799048
00:00:07.1797128
Historically, 255 characters has often been the maximum length of a VARCHAR
in some DBMSes, and it sometimes still winds up being the effective maximum if you want to use UTF-8 and have the column indexed (because of index length limitations).
Apparently, no.
Here's the options:
is
and as
As you've already found out, this will not work if the two types are the same, here's a sample LINQPad program that demonstrates:
void Main()
{
typeof(Derived).IsSubclassOf(typeof(Base)).Dump();
typeof(Base).IsSubclassOf(typeof(Base)).Dump();
}
public class Base { }
public class Derived : Base { }
Output:
True
False
Which indicates that Derived
is a subclass of Base
, but that Base
is (obviously) not a subclass of itself.
Now, this will answer your particular question, but it will also give you false positives. As Eric Lippert has pointed out in the comments, while the method will indeed return True
for the two above questions, it will also return True
for these, which you probably don't want:
void Main()
{
typeof(Base).IsAssignableFrom(typeof(Derived)).Dump();
typeof(Base).IsAssignableFrom(typeof(Base)).Dump();
typeof(int[]).IsAssignableFrom(typeof(uint[])).Dump();
}
public class Base { }
public class Derived : Base { }
Here you get the following output:
True
True
True
The last True
there would indicate, if the method only answered the question asked, that uint[]
inherits from int[]
or that they're the same type, which clearly is not the case.
So IsAssignableFrom
is not entirely correct either.
is
and as
The "problem" with is
and as
in the context of your question is that they will require you to operate on the objects and write one of the types directly in code, and not work with Type
objects.
In other words, this won't compile:
SubClass is BaseClass
^--+---^
|
+-- need object reference here
nor will this:
typeof(SubClass) is typeof(BaseClass)
^-------+-------^
|
+-- need type name here, not Type object
nor will this:
typeof(SubClass) is BaseClass
^------+-------^
|
+-- this returns a Type object, And "System.Type" does not
inherit from BaseClass
While the above methods might fit your needs, the only correct answer to your question (as I see it) is that you will need an extra check:
typeof(Derived).IsSubclassOf(typeof(Base)) || typeof(Derived) == typeof(Base);
which of course makes more sense in a method:
public bool IsSameOrSubclass(Type potentialBase, Type potentialDescendant)
{
return potentialDescendant.IsSubclassOf(potentialBase)
|| potentialDescendant == potentialBase;
}
One of the difference is Null termination (\0).
In C and C++, char* or char[] will take a pointer to a single char as a parameter and will track along the memory until a 0 memory value is reached (often called the null terminator).
C++ strings can contain embedded \0 characters, know their length without counting.
#include<stdio.h>
#include<string.h>
#include<iostream>
using namespace std;
void NullTerminatedString(string str){
int NUll_term = 3;
str[NUll_term] = '\0'; // specific character is kept as NULL in string
cout << str << endl <<endl <<endl;
}
void NullTerminatedChar(char *str){
int NUll_term = 3;
str[NUll_term] = 0; // from specific, all the character are removed
cout << str << endl;
}
int main(){
string str = "Feels Happy";
printf("string = %s\n", str.c_str());
printf("strlen = %d\n", strlen(str.c_str()));
printf("size = %d\n", str.size());
printf("sizeof = %d\n", sizeof(str)); // sizeof std::string class and compiler dependent
NullTerminatedString(str);
char str1[12] = "Feels Happy";
printf("char[] = %s\n", str1);
printf("strlen = %d\n", strlen(str1));
printf("sizeof = %d\n", sizeof(str1)); // sizeof char array
NullTerminatedChar(str1);
return 0;
}
Output:
strlen = 11
size = 11
sizeof = 32
Fee s Happy
strlen = 11
sizeof = 12
Fee
Your description is a little confusing.
Generally speaking, though some C++ implementations have mechanisms for it, you're not supposed to ask about the type. Instead, you are supposed to do a dynamic_cast on the pointer to A. What this will do is that at runtime, the actual contents of the pointer to A will be checked. If you have a B, you'll get your pointer to B. Otherwise, you'll get an exception or null.
Unsigned int can be converted to signed (or vice-versa) by simple expression as shown below :
unsigned int z;
int y=5;
z= (unsigned int)y;
Though not targeted to the question, you would like to read following links :
Button won't submit form on its own.It is a simple button which is used to perform some operation by using javascript whereas Submit is a kind of button which by default submit the form whenever user clicks on submit button.
The differences are covered at the PostgreSQL documentation for date/time types. Yes, the treatment of TIME
or TIMESTAMP
differs between one WITH TIME ZONE
or WITHOUT TIME ZONE
. It doesn't affect how the values are stored; it affects how they are interpreted.
The effects of time zones on these data types is covered specifically in the docs. The difference arises from what the system can reasonably know about the value:
With a time zone as part of the value, the value can be rendered as a local time in the client.
Without a time zone as part of the value, the obvious default time zone is UTC, so it is rendered for that time zone.
The behaviour differs depending on at least three factors:
WITH TIME ZONE
or WITHOUT TIME ZONE
) of the value.Here are examples covering the combinations of those factors:
foo=> SET TIMEZONE TO 'Japan';
SET
foo=> SELECT '2011-01-01 00:00:00'::TIMESTAMP;
timestamp
---------------------
2011-01-01 00:00:00
(1 row)
foo=> SELECT '2011-01-01 00:00:00'::TIMESTAMP WITH TIME ZONE;
timestamptz
------------------------
2011-01-01 00:00:00+09
(1 row)
foo=> SELECT '2011-01-01 00:00:00+03'::TIMESTAMP;
timestamp
---------------------
2011-01-01 00:00:00
(1 row)
foo=> SELECT '2011-01-01 00:00:00+03'::TIMESTAMP WITH TIME ZONE;
timestamptz
------------------------
2011-01-01 06:00:00+09
(1 row)
foo=> SET TIMEZONE TO 'Australia/Melbourne';
SET
foo=> SELECT '2011-01-01 00:00:00'::TIMESTAMP;
timestamp
---------------------
2011-01-01 00:00:00
(1 row)
foo=> SELECT '2011-01-01 00:00:00'::TIMESTAMP WITH TIME ZONE;
timestamptz
------------------------
2011-01-01 00:00:00+11
(1 row)
foo=> SELECT '2011-01-01 00:00:00+03'::TIMESTAMP;
timestamp
---------------------
2011-01-01 00:00:00
(1 row)
foo=> SELECT '2011-01-01 00:00:00+03'::TIMESTAMP WITH TIME ZONE;
timestamptz
------------------------
2011-01-01 08:00:00+11
(1 row)
From the friendly Wikipedia:
The stdlib.h and stddef.h header files define a datatype called size_t which is used to represent the size of an object. Library functions that take sizes expect them to be of type size_t, and the sizeof operator evaluates to size_t.
The actual type of size_t is platform-dependent; a common mistake is to assume size_t is the same as unsigned int, which can lead to programming errors, particularly as 64-bit architectures become more prevalent.
Also, check Why size_t matters
a.getClass().getName()
Like that:
class Zoo {
AnimalClass: typeof Animal;
constructor(AnimalClass: typeof Animal ) {
this.AnimalClass = AnimalClass
let Hector = new AnimalClass();
}
}
Or just:
class Zoo {
constructor(public AnimalClass: typeof Animal ) {
let Hector = new AnimalClass();
}
}
typeof Class
is the type of the class constructor. It's preferable to the custom constructor type declaration because it processes static class members properly.
Here's the relevant part of TypeScript docs. Search for the typeof
. As a part of a TypeScript type annotation, it means "give me the type of the symbol called Animal" which is the type of the class constructor function in our case.
You could always use something like mktime to create a known time (midnight, last night) and use difftime to get a double-precision time difference between the two. For a platform-independant solution, unless you go digging into the details of your libraries, you're not going to do much better than that. According to the C spec, the definition of time_t is implementation-defined (meaning that each implementation of the library can define it however they like, as long as library functions with use it behave according to the spec.)
That being said, the size of time_t on my linux machine is 8 bytes, which suggests a long int or a double. So I did:
int main()
{
for(;;)
{
printf ("%ld\n", time(NULL));
printf ("%f\n", time(NULL));
sleep(1);
}
return 0;
}
The time given by the %ld increased by one each step and the float printed 0.000 each time. If you're hell-bent on using printf to display time_ts, your best bet is to try your own such experiment and see how it work out on your platform and with your compiler.
Number.prototype.toFixed
is a function designed to format a number before printing it out. It's from the family of toString
, toExponential
and toPrecision
.
To round a number, you would do this:
someNumber = 42.008;
someNumber = Math.round( someNumber * 1e2 ) / 1e2;
someNumber === 42.01;
// if you need 3 digits, replace 1e2 with 1e3 etc.
// or just copypaste this function to your code:
function toFixedNumber(num, digits, base){
var pow = Math.pow(base||10, digits);
return Math.round(num*pow) / pow;
}
.
Or if you want a “native-like” function, you can extend the prototype:
Number.prototype.toFixedNumber = function(digits, base){
var pow = Math.pow(base||10, digits);
return Math.round(this*pow) / pow;
}
someNumber = 42.008;
someNumber = someNumber.toFixedNumber(2);
someNumber === 42.01;
//or even hexadecimal
someNumber = 0xAF309/256 //which is af3.09
someNumber = someNumber.toFixedNumber(1, 16);
someNumber.toString(16) === "af3.1";
However, bear in mind that polluting the prototype is considered bad when you're writing a module, as modules shouldn't have any side effects. So, for a module, use the first function.
The typeof operator...
typeof(T)
... won't work with the c# switch statement. But how about this? The following post contains a static class...
Is there a better alternative than this to 'switch on type'?
...that will let you write code like this:
TypeSwitch.Do(
sender,
TypeSwitch.Case<Button>(() => textBox1.Text = "Hit a Button"),
TypeSwitch.Case<CheckBox>(x => textBox1.Text = "Checkbox is " + x.Checked),
TypeSwitch.Default(() => textBox1.Text = "Not sure what is hovered over"));
Maybe not safe and pretty but if you must:
class string
{
private $Text;
public function __construct($value)
{
$this->Text = $value;
}
public function __toString()
{
return $this->Text;
}
}
function Test123(string $s)
{
echo $s;
}
Test123(new string("Testing"));
try this! it worked for me even if I input negative numbers.
def length(s):
return len(s)
s = input("Enter the String: ")
try:
if (type(int(s)))==int :
print("You input an integer")
except ValueError:
print("it is a string with length " + str(length(s)))
To determine the class of an object simply call:
someObject.getClass()
You can abbreviate this to someObject.class
in most cases. However, if you use this on a Map
it will try to retrieve the value with key 'class'. Because of this, I always use getClass()
even though it's a little longer.
If you want to check if an object implements a particular interface or extends a particular class (e.g. Date) use:
(somObject instanceof Date)
or to check if the class of an object is exactly a particular class (not a subclass of it), use:
(somObject.getClass() == Date)
There is no difference, under the hood it's all varlena
(variable length array).
Check this article from Depesz: http://www.depesz.com/index.php/2010/03/02/charx-vs-varcharx-vs-varchar-vs-text/
A couple of highlights:
To sum it all up:
- char(n) – takes too much space when dealing with values shorter than
n
(pads them ton
), and can lead to subtle errors because of adding trailing spaces, plus it is problematic to change the limit- varchar(n) – it's problematic to change the limit in live environment (requires exclusive lock while altering table)
- varchar – just like text
- text – for me a winner – over (n) data types because it lacks their problems, and over varchar – because it has distinct name
The article does detailed testing to show that the performance of inserts and selects for all 4 data types are similar. It also takes a detailed look at alternate ways on constraining the length when needed. Function based constraints or domains provide the advantage of instant increase of the length constraint, and on the basis that decreasing a string length constraint is rare, depesz concludes that one of them is usually the best choice for a length limit.
I do this in my testcases.
def assertIsIterable(self, item):
#add types here you don't want to mistake as iterables
if isinstance(item, basestring):
raise AssertionError("type %s is not iterable" % type(item))
#Fake an iteration.
try:
for x in item:
break;
except TypeError:
raise AssertionError("type %s is not iterable" % type(item))
Untested on generators, I think you are left at the next 'yield' if passed in a generator, which may screw things up downstream. But then again, this is a 'unittest'
The difference is that the uint
and ulong
are unsigned data types, meaning the range is different: They do not accept negative values:
int range: -2,147,483,648 to 2,147,483,647
uint range: 0 to 4,294,967,295
long range: –9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
ulong range: 0 to 18,446,744,073,709,551,615
the symbol ? after the int means that it can be nullable.
The ? symbol is usually used in situations whereby the variable can accept a null or an integer or alternatively, return an integer or null.
Hope the context of usage helps. In this way you are not restricted to solely dealing with integers.
Update: Simply using a hash function is not strong enough for storing passwords. You should read the answer from Gilles on this thread for a more detailed explanation.
For passwords, use a key-strengthening hash algorithm like Bcrypt or Argon2i. For example, in PHP, use the password_hash() function, which uses Bcrypt by default.
$hash = password_hash("rasmuslerdorf", PASSWORD_DEFAULT);
The result is a 60-character string similar to the following (but the digits will vary, because it generates a unique salt).
$2y$10$.vGA1O9wmRjrwAVXD98HNOgsNpDczlqm3Jq7KnEd1rVAGv3Fykk1a
Use the SQL data type CHAR(60)
to store this encoding of a Bcrypt hash. Note this function doesn't encode as a string of hexadecimal digits, so we can't as easily unhex it to store in binary.
Other hash functions still have uses, but not for storing passwords, so I'll keep the original answer below, written in 2008.
It depends on the hashing algorithm you use. Hashing always produces a result of the same length, regardless of the input. It is typical to represent the binary hash result in text, as a series of hexadecimal digits. Or you can use the UNHEX()
function to reduce a string of hex digits by half.
As of 2015, NIST recommends using SHA-256 or higher for any applications of hash functions requiring interoperability. But NIST does not recommend using these simple hash functions for storing passwords securely.
Lesser hashing algorithms have their uses (like internal to an application, not for interchange), but they are known to be crackable.
Since IPv4 addresses are 4 byte long, you could use an INT
(UNSIGNED
) that has exactly 4 bytes:
`ipv4` INT UNSIGNED
And INET_ATON
and INET_NTOA
to convert them:
INSERT INTO `table` (`ipv4`) VALUES (INET_ATON("127.0.0.1"));
SELECT INET_NTOA(`ipv4`) FROM `table`;
For IPv6 addresses you could use a BINARY
instead:
`ipv6` BINARY(16)
And use PHP’s inet_pton
and inet_ntop
for conversion:
'INSERT INTO `table` (`ipv6`) VALUES ("'.mysqli_real_escape_string(inet_pton('2001:4860:a005::68')).'")'
'SELECT `ipv6` FROM `table`'
$ipv6 = inet_pton($row['ipv6']);
Has to be more complex test if you really want to handle just about anything as function argument.
type(a) != type('') and hasattr(a, "__iter__")
Although, usually it's enough to just spell out that a function expects iterable and then check only type(a) != type('')
.
Also it may happen that for a string you have a simple processing path or you are going to be nice and do a split etc., so you don't want to yell at strings and if someone sends you something weird, just let him have an exception.
Your function has a couple of smallint
parameters.
But in the call, you are using numeric literals that are presumed to be type integer
.
A string literal or string constant ('123'
) is not typed immediately. It remains type "unknown" until assigned or cast explicitly.
However, a numeric literal or numeric constant is typed immediately. Per documentation:
A numeric constant that contains neither a decimal point nor an exponent is initially presumed to be type
integer
if its value fits in typeinteger
(32 bits); otherwise it is presumed to be typebigint
if its value fits in typebigint
(64 bits); otherwise it is taken to be typenumeric
. Constants that contain decimal points and/or exponents are always initially presumed to be typenumeric
.
More explanation and links in this related answer:
Add explicit casts for the smallint
parameters or quote them.
CREATE OR REPLACE FUNCTION f_typetest(smallint)
RETURNS bool AS 'SELECT TRUE' LANGUAGE sql;
Incorrect call:
SELECT * FROM f_typetest(1);
Correct calls:
SELECT * FROM f_typetest('1');
SELECT * FROM f_typetest(smallint '1');
SELECT * FROM f_typetest(1::int2);
SELECT * FROM f_typetest('1'::int2);
db<>fiddle here
Old sqlfiddle.
Use isinstance(obj, basestring)
for an object-to-test obj
.
Docs.
check out one of the simple way to do this
// Read string from console
string line = Console.ReadLine();
int valueInt;
float valueFloat;
if (int.TryParse(line, out valueInt)) // Try to parse the string as an integer
{
Console.Write("This input is of type Integer.");
}
else if (float.TryParse(line, out valueFloat))
{
Console.Write("This input is of type Float.");
}
else
{
Console.WriteLine("This input is of type string.");
}
New answer after 6 years and 5 months (procrastination).
While string
is a reserved C# keyword that always has a fixed meaning, String
is just an ordinary identifier which could refer to anything. Depending on members of the current type, the current namespace and the applied using
directives and their placement, String
could be a value or a type distinct from global::System.String
.
I shall provide two examples where using
directives will not help.
First, when String
is a value of the current type (or a local variable):
class MySequence<TElement>
{
public IEnumerable<TElement> String { get; set; }
void Example()
{
var test = String.Format("Hello {0}.", DateTime.Today.DayOfWeek);
}
}
The above will not compile because IEnumerable<>
does not have a non-static member called Format
, and no extension methods apply. In the above case, it may still be possible to use String
in other contexts where a type is the only possibility syntactically. For example String local = "Hi mum!";
could be OK (depending on namespace and using
directives).
Worse: Saying String.Concat(someSequence)
will likely (depending on using
s) go to the Linq extension method Enumerable.Concat
. It will not go to the static method string.Concat
.
Secondly, when String
is another type, nested inside the current type:
class MyPiano
{
protected class String
{
}
void Example()
{
var test1 = String.Format("Hello {0}.", DateTime.Today.DayOfWeek);
String test2 = "Goodbye";
}
}
Neither statement in the Example
method compiles. Here String
is always a piano string, MyPiano.String
. No member (static
or not) Format
exists on it (or is inherited from its base class). And the value "Goodbye"
cannot be converted into it.
The auto keyword is an important and frequently used keyword for C ++.When initializing a variable, auto keyword is used for type inference(also called type deduction).
There are 3 different rules regarding the auto keyword.
auto x = expr;
----> No pointer or reference, only variable name. In this case, const and reference are ignored.
int y = 10;
int& r = y;
auto x = r; // The type of variable x is int. (Reference Ignored)
const int y = 10;
auto x = y; // The type of variable x is int. (Const Ignored)
int y = 10;
const int& r = y;
auto x = r; // The type of variable x is int. (Both const and reference Ignored)
const int a[10] = {};
auto x = a; // x is const int *. (Array to pointer conversion)
Note : When the name defined by auto is given a value with the name of a function,
the type inference will be done as a function pointer.
auto& y = expr;
or auto* y = expr;
----> Reference or pointer after auto keyword.
Warning : const is not ignored in this rule !!! .
int y = 10;
auto& x = y; // The type of variable x is int&.
Warning : In this rule, array to pointer conversion (array decay) does not occur !!!.
auto& x = "hello"; // The type of variable x is const char [6].
static int x = 10;
auto y = x; // The variable y is not static.Because the static keyword is not a type. specifier
// The type of variable x is int.
auto&& z = expr;
----> This is not a Rvalue reference.
Warning : If the type inference is in question and the && token is used, the names introduced like this are called "Forwarding Reference" (also called Universal Reference).
auto&& r1 = x; // The type of variable r1 is int&.Because x is Lvalue expression.
auto&& r2 = x+y; // The type of variable r2 is int&&.Because x+y is PRvalue expression.
MySQL does not have internal boolean data type. It uses the smallest integer data type - TINYINT.
The BOOLEAN and BOOL are equivalents of TINYINT(1), because they are synonyms.
Try to create this table -
CREATE TABLE table1 (
column1 BOOLEAN DEFAULT NULL
);
Then run SHOW CREATE TABLE, you will get this output -
CREATE TABLE `table1` (
`column1` tinyint(1) DEFAULT NULL
)
Maybe this is going a bit too far back but…
Also, I’d like to suggest that multiline text fields have a different type (e.g. “textarea") than single-line fields ("text"), as they really are different types of things, and imply different issues (semantics) for client-side handling.
I had a similar question, so I worked up a complete runnable answer below. What I needed to do is pass a class (C) to an object (O) of an unrelated class and have that object (O) emit new objects of class (C) back to me when I asked for them.
The example below shows how this is done. There is a MagicGun class that you load with any subtype of the Projectile class (Pebble, Bullet or NuclearMissle). The interesting is you load it with subtypes of Projectile, but not actual objects of that type. The MagicGun creates the actual object when it's time to shoot.
You've annoyed the target!
You've holed the target!
You've obliterated the target!
click
click
import java.util.ArrayList;
import java.util.List;
public class PassAClass {
public static void main(String[] args) {
MagicGun gun = new MagicGun();
gun.loadWith(Pebble.class);
gun.loadWith(Bullet.class);
gun.loadWith(NuclearMissle.class);
//gun.loadWith(Object.class); // Won't compile -- Object is not a Projectile
for(int i=0; i<5; i++){
try {
String effect = gun.shoot().effectOnTarget();
System.out.printf("You've %s the target!\n", effect);
} catch (GunIsEmptyException e) {
System.err.printf("click\n");
}
}
}
}
class MagicGun {
/**
* projectiles holds a list of classes that extend Projectile. Because of erasure, it
* can't hold be a List<? extends Projectile> so we need the SuppressWarning. However
* the only way to add to it is the "loadWith" method which makes it typesafe.
*/
private @SuppressWarnings("rawtypes") List<Class> projectiles = new ArrayList<Class>();
/**
* Load the MagicGun with a new Projectile class.
* @param projectileClass The class of the Projectile to create when it's time to shoot.
*/
public void loadWith(Class<? extends Projectile> projectileClass){
projectiles.add(projectileClass);
}
/**
* Shoot the MagicGun with the next Projectile. Projectiles are shot First In First Out.
* @return A newly created Projectile object.
* @throws GunIsEmptyException
*/
public Projectile shoot() throws GunIsEmptyException{
if (projectiles.isEmpty())
throw new GunIsEmptyException();
Projectile projectile = null;
// We know it must be a Projectile, so the SuppressWarnings is OK
@SuppressWarnings("unchecked") Class<? extends Projectile> projectileClass = projectiles.get(0);
projectiles.remove(0);
try{
// http://www.java2s.com/Code/Java/Language-Basics/ObjectReflectioncreatenewinstance.htm
projectile = projectileClass.newInstance();
} catch (InstantiationException e) {
System.err.println(e);
} catch (IllegalAccessException e) {
System.err.println(e);
}
return projectile;
}
}
abstract class Projectile {
public abstract String effectOnTarget();
}
class Pebble extends Projectile {
@Override public String effectOnTarget() {
return "annoyed";
}
}
class Bullet extends Projectile {
@Override public String effectOnTarget() {
return "holed";
}
}
class NuclearMissle extends Projectile {
@Override public String effectOnTarget() {
return "obliterated";
}
}
class GunIsEmptyException extends Exception {
private static final long serialVersionUID = 4574971294051632635L;
}
Just use print(*(dict.keys()))
The * can be used for unpacking containers e.g. lists. For more info on * check this SO answer.
For small data frames:
library(tidyverse)
as_tibble(mtcars)
gives you a print out of the df with data types
# A tibble: 32 x 11
mpg cyl disp hp drat wt qsec vs am gear carb
* <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 21 6 160 110 3.9 2.62 16.5 0 1 4 4
2 21 6 160 110 3.9 2.88 17.0 0 1 4 4
3 22.8 4 108 93 3.85 2.32 18.6 1 1 4 1
For large data frames:
glimpse(mtcars)
gives you a structured view of data types:
Observations: 32
Variables: 11
$ mpg <dbl> 21.0, 21.0, 22.8, 21.4, 18.7, 18.1, 14.3, 24.4, 22.8, 19.2, 17.8, 16.4, 17....
$ cyl <dbl> 6, 6, 4, 6, 8, 6, 8, 4, 4, 6, 6, 8, 8, 8, 8, 8, 8, 4, 4, 4, 4, 8, 8, 8, 8, ...
$ disp <dbl> 160.0, 160.0, 108.0, 258.0, 360.0, 225.0, 360.0, 146.7, 140.8, 167.6, 167.6...
$ hp <dbl> 110, 110, 93, 110, 175, 105, 245, 62, 95, 123, 123, 180, 180, 180, 205, 215...
$ drat <dbl> 3.90, 3.90, 3.85, 3.08, 3.15, 2.76, 3.21, 3.69, 3.92, 3.92, 3.92, 3.07, 3.0...
$ wt <dbl> 2.620, 2.875, 2.320, 3.215, 3.440, 3.460, 3.570, 3.190, 3.150, 3.440, 3.440...
$ qsec <dbl> 16.46, 17.02, 18.61, 19.44, 17.02, 20.22, 15.84, 20.00, 22.90, 18.30, 18.90...
$ vs <dbl> 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, ...
$ am <dbl> 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, ...
$ gear <dbl> 4, 4, 4, 3, 3, 3, 3, 4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 4, 4, 4, 3, 3, 3, 3, 3, ...
$ carb <dbl> 4, 4, 1, 1, 2, 1, 4, 2, 2, 4, 4, 3, 3, 3, 4, 4, 4, 1, 2, 1, 1, 2, 2, 4, 2, ...
To get a list of the columns' data type (as said by @Alexandre above):
map(mtcars, class)
gives a list of data types:
$mpg
[1] "numeric"
$cyl
[1] "numeric"
$disp
[1] "numeric"
$hp
[1] "numeric"
To change data type of a column:
library(hablar)
mtcars %>%
convert(chr(mpg, am),
int(carb))
converts columns mpg
and am
to character and the column carb
to integer:
# A tibble: 32 x 11
mpg cyl disp hp drat wt qsec vs am gear carb
<chr> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <chr> <dbl> <int>
1 21 6 160 110 3.9 2.62 16.5 0 1 4 4
2 21 6 160 110 3.9 2.88 17.0 0 1 4 4
3 22.8 4 108 93 3.85 2.32 18.6 1 1 4 1
4 21.4 6 258 110 3.08 3.22 19.4 1 0 3 1
XOR operation can be used to detect number or string. number ^ 0 will always give the number as output and string ^ 0 will give 0 as output.
Example:
1) 2 ^ 0 = 2
2) '2' ^ 0 = 2
3) 'Str' ^ 0 = 0
Look at the these pages on limits.h and float.h, which are included as part of the standard c library.
it is better to use CONCAT function in PostgreSQL for concatenation
eg : select CONCAT(first_name,last_name) from person where pid = 136
if you are using column_a || ' ' || column_b for concatenation for 2 column , if any of the value in column_a or column_b is null query will return null value. which may not be preferred in all cases.. so instead of this
||
use
CONCAT
it will return relevant value if either of them have value
Of course you can use floats or doubles for "critical" things ... Many applications do nothing but crunch numbers using these datatypes.
You might have misunderstood some of the various caveats regarding floating-point numbers, such as the recommendation to never compare for exact equality, and so on.
To summarize the contents of other (already good!) answers, isinstance
caters for inheritance (an instance of a derived class is an instance of a base class, too), while checking for equality of type
does not (it demands identity of types and rejects instances of subtypes, AKA subclasses).
Normally, in Python, you want your code to support inheritance, of course (since inheritance is so handy, it would be bad to stop code using yours from using it!), so isinstance
is less bad than checking identity of type
s because it seamlessly supports inheritance.
It's not that isinstance
is good, mind you—it's just less bad than checking equality of types. The normal, Pythonic, preferred solution is almost invariably "duck typing": try using the argument as if it was of a certain desired type, do it in a try
/except
statement catching all exceptions that could arise if the argument was not in fact of that type (or any other type nicely duck-mimicking it;-), and in the except
clause, try something else (using the argument "as if" it was of some other type).
basestring
is, however, quite a special case—a builtin type that exists only to let you use isinstance
(both str
and unicode
subclass basestring
). Strings are sequences (you could loop over them, index them, slice them, ...), but you generally want to treat them as "scalar" types—it's somewhat incovenient (but a reasonably frequent use case) to treat all kinds of strings (and maybe other scalar types, i.e., ones you can't loop on) one way, all containers (lists, sets, dicts, ...) in another way, and basestring
plus isinstance
helps you do that—the overall structure of this idiom is something like:
if isinstance(x, basestring)
return treatasscalar(x)
try:
return treatasiter(iter(x))
except TypeError:
return treatasscalar(x)
You could say that basestring
is an Abstract Base Class ("ABC")—it offers no concrete functionality to subclasses, but rather exists as a "marker", mainly for use with isinstance
. The concept is obviously a growing one in Python, since PEP 3119, which introduces a generalization of it, was accepted and has been implemented starting with Python 2.6 and 3.0.
The PEP makes it clear that, while ABCs can often substitute for duck typing, there is generally no big pressure to do that (see here). ABCs as implemented in recent Python versions do however offer extra goodies: isinstance
(and issubclass
) can now mean more than just "[an instance of] a derived class" (in particular, any class can be "registered" with an ABC so that it will show as a subclass, and its instances as instances of the ABC); and ABCs can also offer extra convenience to actual subclasses in a very natural way via Template Method design pattern applications (see here and here [[part II]] for more on the TM DP, in general and specifically in Python, independent of ABCs).
For the underlying mechanics of ABC support as offered in Python 2.6, see here; for their 3.1 version, very similar, see here. In both versions, standard library module collections (that's the 3.1 version—for the very similar 2.6 version, see here) offers several useful ABCs.
For the purpose of this answer, the key thing to retain about ABCs (beyond an arguably more natural placement for TM DP functionality, compared to the classic Python alternative of mixin classes such as UserDict.DictMixin) is that they make isinstance
(and issubclass
) much more attractive and pervasive (in Python 2.6 and going forward) than they used to be (in 2.5 and before), and therefore, by contrast, make checking type equality an even worse practice in recent Python versions than it already used to be.
Click Advanced, and then under When calculating this workbook, select the Set precision as displayed check box, and then click OK.
Click OK.
In the worksheet, select the cells that you want to format.
On the Home tab, click the Dialog Box Launcher Button image next to Number.
In the Category box, click Number.
In the Decimal places box, enter the number of decimal places that you want to display.
decimal
.columnName decimal(precision, scale)
. Precision says the total number of digits that can be held in the number, scale says how many of those are after the decimal place, so decimal(3,2)
is a number which can be represented as #.##
; decimal(5,3)
would be ##.###
. decimal
and numeric
are essentially the same thing. However decimal
is ANSI compliant, so always use that unless told otherwise (e.g. by your company's coding standards).Example Scenarios
decimal(5,4)
.decimal(3,2)
.Example:
if object_id('Demo') is null
create table Demo
(
Id bigint not null identity(1,1) constraint pk_Demo primary key
, Name nvarchar(256) not null constraint uk_Demo unique
, SomePercentValue decimal(3,2) constraint chk_Demo_SomePercentValue check (SomePercentValue between 0 and 1)
, SomePrecisionPercentValue decimal(5,2) constraint chk_Demo_SomePrecisionPercentValue check (SomePrecisionPercentValue between 0 and 1)
)
Further Reading:
0 to 1
vs 0 to 100
: C#: Storing percentages, 50 or 0.50?You could do the following:
var inputType = $('#inputid').attr('type');
Additionally, you will see that float
values are rounded.
// e.g: given values 41.0473112,29.0077011 float(11,7) | decimal(11,7) --------------------------- 41.0473099 | 41.0473112 29.0077019 | 29.0077011
You can always use the type(x) == type(y)
trick, where y
is something with known type.
# check if x is a regular string
type(x) == type('')
# check if x is an integer
type(x) == type(1)
# check if x is a NoneType
type(x) == type(None)
Often there are better ways of doing that, particularly with any recent python. But if you only want to remember one thing, you can remember that.
In this case, the better ways would be:
# check if x is a regular string
type(x) == str
# check if x is either a regular string or a unicode string
type(x) in [str, unicode]
# alternatively:
isinstance(x, basestring)
# check if x is an integer
type(x) == int
# check if x is a NoneType
x is None
Note the last case: there is only one instance of NoneType
in python, and that is None
. You'll see NoneType a lot in exceptions (TypeError: 'NoneType' object is unsubscriptable
-- happens to me all the time..) but you'll hardly ever need to refer to it in code.
Finally, as fengshaun points out, type checking in python is not always a good idea. It's more pythonic to just use the value as though it is the type you expect, and catch (or allow to propagate) exceptions that result from it.
In my project I usually use an external function that "filters" data retrieved with mysql_fetch_assoc
.
You can rename fields in your table so that is intuitive to understand which data type is stored.
For example, you can add a special suffix to each numeric field:
if userid
is an INT(11)
you can rename it userid_i
or if it is an UNSIGNED INT(11)
you can rename userid_u
.
At this point, you can write a simple PHP function that receive as input the associative array (retrieved with mysql_fetch_assoc
), and apply casting to the "value" stored with those special "keys".
C does not support this form of type introspection. What you are asking is not possible in C (at least without compiler-specific extensions; it would be possible in C++, however).
In general, with C you're expected to know the types of your variable. Since every function has concrete types for its parameters (except for varargs, I suppose), you don't need to check in the function body. The only remaining case I can see is in a macro body, and, well, C macros aren't really all that powerful.
Further, note that C does not retain any type information into runtime. This means that, even if, hypothetically, there was a type comparison extension, it would only work properly when the types are known at compile time (ie, it wouldn't work to test whether two void *
point to the same type of data).
As for typeof
: First, typeof
is a GCC extension. It is not a standard part of C. It's typically used to write macros that only evaluate their arguments once, eg (from the GCC manual):
#define max(a,b) \
({ typeof (a) _a = (a); \
typeof (b) _b = (b); \
_a > _b ? _a : _b; })
The typeof
keyword lets the macro define a local temporary to save the values of its arguments, allowing them to be evaluated only once.
In short, C does not support overloading; you'll just have to make a func_a(struct a *)
and func_b(struct b *)
, and call the correct one. Alternately, you could make your own introspection system:
struct my_header {
int type;
};
#define TYPE_A 0
#define TYPE_B 1
struct a {
struct my_header header;
/* ... */
};
struct b {
struct my_header header;
/* ... */
};
void func_a(struct a *p);
void func_b(struct b *p);
void func_switch(struct my_header *head);
#define func(p) func_switch( &(p)->header )
void func_switch(struct my_header *head) {
switch (head->type) {
case TYPE_A: func_a((struct a *)head); break;
case TYPE_B: func_b((struct b *)head); break;
default: assert( ("UNREACHABLE", 0) );
}
}
You must, of course, remember to initialize the header properly when creating these objects.
These are the primitive types in Java:
All the other types are reference types: they reference objects.
This is the first part of the Java tutorial about the basics of the language.
As the "GNU C Library Reference Manual" says
off_t
This is a signed integer type used to represent file sizes.
In the GNU C Library, this type is no narrower than int.
If the source is compiled with _FILE_OFFSET_BITS == 64 this
type is transparently replaced by off64_t.
and
off64_t
This type is used similar to off_t. The difference is that
even on 32 bit machines, where the off_t type would have 32 bits,
off64_t has 64 bits and so is able to address files up to 2^63 bytes
in length. When compiling with _FILE_OFFSET_BITS == 64 this type
is available under the name off_t.
Thus if you want reliable way of representing file size between client and server, you can:
off64_t
type and stat64()
function accordingly (as it fills structure stat64
, which contains off64_t
type itself). Type off64_t
guaranties the same size on 32 and 64 bit machines.-D_FILE_OFFSET_BITS == 64
and use usual off_t
and stat()
.off_t
to type int64_t
with fixed size (C99 standard).
Note: (my book 'C in a Nutshell' says that it is C99 standard, but optional in implementation). The newest C11 standard says:7.20.1.1 Exact-width integer types
1 The typedef name intN_t designates a signed integer type with width N ,
no padding bits, and a two’s complement representation. Thus, int8_t
denotes such a signed integer type with a width of exactly 8 bits.
without mentioning.
And about implementation:
7.20 Integer types <stdint.h>
... An implementation shall provide those types described as ‘‘required’’,
but need not provide any of the others (described as ‘‘optional’’).
...
The following types are required:
int_least8_t uint_least8_t
int_least16_t uint_least16_t
int_least32_t uint_least32_t
int_least64_t uint_least64_t
All other types of this form are optional.
Thus, in general, C standard can't guarantee types with fixed sizes. But most compilers (including gcc) support this feature.
Under Visual Studio 2008, it defaults to an __int64
unless you define _USE_32BIT_TIME_T
. You're better off just pretending that you don't know what it's defined as, since it can (and will) change from platform to platform.
I came into the same situation. As a workaround, I just created a view
(If you have privileges) and described it and dropped it later. :)
Just do not do it. Asking for something's type is wrong in itself. Instead use polymorphism. Find or if necessary define by yourself the method that does what you want for any possible type of input and just call it without asking about anything. If you need to work with built-in types or types defined by a third-party library, you can always inherit from them and use your own derivatives instead. Or you can wrap them inside your own class. This is the object-oriented way to resolve such problems.
If you insist on checking exact type and placing some dirty if
s here and there, you can use __class__
property or type
function to do it, but soon you will find yourself updating all these if
s with additional cases every two or three commits. Doing it the OO way prevents that and lets you only define a new class for a new type of input instead.
The first thing you need to decide is whether the data structure needs to be mutable or not. As has been mentioned, lists are mutable, tuples are not. This also means that tuples can be used for dictionary keys, wheres lists cannot.
In my experience, tuples are generally used where order and position is meaningful and consistant. For example, in creating a data structure for a choose your own adventure game, I chose to use tuples instead of lists because the position in the tuple was meaningful. Here is one example from that data structure:
pages = {'foyer': {'text' : "some text",
'choices' : [('open the door', 'rainbow'),
('go left into the kitchen', 'bottomless pit'),
('stay put','foyer2')]},}
The first position in the tuple is the choice displayed to the user when they play the game and the second position is the key of the page that choice goes to and this is consistent for all pages.
Tuples are also more memory efficient than lists, though I'm not sure when that benefit becomes apparent.
Also check out the chapters on lists and tuples in Think Python.
At some point, you're trying to convert an nvarchar
column to a varchar
column (or vice-versa).
Moreover, why is everything (supposedly) nvarchar(max)
? That's a code smell if I ever saw one. Are you aware of how SQL Server stores those columns? They use pointers to where the column is stored from the actual rows, since they don't fit within the 8k pages.
Dim tblReady1 As DataTable = tblReady.Clone()
'' convert all the columns type to String
For Each col As DataColumn In tblReady1.Columns
col.DataType = GetType(String)
Next
tblReady1.Load(tblReady.CreateDataReader)
Comparing an object with a class using instanceOf
or ... is already answered.
If you have two objects and you want to compare their types with each other, you can use:
if (obj1.getClass() == obj2.getClass()) {
// Both have the same type
}
Simple casting:
int a = 99;
char c = (char) a;
Is there any reason this is not working for you?
Another difference between bool and BOOL is that they do not convert exactly to the same kind of objects, when you do key-value observing, or when you use methods like -[NSObject valueForKey:].
As everybody has said here, BOOL is char. As such, it is converted to an NSNumber holding a char. This object is indistinguishable from an NSNumber created from a regular char like 'A' or '\0'. You have totally lost the information that you originally had a BOOL.
However, bool is converted to an CFBoolean, which behaves the same as NSNumber, but which retains the boolean origin of the object.
I do not think that this is an argument in a BOOL vs. bool debate, but this may bite you one day.
Generally speaking, you should go with BOOL, since this is the type used everywhere in the Cocoa/iOS APIs (designed before C99 and its native bool type).
You have some variables that are different types in Java language like that:
message of type string
timestamp of type time
count of type integer
version of type integer
If you use a HashMap like:
HashMap<String,Object> yourHash = new HashMap<String,Object>();
yourHash.put("message","message");
yourHash.put("timestamp",timestamp);
yourHash.put("count ",count);
yourHash.put("version ",version);
If you want to use the yourHash:
for(String key : yourHash.keySet()){
String message = (String) yourHash.get(key);
Datetime timestamp= (Datetime) yourHash.get(key);
int timestamp= (int) yourHash.get(key);
}
Well, personally I do not use numeric datatype to store phone numbers or related info.
How do you store a number say 001234567? It'll end up as 1234567, losing the leading zeros.
Of course you can always left-pad it up, but that's provided you know exactly how many digits the number should be.
This doesn't answer your entire post,
Just my 2 cents
In Rails 3.2.18, :decimal turns into :integer when using SQLServer, but it works fine in SQLite. Switching to :float solved this issue for us.
The lesson learned is "always use homogeneous development and deployment databases!"
It means "a python object", i.e. not one of the builtin scalar types supported by numpy.
np.array([object()]).dtype
=> dtype('O')
Quite a few utility libraries such as YourJS offer functions for determining if something is an array or if something is an integer or a lot of other types as well. YourJS defines isInt by checking if the value is a number and then if it is divisible by 1:
function isInt(x) {
return typeOf(x, 'Number') && x % 1 == 0;
}
The above snippet was taken from this YourJS snippet and thusly only works because typeOf
is defined by the library. You can download a minimalistic version of YourJS which mainly only has type checking functions such as typeOf()
, isInt()
and isArray()
: http://yourjs.com/snippets/build/34,2
Since you're going to be dealing with data of a variable length (names, email addresses), then you'd be wanting to use VARCHAR. The amount of space taken up by a VARCHAR field is [field length]
+ 1 bytes, up to max length 255, so I wouldn't worry too much about trying to find a perfect size. Take a look at what you'd imagine might be the longest length might be, then double it and set that as your VARCHAR limit. That said...:
I generally set email fields to be VARCHAR(100) - i haven't come up with a problem from that yet. Names I set to VARCHAR(50).
As the others have said, phone numbers and zip/postal codes are not actually numeric values, they're strings containing the digits 0-9 (and sometimes more!), and therefore you should treat them as a string. VARCHAR(20) should be well sufficient.
Note that if you were to store phone numbers as integers, many systems will assume that a number starting with 0 is an octal (base 8) number! Therefore, the perfectly valid phone number "0731602412" would get put into your database as the decimal number "124192010"!!
you can just use JSON.stringify
to test your Object, like this:
var test = {}_x000D_
if(JSON.stringify(test)[0] === '{') {_x000D_
console.log('this is a Object')_x000D_
}
_x000D_
If multiple types are possible, the method itself does not know the type to cast, but the caller does, you might use something like this:
void TheObliviousHelperMethod<T>(object obj) {
(T)obj.ThatClassMethodYouWantedToInvoke();
}
// Meanwhile, where the method is called:
TheObliviousHelperMethod<ActualType>(obj);
Restrictions on the type could be added using the where
keyword after the parentheses.
You can do this, just wrap it in typeof()
foo.GetColumnValues(typeof(int))
public void GetColumnValues(Type type)
{
//logic
}
After not finding anything to get around "Object must implement IConvertible" exception when using Zyphrax's answer (except for implementing the interface).. I tried something a little bit unconventional and worked for my situation.
Using the Newtonsoft.Json nuget package...
var castedObject = JsonConvert.DeserializeObject(JsonConvert.SerializeObject(myObject), myType);
practical usage:
public string someFunctionThatMayBeCalledWithNullAndReturnsString(int? value)
{
if (value == null)
{
return "bad value";
}
return someFunctionThatHandlesIntAndReturnsString(value);
}
There are already many good answers to the part "what is uintptr_t data type". I will try to address the "what it can be used for?" part in this post.
Primarily for bitwise operations on pointers. Remember that in C++ one cannot perform bitwise operations on pointers. For reasons see Why can't you do bitwise operations on pointer in C, and is there a way around this?
Thus in order to do bitwise operations on pointers one would need to cast pointers to type unitpr_t and then perform bitwise operations.
Here is an example of a function that I just wrote to do bitwise exclusive or of 2 pointers to store in a XOR linked list so that we can traverse in both directions like a doubly linked list but without the penalty of storing 2 pointers in each node.
template <typename T>
T* xor_ptrs(T* t1, T* t2)
{
return reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(t1)^reinterpret_cast<uintptr_t>(t2));
}
Use Math.ceil()
and cast the result to int:
Example:
(int) Math.ceil((double)divident / divisor);
If we have to answer the question: String is a reference type and it behaves as a reference. We pass a parameter that holds a reference to, not the actual string. The problem is in the function:
public static void TestI(string test)
{
test = "after passing";
}
The parameter test
holds a reference to the string but it is a copy. We have two variables pointing to the string. And because any operations with strings actually create a new object, we make our local copy to point to the new string. But the original test
variable is not changed.
The suggested solutions to put ref
in the function declaration and in the invocation work because we will not pass the value of the test
variable but will pass just a reference to it. Thus any changes inside the function will reflect the original variable.
I want to repeat at the end: String is a reference type but since its immutable the line test = "after passing";
actually creates a new object and our copy of the variable test
is changed to point to the new string.
It has nothing to do with append
. tuple(3, 4)
all by itself raises that error.
The reason is that, as the error message says, tuple
expects an iterable argument. You can make a tuple of the contents of a single object by passing that single object to tuple. You can't make a tuple of two things by passing them as separate arguments.
Just do (3, 4)
to make a tuple, as in your first example. There's no reason not to use that simple syntax for writing a tuple.
The concept of POD and the type trait std::is_pod
will be deprecated in C++20. See this question for further information.
Starting pandas 1.0.0, we have pandas.DataFrame.convert_dtypes
. You can even control what types to convert!
In [40]: df = pd.DataFrame(
...: {
...: "a": pd.Series([1, 2, 3], dtype=np.dtype("int32")),
...: "b": pd.Series(["x", "y", "z"], dtype=np.dtype("O")),
...: "c": pd.Series([True, False, np.nan], dtype=np.dtype("O")),
...: "d": pd.Series(["h", "i", np.nan], dtype=np.dtype("O")),
...: "e": pd.Series([10, np.nan, 20], dtype=np.dtype("float")),
...: "f": pd.Series([np.nan, 100.5, 200], dtype=np.dtype("float")),
...: }
...: )
In [41]: dff = df.copy()
In [42]: df
Out[42]:
a b c d e f
0 1 x True h 10.0 NaN
1 2 y False i NaN 100.5
2 3 z NaN NaN 20.0 200.0
In [43]: df.dtypes
Out[43]:
a int32
b object
c object
d object
e float64
f float64
dtype: object
In [44]: df = df.convert_dtypes()
In [45]: df.dtypes
Out[45]:
a Int32
b string
c boolean
d string
e Int64
f float64
dtype: object
In [46]: dff = dff.convert_dtypes(convert_boolean = False)
In [47]: dff.dtypes
Out[47]:
a Int32
b string
c object
d string
e Int64
f float64
dtype: object
A simplest fix would be:
x = input("Give starting number: ")
y = input("Give ending number: ")
x = int(x) # parse string into an integer
y = int(y) # parse string into an integer
for i in range(x,y):
print(i)
input
returns you a string (raw_input
in Python 2). int
tries to parse it into an integer. This code will throw an exception if the string doesn't contain a valid integer string, so you'd probably want to refine it a bit using try
/except
statements.
Its pretty simple. Assume that your classname is Car
and the namespace is Vehicles
, then pass the parameter as Vehicles.Car
which returns object of type Car
. Like this you can create any instance of any class dynamically.
public object GetInstance(string strNamesapace)
{
Type t = Type.GetType(strNamesapace);
return Activator.CreateInstance(t);
}
If your Fully Qualified Name(ie, Vehicles.Car
in this case) is in another assembly, the Type.GetType
will be null. In such cases, you have loop through all assemblies and find the Type
. For that you can use the below code
public object GetInstance(string strFullyQualifiedName)
{
Type type = Type.GetType(strFullyQualifiedName);
if (type != null)
return Activator.CreateInstance(type);
foreach (var asm in AppDomain.CurrentDomain.GetAssemblies())
{
type = asm.GetType(strFullyQualifiedName);
if (type != null)
return Activator.CreateInstance(type);
}
return null;
}
And you can get the instance by calling the above method.
object objClassInstance = GetInstance("Vehicles.Car");
In C and C++
unsigned = unsigned int (Integer type)
signed = signed int (Integer type)
An unsigned integer containing n bits can have a value between 0 and (2^n-1) , which is 2^n different values.
An unsigned integer is either positive or zero.
Signed integers are stored in a computer using 2's complement.
Numeric defines the TOTAL number of digits, and then the number after the decimal.
A numeric(3,2) can only hold up to 9.99.
Old style classes are still marginally faster for attribute lookup. This is not usually important, but it may be useful in performance-sensitive Python 2.x code:
In [3]: class A: ...: def __init__(self): ...: self.a = 'hi there' ...: In [4]: class B(object): ...: def __init__(self): ...: self.a = 'hi there' ...: In [6]: aobj = A() In [7]: bobj = B() In [8]: %timeit aobj.a 10000000 loops, best of 3: 78.7 ns per loop In [10]: %timeit bobj.a 10000000 loops, best of 3: 86.9 ns per loop
For simple case (one currency) it'is enough int
/long
.
Keep money in cents (...) or hundredth / thousandth of cents (any precision you need with fixed divider)
For myself, I would assume unsigned int is platform specific. Integer could be 8 bits, 16 bits, 32 bits or even 64 bits.
DWORD in the other hand, specifies its own size, which is Double Word. Word are 16 bits so DWORD will be known as 32 bit across all platform
Try:
num3 = 100000000000LL;
And BTW, in C++ this is a compiler extension, the standard does not define long long, thats part of C99.
For those future visitors who may be interested in knowing about those memory segments, I am writing important points about 5 memory segments in C:
Some heads up:
5 Memory Segments in C:
printf("Hello, world")
then string "Hello, world" gets created in the code/text segment. You can verify this using size
command in Linux OS.The data segment is divided in the below two parts and typically lies below the heap area or in some implementations above the stack, but the data segment never lies between the heap and stack area.
int globalVar;
or static local variable static int localStatic;
will be stored in the uninitialized data segment.0
or NULL
then still it would go to uninitialized data segment or bss.int globalVar = 1;
or static local variable static int localStatic = 1;
will be stored in initialized data segment.malloc
, calloc
, or realloc
methods.int* prt = malloc(sizeof(int) * 2)
then eight bytes will be allocated in heap and memory address of that location will be returned and stored in ptr
variable. The ptr
variable will be on either the stack or data segment depending on the way it is declared/used.I had a similar issue recently while trying to link with the pre-built binaries of hdf5 version 1.10.5 on Ubuntu 16.04. None of the solutions suggested here worked for me, and I was using g++ version 9.1. I found that the best solution is to build the hdf5 library from source. Do not use the pre-built binaries since these were built using gcc 4.9! Instead, download the source code archives from the hdf website for your particular distribution and build the library. It is very easy.
You will also need the compression libraries zlib and szip from here and here, respectively, if you do not already have them on your system.
size_t
is an unsigned type that can hold maximum integer value for your architecture, so it is protected from integer overflows due to sign (signed int 0x7FFFFFFF
incremented by 1 will give you -1) or short size (unsigned short int 0xFFFF incremented by 1 will give you 0).
It is mainly used in array indexing/loops/address arithmetic and so on. Functions like memset()
and alike accept size_t
only, because theoretically you may have a block of memory of size 2^32-1
(on 32bit platform).
For such simple loops don't bother and use just int.
Let me list a use case below. Hope it helps. Here I'm trying to find the Table Owner of the Table 'Stud_dtls' from the DB 'Students'. As Mikael mentioned, sysname could be used when there is a need for creating some dynamic sql which needs variables holding table names, column names and server names. Just thought of providing a simple example to supplement his point.
USE Students
DECLARE @TABLE_NAME sysname
SELECT @TABLE_NAME = 'Stud_dtls'
SELECT TABLE_SCHEMA
FROM INFORMATION_SCHEMA.Tables
WHERE TABLE_NAME = @TABLE_NAME
4294967295 is the answer, because int(11) shows maximum of 11 digits IMO
As Paul stated, it's because 'a'
is an int
in C but a char
in C++.
I cover that specific difference between C and C++ in something I wrote a few years ago, at: http://david.tribble.com/text/cdiffs.htm
I just found something in the TypeScript language specification, it's fairly easy. I was pretty close.
the syntax is the following:
public myCallback: (name: type) => returntype;
In my example, it would be
class CallbackTest
{
public myCallback: () => void;
public doWork(): void
{
//doing some work...
this.myCallback(); //calling callback
}
}
For more complex type validations I like typeguard's approach of validating based on python type hint annotations:
from typeguard import check_type
from typing import List
try:
check_type('mylist', [1, 2], List[int])
except TypeError as e:
print(e)
You can perform very complex validations in very clean and readable fashion.
check_type('foo', [1, 3.14], List[Union[int, float]])
# vs
isinstance(foo, list) and all(isinstance(a, (int, float)) for a in foo)
When you select a column with type ZEROFILL
it pads the displayed value of the field with zeros up to the display width specified in the column definition. Values longer than the display width are not truncated. Note that usage of ZEROFILL
also implies UNSIGNED
.
Using ZEROFILL
and a display width has no effect on how the data is stored. It affects only how it is displayed.
Here is some example SQL that demonstrates the use of ZEROFILL
:
CREATE TABLE yourtable (x INT(8) ZEROFILL NOT NULL, y INT(8) NOT NULL);
INSERT INTO yourtable (x,y) VALUES
(1, 1),
(12, 12),
(123, 123),
(123456789, 123456789);
SELECT x, y FROM yourtable;
Result:
x y
00000001 1
00000012 12
00000123 123
123456789 123456789
Use Number
from the numbers
module to test isinstance(n, Number)
(available since 2.6).
isinstance(n, numbers.Number)
Here it is in action with various kinds of numbers and one non-number:
>>> from numbers import Number
... from decimal import Decimal
... from fractions import Fraction
... for n in [2, 2.0, Decimal('2.0'), complex(2,0), Fraction(2,1), '2']:
... print '%15s %s' % (n.__repr__(), isinstance(n, Number))
2 True
2.0 True
Decimal('2.0') True
(2+0j) True
Fraction(2, 1) True
'2' False
This is, of course, contrary to duck typing. If you are more concerned about how an object acts rather than what it is, perform your operations as if you have a number and use exceptions to tell you otherwise.
git pull
wants you to either remove or save your current work so that the merge it triggers doesn't cause conflicts with your uncommitted work. Note that you should only need to remove/save untracked files if the changes you're pulling create files in the same locations as your local uncommitted files.
git checkout -f
git clean -fd
git stash
git stash -u
git pull
:git stash pop
What I do with my TestNG, (sorry, JUnit doesn't support this) test cases is I can assign a group to the test I want to run
@Test(groups="broken")
And then simply run 'mvn -Dgroups=broken'.
you should use this
del record[-1]
The problem with
record = record[:-1]
Is that it makes a copy of the list every time you remove an item, so isn't very efficient
The source code for BufferedReader shows that the underlying is closed when you close the BufferedReader.
This is the shell function I use to get my SSH key finger print for creating DigitalOcean droplets:
fingerprint() {
pubkeypath="$1"
ssh-keygen -E md5 -lf "$pubkeypath" | awk '{ print $2 }' | cut -c 5-
}
Put it in your ~/.bashrc
, source it, and then you can get the finger print as so:
$ fingerprint ~/.ssh/id_rsa.pub
d2:47:0a:87:30:a0:c0:df:6b:42:19:55:b4:f3:09:b9
What is the best way to implement Singleton in Java, in a multithreaded environment?
Refer to this post for best way to implement Singleton.
What is an efficient way to implement a singleton pattern in Java?
What happens when multiple threads try to access getInstance() method at the same time?
It depends on the way you have implemented the method.If you use double locking without volatile variable, you may get partially constructed Singleton object.
Refer to this question for more details:
Why is volatile used in this example of double checked locking
Can we make singleton's getInstance() synchronized?
Is synchronization really needed, when using Singleton classes?
Not required if you implement the Singleton in below ways
Refer to this question fore more details
Println(Object)
uses String.valueOf()
public static String valueOf(Object obj) {
return (obj == null) ? "null" : obj.toString();
}
Print(String)
does null check.
public void print(String s) {
if (s == null) {
s = "null";
}
write(s);
}
Modifying, or more correctly, adding additional HTTP headers is a great code debugging tool if nothing else.
When a URL request returns a redirect or an image there is no html "page" to temporarily write the results of debug code to - at least not one that is visible in a browser.
One approach is to write the data to a local log file and view that file later. Another is to temporarily add HTTP headers reflecting the data and variables being debugged.
I regularly add extra HTTP headers like X-fubar-somevar: or X-testing-someresult: to test things out - and have found a lot of bugs that would have otherwise been very difficult to trace.
T
and TRUE
are True, F
and FALSE
are False. T
and F
can be redefined, however, so you should only rely upon TRUE
and FALSE
. If you compare 0 to FALSE and 1 to TRUE, you will find that they are equal as well, so you might consider them to be True and False as well.
It may be time consuming to get all the application Ids from YARN and kill them one by one. You can use a Bash for loop to accomplish this repetitive task quickly and more efficiently as shown below:
Kill all applications on YARN which are in ACCEPTED state:
for x in $(yarn application -list -appStates ACCEPTED | awk 'NR > 2 { print $1 }'); do yarn application -kill $x; done
Kill all applications on YARN which are in RUNNING state:
for x in $(yarn application -list -appStates RUNNING | awk 'NR > 2 { print $1 }'); do yarn application -kill $x; done
As I understand, you want the average value for each id at each pass. The solution is
SELECT id, pass, avg(value) FROM data_r1
GROUP BY id, pass;
Using Integer.toHexString(...)
is a good answer. But personally prefer to use String.format(...)
.
Try this sample as a test.
byte[] values = new byte[64];
Arrays.fill(values, (byte)8); //Fills array with 8 just for test
String valuesStr = "";
for(int i = 0; i < values.length; i++)
valuesStr += String.format("0x%02x", values[i] & 0xff) + " ";
valuesStr.trim();
I totally missed the export button at the bottom of each visualization. As for read only access...Shield from Elasticsearch might be worth exploring.
You could use a colormap such as HSV to generate a set of colors. For example:
cc=hsv(12);
figure;
hold on;
for i=1:12
plot([0 1],[0 i],'color',cc(i,:));
end
MATLAB has 13 different named colormaps ('doc colormap' lists them all).
Another option for plotting lines in different colors is to use the LineStyleOrder property; see Defining the Color of Lines for Plotting in the MATLAB documentation for more information.
If you would like to purposely link your project A in Release against another project B in Debug, say to keep the overall performance benefits of your application while debugging, then you will likely hit this error. You can fix this by temporarily modifying the preprocessor flags of project B to disable iterator debugging (and make it match project A):
In Project B's "Debug" properties, Configuration Properties -> C/C++ -> Preprocessor, add the following to Preprocessor Definitions:
_HAS_ITERATOR_DEBUGGING=0;_ITERATOR_DEBUG_LEVEL=0;
Rebuild project B in Debug, then build project A in Release and it should link correctly.
I had been into the similar situation. After doing research and testing, here is my findings:
With Spring Boot, the recommended way to enable global CORS is to declare within Spring MVC and combined with fine-grained @CrossOrigin
configuration as:
@Configuration
public class CorsConfig {
@Bean
public WebMvcConfigurer corsConfigurer() {
return new WebMvcConfigurerAdapter() {
@Override
public void addCorsMappings(CorsRegistry registry) {
registry.addMapping("/**").allowedMethods("GET", "POST", "PUT", "DELETE").allowedOrigins("*")
.allowedHeaders("*");
}
};
}
}
Now, since you are using Spring Security, you have to enable CORS at Spring Security level as well to allow it to leverage the configuration defined at Spring MVC level as:
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
@Override
protected void configure(HttpSecurity http) throws Exception {
http.cors().and()...
}
}
Here is very excellent tutorial explaining CORS support in Spring MVC framework.
I wouldn't set the ngmodel via an attribute, you can specify it right in the template:
template: '<div class="some"><label>{{label}}</label><input data-ng-model="ngModel"></div>',
As explained in the openpub documentations,
pthread_exit()
will exit the thread that calls it.
In your case since the main calls it, main thread will terminate whereas your spawned threads will continue to execute. This is mostly used in cases where the main thread is only required to spawn threads and leave the threads to do their job
pthread_join
will suspend execution of the thread that has called it unless the target thread terminates
This is useful in cases when you want to wait for thread/s to terminate before further processing in main thread.
First, you need to create your branch locally
git checkout -b your_branch
After that, you can work locally in your branch, when you are ready to share the branch, push it. The next command push the branch to the remote repository origin and tracks it
git push -u origin your_branch
Your Teammates/colleagues can push to your branch by doing commits and then push explicitly
... work ...
git commit
... work ...
git commit
git push origin HEAD:refs/heads/your_branch
$('.button1').click(function() {
window.location = "www.example.com/index.php?id=" + this.id;
});
First of all using window.location
is better as according to specification document.location
value was read-only and might cause you headaches in older/different browsers. Check notes @MDC DOM document.location page
And for the second - using attr
jQuery method to get id is a bad practice - you should use direct native DOM accessor this.id
as the value assigned to this
is normal DOM element.
Top answer doesn't work in mysql 5.6+. Use this instead:
[mysqld]
general_log = on
general_log_file=/usr/log/general.log
in your my.cnf / my.ini file
Ubuntu/Debian: /etc/mysql/my.cnf
Windows: c:\ProgramData\MySQL\MySQL Server 5.x
wamp: c:\wamp\bin\mysql\mysqlx.y.z\my.ini
xampp: c:\xampp\mysql\bin\my.ini.
You check if it's null
in C# like this:
if(MyObject != null) {
//do something
}
If you want to check against default (tough to understand the question on the info given) check:
if(MyObject != default(MyObject)) {
//do something
}
The Path is the only thing you really have to worry about if you are really new to Java. You need to drag your image into the main project file, and it will show up at the very bottom of the list.
Then the file path is pretty straight forward. This code goes into the constructor for the class.
img = Toolkit.getDefaultToolkit().createImage("/home/ben/workspace/CS2/Background.jpg");
CS2 is the name of my project, and everything before that is leading to the workspace.
You can use JavaScripts Fetch API (available in your browser) to make network requests.
If using node, you will need to install the node-fetch package.
const url = "https://api.wit.ai/message?v=20140826&q=";
const options = {
headers: {
Authorization: "Bearer 6Q************"
}
};
fetch(url, options)
.then( res => res.json() )
.then( data => console.log(data) );
The command to just stream it to a new container (mp4) needed by some applications like Adobe Premiere Pro without encoding (fast) is:
ffmpeg -i input.mov -qscale 0 output.mp4
Alternative as mentioned in the comments, which re-encodes with best quaility (-qscale 0
):
ffmpeg -i input.mov -q:v 0 output.mp4
I want to just refresh the div, without refreshing the page ... Is this possible?
Yes, though it isn't going to be obvious that it does anything unless you change the contents of the div.
If you just want the graphical fade-in effect, simply remove the .html(data)
call:
$("#panel").hide().fadeIn('fast');
Here is a demo you can mess around with: http://jsfiddle.net/ZPYUS/
It changes the contents of the div without making an ajax call to the server, and without refreshing the page. The content is hard coded, though. You can't do anything about that fact without contacting the server somehow: ajax, some sort of sub-page request, or some sort of page refresh.
html:
<div id="panel">test data</div>
<input id="changePanel" value="Change Panel" type="button">?
javascript:
$("#changePanel").click(function() {
var data = "foobar";
$("#panel").hide().html(data).fadeIn('fast');
});?
css:
div {
padding: 1em;
background-color: #00c000;
}
input {
padding: .25em 1em;
}?
For boot2docker, we can set it on /var/lib/boot2docker/profile
, for instance:
ulimit -n 2018
Be warned not to set this limit too high as it will slow down apt-get! See bug #1332440. I had it with debian jessie.
Some nice intuition that might help, using any Linux(ish) console.
Create two files:
$ touch foo; touch bar
Enter some Data into them:
$ echo "Cat" > foo
$ echo "Dog" > bar
(Actually, I could have used echo in the first place, as it creates the files if they don't exist... but never mind that.)
And as expected:
$cat foo; cat bar
Cat
Dog
Let's create hard and soft links:
$ ln foo foo-hard
$ ln -s bar bar-soft
Let's see what just happened:
$ ls -l
foo
foo-hard
bar
bar-soft -> bar
Changing the name of foo does not matter:
$ mv foo foo-new
$ cat foo-hard
Cat
foo-hard points to the inode, the contents, of the file - that wasn't changed.
$ mv bar bar-new
$ ls bar-soft
bar-soft
$ cat bar-soft
cat: bar-soft: No such file or directory
The contents of the file could not be found because the soft link points to the name, that was changed, and not to the contents.
Likewise, If foo
is deleted, foo-hard
still holds the contents; if bar
is deleted, bar-soft
is just a link to a non-existing file.
The strncpy()
function was designed with a very particular problem in mind: manipulating strings stored in the manner of original UNIX directory entries. These used a fixed sized array, and a nul-terminator was only used if the filename was shorter than the array.
That's what's behind the two oddities of strncpy()
:
For a "safer strcpy()
", you are better off using strncat()
like so:
if (dest_size > 0)
{
dest[0] = '\0';
strncat(dest, source, dest_size - 1);
}
That will always nul-terminate the result, and won't copy more than necessary.
Like it's written up there, you forget to type #include <sstream>
#include <sstream>
using namespace std;
QString Stats_Manager::convertInt(int num)
{
stringstream ss;
ss << num;
return ss.str();
}
You can also use some other ways to convert int
to string
, like
char numstr[21]; // enough to hold all numbers up to 64-bits
sprintf(numstr, "%d", age);
result = name + numstr;
check this!
thead {
position: fixed;
height: 10px; /* This is whatever height you want */
}
tbody {
position: fixed;
margin-top: 10px; /* This has to match the height of thead */
height: 300px; /* This is whatever height you want */
}
I had an issue with XCode 10.2 specifying the correct iOS simulator version number, so used:
react-native run-ios --simulator='iPhone X (com.apple.CoreSimulator.SimRuntime.iOS-12-1)'
Two steps worked for me : - going Macintosh HD > Applications > Python3.7 folder - click on "Install Certificates.command"
Recursively add subfolders,
for i in `find . -name "*.java" -type f`; do
echo "$i"
done
If just want to user pure Linq, you can use groupby:
List<obj> distinct =
objs.GroupBy(car => car.typeID).Select(g => g.First()).ToList();
If you want a method to be used all across the app, similar to what MoreLinq does:
public static IEnumerable<TSource> DistinctBy<TSource, TKey>
(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)
{
HashSet<TKey> seenKeys = new HashSet<TKey>();
foreach (TSource element in source)
{
if (!seenKeys.Contains(keySelector(element)))
{
seenKeys.Add(keySelector(element));
yield return element;
}
}
}
Using this method to find the distinct values using just the Id property, you could use:
var query = objs.DistinctBy(p => p.TypeId);
you can use multiple properties:
var query = objs.DistinctBy(p => new { p.TypeId, p.Name });
/*reading string which contains spaces*/
#include<stdio.h>
int main()
{
char *c,*p;
scanf("%[^\n]s",c);
p=c; /*since after reading then pointer points to another
location iam using a second pointer to store the base
address*/
printf("%s",p);
return 0;
}
I think the OP is asking how to swap a VIEW without changing viewCONTROLLERs. Am I misunderstanding his question?
In pseudocode, he wants to do:
let myController = instantiate(someParentController)
let view1 = Bundle.main.loadNib(....) as... blah
myController.setThisViewTo( view1 )
let view2 = Bundle.main.loadNib(....) as... blah
myController.setThisViewTo( view2 )
Am I getting his question wrong?
This was the top result when googling "cannot open source file" so I figured I would share what my issue was since I had already included the correct path.
I'm not sure about other IDEs or compilers, but least for Visual Studio, make sure there isn't a space in your list of include directories. I had put a space between the ;
of the last entry and the beginning of my new entry which then caused Visual Studio to disregard my inclusion.
Their names should help you:
android:gravity
sets the gravity of the contents (i.e. its subviews) of the View
it's used on. android:layout_gravity
sets the gravity of the View
or Layout
relative to its parent. And an example is here.
A monad is an array of functions
(Pst: an array of functions is just a computation).
Actually, instead of a true array (one function in one cell array) you have those functions chained by another function >>=. The >>= allows to adapt the results from function i to feed function i+1, perform calculations between them or, even, not to call function i+1.
The types used here are "types with context". This is, a value with a "tag". The functions being chained must take a "naked value" and return a tagged result. One of the duties of >>= is to extract a naked value out of its context. There is also the function "return", that takes a naked value and puts it with a tag.
An example with Maybe. Let's use it to store a simple integer on which make calculations.
-- a * b
multiply :: Int -> Int -> Maybe Int
multiply a b = return (a*b)
-- divideBy 5 100 = 100 / 5
divideBy :: Int -> Int -> Maybe Int
divideBy 0 _ = Nothing -- dividing by 0 gives NOTHING
divideBy denom num = return (quot num denom) -- quotient of num / denom
-- tagged value
val1 = Just 160
-- array of functions feeded with val1
array1 = val1 >>= divideBy 2 >>= multiply 3 >>= divideBy 4 >>= multiply 3
-- array of funcionts created with the do notation
-- equals array1 but for the feeded val1
array2 :: Int -> Maybe Int
array2 n = do
v <- divideBy 2 n
v <- multiply 3 v
v <- divideBy 4 v
v <- multiply 3 v
return v
-- array of functions,
-- the first >>= performs 160 / 0, returning Nothing
-- the second >>= has to perform Nothing >>= multiply 3 ....
-- and simply returns Nothing without calling multiply 3 ....
array3 = val1 >>= divideBy 0 >>= multiply 3 >>= divideBy 4 >>= multiply 3
main = do
print array1
print (array2 160)
print array3
Just to show that monads are array of functions with helper operations, consider the equivalent to the above example, just using a real array of functions
type MyMonad = [Int -> Maybe Int] -- my monad as a real array of functions
myArray1 = [divideBy 2, multiply 3, divideBy 4, multiply 3]
-- function for the machinery of executing each function i with the result provided by function i-1
runMyMonad :: Maybe Int -> MyMonad -> Maybe Int
runMyMonad val [] = val
runMyMonad Nothing _ = Nothing
runMyMonad (Just val) (f:fs) = runMyMonad (f val) fs
And it would be used like this:
print (runMyMonad (Just 160) myArray1)
Depending on your project, disabling exceptions for guzzle might be necessary. Sometimes coding rules disallow exceptions for flow control. You can disable exceptions for Guzzle 3 like this:
$client = new \Guzzle\Http\Client($httpBase, array(
'request.options' => array(
'exceptions' => false,
)
));
This does not disable curl exceptions for something like timeouts, but now you can get every status code easily:
$request = $client->get($uri);
$response = $request->send();
$statuscode = $response->getStatusCode();
To check, if you got a valid code, you can use something like this:
if ($statuscode > 300) {
// Do some error handling
}
... or better handle all expected codes:
if (200 === $statuscode) {
// Do something
}
elseif (304 === $statuscode) {
// Nothing to do
}
elseif (404 === $statuscode) {
// Clean up DB or something like this
}
else {
throw new MyException("Invalid response from api...");
}
For Guzzle 5.3
$client = new \GuzzleHttp\Client(['defaults' => [ 'exceptions' => false ]] );
Thanks to @mika
For Guzzle 6
$client = new \GuzzleHttp\Client(['http_errors' => false]);
I would like to give example rather than the formal definition.
var originalObject = {
a : 1,
b : 2,
c : 3,
};
This code shows a shallow copy:
var copyObject1 = originalObject;
console.log(copyObject1.a); // it will print 1
console.log(originalObject.a); // it will also print 1
copyObject1.a = 4;
console.log(copyObject1.a); //now it will print 4
console.log(originalObject.a); // now it will also print 4
var copyObject2 = Object.assign({}, originalObject);
console.log(copyObject2.a); // it will print 1
console.log(originalObject.a); // it will also print 1
copyObject2.a = 4;
console.log(copyObject2.a); // now it will print 4
console.log(originalObject.a); // now it will print 1
This code shows a deep copy:
var copyObject2 = Object.assign({}, originalObject);
console.log(copyObject2.a); // it will print 1
console.log(originalObject.a); // it will also print 1
copyObject2.a = 4;
console.log(copyObject2.a); // now it will print 4
console.log(originalObject.a); // !! now it will print 1 !!
No need to care of whether before/after this digit having other type of words
To just match the pattern of 5 digits number anywhere in the string, no matter it is separated by space or not, use this regular expression (?<!\d)\d{5}(?!\d)
.
Sample JavaScript codes:
var regexp = new RegExp(/(?<!\d)\d{5}(?!\d)/g);
var matches = yourstring.match(regexp);
if (matches && matches.length > 0) {
for (var i = 0, len = matches.length; i < len; i++) {
// ... ydo something with matches[i] ...
}
}
Here's some quick results.
abc12345xyz (?)
12345abcd (?)
abcd12345 (?)
0000aaaa2 (?)
a1234a5 (?)
12345 (?)
<space>
12345<space>
12345 (??)
Assuming you want to get the value if the key does exist, use Dictionary<TKey, TValue>.TryGetValue
:
int value;
if (dictionary.TryGetValue(key, out value))
{
// Key was in dictionary; "value" contains corresponding value
}
else
{
// Key wasn't in dictionary; "value" is now 0
}
(Using ContainsKey
and then the the indexer makes it look the key up twice, which is pretty pointless.)
Note that even if you were using reference types, checking for null wouldn't work - the indexer for Dictionary<,>
will throw an exception if you request a missing key, rather than returning null. (This is a big difference between Dictionary<,>
and Hashtable
.)
you can run something like this (paste the code bellow in a .bat, or if you want it to run interractively replace the %%
by %
:
for %%i in (c:\directory\*.xls) do ssconvert %%i %%i.xlsx
If you can run powershell it will be :
Get-ChildItem -Path c:\directory -filter *.xls | foreach {ssconvert $($_.FullName) $($_.baseName).xlsx }
Clear your cookies
When using PHPMyAdmin configured with multiple databases, one having the phpmyadmin table and another not having it; phpmyadmin will store preferences for the database with the table in your cookies then try to load them with the database that doesn't have the table.
To test, try using an incognito window.
You can run the cd
and the executable in a subshell by enclosing the command line in a pair of parentheses:
(cd SOME_PATH && exec_some_command)
Demo:
$ pwd
/home/abhijit
$ (cd /tmp && pwd) # directory changed in the subshell
/tmp
$ pwd # parent shell's pwd is still the same
/home/abhijit
Here are some branch naming conventions that I use and the reasons for them
Branch naming conventions
Group tokens
Use "grouping" tokens in front of your branch names.
group1/foo
group2/foo
group1/bar
group2/bar
group3/bar
group1/baz
The groups can be named whatever you like to match your workflow. I like to use short nouns for mine. Read on for more clarity.
Short well-defined tokens
Choose short tokens so they do not add too much noise to every one of your branch names. I use these:
wip Works in progress; stuff I know won't be finished soon
feat Feature I'm adding or expanding
bug Bug fix or experiment
junk Throwaway branch created to experiment
Each of these tokens can be used to tell you to which part of your workflow each branch belongs.
It sounds like you have multiple branches for different cycles of a change. I do not know what your cycles are, but let's assume they are 'new', 'testing' and 'verified'. You can name your branches with abbreviated versions of these tags, always spelled the same way, to both group them and to remind you which stage you're in.
new/frabnotz
new/foo
new/bar
test/foo
test/frabnotz
ver/foo
You can quickly tell which branches have reached each different stage, and you can group them together easily using Git's pattern matching options.
$ git branch --list "test/*"
test/foo
test/frabnotz
$ git branch --list "*/foo"
new/foo
test/foo
ver/foo
$ gitk --branches="*/foo"
Use slashes to separate parts
You may use most any delimiter you like in branch names, but I find slashes to be the most flexible. You might prefer to use dashes or dots. But slashes let you do some branch renaming when pushing or fetching to/from a remote.
$ git push origin 'refs/heads/feature/*:refs/heads/phord/feat/*'
$ git push origin 'refs/heads/bug/*:refs/heads/review/bugfix/*'
For me, slashes also work better for tab expansion (command completion) in my shell. The way I have it configured I can search for branches with different sub-parts by typing the first characters of the part and pressing the TAB key. Zsh then gives me a list of branches which match the part of the token I have typed. This works for preceding tokens as well as embedded ones.
$ git checkout new<TAB>
Menu: new/frabnotz new/foo new/bar
$ git checkout foo<TAB>
Menu: new/foo test/foo ver/foo
(Zshell is very configurable about command completion and I could also configure it to handle dashes, underscores or dots the same way. But I choose not to.)
It also lets you search for branches in many git commands, like this:
git branch --list "feature/*"
git log --graph --oneline --decorate --branches="feature/*"
gitk --branches="feature/*"
Caveat: As Slipp points out in the comments, slashes can cause problems. Because branches are implemented as paths, you cannot have a branch named "foo" and another branch named "foo/bar". This can be confusing for new users.
Do not use bare numbers
Do not use use bare numbers (or hex numbers) as part of your branch naming scheme. Inside tab-expansion of a reference name, git may decide that a number is part of a sha-1 instead of a branch name. For example, my issue tracker names bugs with decimal numbers. I name my related branches CRnnnnn rather than just nnnnn to avoid confusion.
$ git checkout CR15032<TAB>
Menu: fix/CR15032 test/CR15032
If I tried to expand just 15032, git would be unsure whether I wanted to search SHA-1's or branch names, and my choices would be somewhat limited.
Avoid long descriptive names
Long branch names can be very helpful when you are looking at a list of branches. But it can get in the way when looking at decorated one-line logs as the branch names can eat up most of the single line and abbreviate the visible part of the log.
On the other hand long branch names can be more helpful in "merge commits" if you do not habitually rewrite them by hand. The default merge commit message is Merge branch 'branch-name'
. You may find it more helpful to have merge messages show up as Merge branch 'fix/CR15032/crash-when-unformatted-disk-inserted'
instead of just Merge branch 'fix/CR15032'
.
Make sure you've set your locale settings right before running the script from the shell, e.g.
$ locale -a | grep "^en_.\+UTF-8"
en_GB.UTF-8
en_US.UTF-8
$ export LC_ALL=en_GB.UTF-8
$ export LANG=en_GB.UTF-8
Docs: man locale
, man setlocale
.
I had the same problem but what worked for me was removing this from the Connection String:
persist security info=True
This worked for me
tr "\r" "\n" < sampledata.csv > sampledata2.csv
The situation on macOS is still a bit complicated, but do-able:
Python.org strongly suggest downloading tkinter from ActiveState, but you should read their license first (hint: don't redistribute or want Support).
When the download is opened OS X 10.11 rejected it because it couldn't find my receipt: "ActiveTcl-8.6.pkg can’t be opened because it is from an unidentified developer".
I followed an OSXDaily fix from 2012 which suggested allowing from anywhere. But OS X has now added an "Open Anyway" option to allow (e.g.) Active-Tcl as a once off, and the "Anywhere" option has gained a timeout.
Note that the if $myVar; then ... ;fi
construct has a security problem you might want to avoid with
case $myvar in
(true) echo "is true";;
(false) echo "is false";;
(rm -rf*) echo "I just dodged a bullet";;
esac
You might also want to rethink why if [ "$myvar" = "true" ]
appears awkward to you. It's a shell string comparison that beats possibly forking a process just to obtain an exit status. A fork is a heavy and expensive operation, while a string comparison is dead cheap. Think a few CPU cycles versus several thousand. My case
solution is also handled without forks.
The command I've used:
find . -type d -name "__pycache__" -exec rm -r {} +
Explains:
First finds all __pycache__
folders in current directory.
Execute rm -r {} +
to delete each folder at step above ({}
signify for placeholder and +
to end the command)
Edited 1:
I'm using Linux, to reuse the command I've added the line below to the ~/.bashrc
file
alias rm-pycache='find . -type d -name "__pycache__" -exec rm -r {} +'
Edited 2:
If you're using VS Code, you don't need to remove __pycache__
manually.
You can add the snippet below to settings.json
file. After that, VS Code will hide all __pycache__
folders for you
"files.exclude": {
"**/__pycache__": true
}
Hope it helps !!!
With the release of iOS 7 (September 18th, 2013) apple increased the over-the-air cellular download limit to 100MBs.
Maximum app size remains 2GBs.
With Firefox, I:
swagger.json
definition file there, andBe careful of your slash directions!!
It seems you can drill down in folder structure but not up, annoyingly.
I don't know Mathematica . . . too bad. But I like the answer above, for the most part.
Still there is a major flaw in relying on the stripes alone to glean the answer (I personally don't have a problem with one manual adjustment). There is an example (listed by Brett Champion, here) presented which shows that they, at times, break up the shirt pattern. So then it becomes a more complex pattern.
I would try an approach of shape id and colors, along with spacial relations. Much like face recognition, you could look for geometric patterns at certain ratios from each other. The caveat is that usually one or more of those shapes is occluded.
Get a white balance on the image, and red a red balance from the image. I believe Waldo is always the same value/hue, but the image may be from a scan, or a bad copy. Then always refer to an array of the colors that Waldo actually is: red, white, dark brown, blue, peach, {shoe color}.
There is a shirt pattern, and also the pants, glasses, hair, face, shoes and hat that define Waldo. Also, relative to other people in the image, Waldo is on the skinny side.
So, find random people to obtain an the height of people in this pic. Measure the average height of a bunch of things at random points in the image (a simple outline will produce quite a few individual people). If each thing is not within some standard deviation from each other, they are ignored for now. Compare the average of heights to the image's height. If the ratio is too great (e.g., 1:2, 1:4, or similarly close), then try again. Run it 10(?) of times to make sure that the samples are all pretty close together, excluding any average that is outside some standard deviation. Possible in Mathematica?
This is your Waldo size. Walso is skinny, so you are looking for something 5:1 or 6:1 (or whatever) ht:wd. However, this is not sufficient. If Waldo is partially hidden, the height could change. So, you are looking for a block of red-white that ~2:1. But there has to be more indicators.
Any of those could apply. These are also negative checks against similar people in the pic -- e.g., #2 negates wearing a red-white apron (too close to shoes), #5 eliminates light colored hair. Also, shape is only one indicator for each of these tests . . . color alone within the specified distance can give good results.
This will narrow down the areas to process.
Storing these results will produce a set of areas that should have Waldo in it. Exclude all other areas (e.g., for each area, select a circle twice as big as the average person size), and then run the process that @Heike laid out with removing all but red, and so on.
Any thoughts on how to code this?
Edit:
Thoughts on how to code this . . . exclude all areas but Waldo red, skeletonize the red areas, and prune them down to a single point. Do the same for Waldo hair brown, Waldo pants blue, Waldo shoe color. For Waldo skin color, exclude, then find the outline.
Next, exclude non-red, dilate (a lot) all the red areas, then skeletonize and prune. This part will give a list of possible Waldo center points. This will be the marker to compare all other Waldo color sections to.
From here, using the skeletonized red areas (not the dilated ones), count the lines in each area. If there is the correct number (four, right?), this is certainly a possible area. If not, I guess just exclude it (as being a Waldo center . . . it may still be his hat).
Then check if there is a face shape above, a hair point above, pants point below, shoe points below, and so on.
No code yet -- still reading the docs.
Java 8 provides a set of unsigned long operations that allows you to directly treat those Long variables as unsigned Long, here're some commonly used ones:
And additions, subtractions, and multiplications are the same for signed and unsigned longs.
I had a requirement to provide a report showing details by month where the date field was formatted as date & time, I simply changed the formatting of the date column to "General" and then used the following formula in a new column,
=CONCATENATE(YEAR(C2),MONTH(C2))
If you are creating a code library, then I would use namespace. However, you can still only have one Color enum inside that namespace. If you need an enum that might use a common name, but might have different constants for different classes, use your approach.
This method doesn't call the disambiguation dialog asking you to open either your app or a browser.
If you register the following in your Manifest
<manifest package="com.myApp" .. >
<application ...>
<activity ...>
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.BROWSABLE" />
<data
android:host="gallery"
android:scheme="myApp" />
</intent-filter>
</activity>
..
and click this url from an email on your phone for example
<a href="intent://gallery?directLink=true#Intent;scheme=myApp;package=com.myApp;end">
Click me
</a>
then android will try to find an app with the package com.myApp that responds to your gallery intent and has a myApp scheme. In case it can't, it will take you to the store, looking for com.myApp, which should be your app.
You can use the static method Enum.GetNames
which returns an array representing the names of all the items in the enum. The length property of this array equals the number of items defined in the enum
var myEnumMemberCount = Enum.GetNames(typeof(MyEnum)).Length;
I ran into a similar problem. It works on one server and does not on another server with same Nginx configuration. Found the the solution which is answered by Igor here http://forum.nginx.org/read.php?2,1612,1627#msg-1627
Yes. Or you may combine SSL/non-SSL servers in one server:
server {
listen 80;
listen 443 default ssl;
# ssl on - remember to comment this out
}
A Context represents your environment. It represents the state surrounding where you are in your system.
For example, in web programming in Java, you have a Request, and a Response. These are passed to the service method of a Servlet.
A property of the Servlet is the ServletConfig, and within that is a ServletContext.
The ServletContext is used to tell the servlet about the Container that the Servlet is within.
So, the ServletContext represents the servlets environment within its container.
Similarly, in Java EE, you have EBJContexts that elements (like session beans) can access to work with their containers.
Those are two examples of contexts used in Java today.
Edit --
You mention Android.
Look here: http://developer.android.com/reference/android/content/Context.html
You can see how this Context gives you all sorts of information about where the Android app is deployed and what's available to it.
The size of the numerical types is not defined in the C++ standard, although the minimum sizes are. The way to tell what size they are on your platform is to use numeric limits
For example, the maximum value for a int can be found by:
std::numeric_limits<int>::max();
Computers don't work in base 10, which means that the maximum value will be in the form of 2n-1 because of how the numbers of represent in memory. Take for example eight bits (1 byte)
0100 1000
The right most bit (number) when set to 1 represents 20, the next bit 21, then 22 and so on until we get to the left most bit which if the number is unsigned represents 27.
So the number represents 26 + 23 = 64 + 8 = 72, because the 4th bit from the right and the 7th bit right the left are set.
If we set all values to 1:
11111111
The number is now (assuming unsigned)
128 + 64 + 32 + 16 + 8 + 4 + 2 + 1 = 255 = 28 - 1
And as we can see, that is the largest possible value that can be represented with 8 bits.
On my machine and int and a long are the same, each able to hold between -231 to 231 - 1. In my experience the most common size on modern 32 bit desktop machine.
sudo apt-get install docker # DO NOT do this
is a different library on ubuntu.
Use sudo apt-get install docker-ce
to install the correct docker.
There really seems no way for fooling the <a href= ..
into a POST method. However, given that you have access to CSS of a page, this can be substituted by using a form instead.
Unfortunately, the obvious way of just styling the button in CSS as an anchor tag, is not cross-browser compatible, since different browsers treat <button value= ...
differently.
Incorrect:
<form action='actbusy.php' method='post'>
<button type='submit' name='parameter' value='One'>Two</button>
</form>
The above example will be showing 'Two' and transmit 'parameter:One' in FireFox, while it will show 'One' and transmit also 'parameter:One' in IE8.
The way around is to use hidden input field(s) for delivering data and the button just for submitting it.
<form action='actbusy.php' method='post'>
<input class=hidden name='parameter' value='blaah'>
<button type='submit' name='delete' value='Delete'>Delete</button>
</form>
Note, that this method has a side effect that besides 'parameter:blaah' it will also deliver 'delete:Delete' as surplus parameters in POST.
You want to keep for a button the value attribute and button label between tags both the same ('Delete' on this case), since (as stated above) some browsers will display one and some display another as a button label.
function escapeRegExp(string) {
return string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'); // $& means the whole matched string
}
Example
escapeRegExp("All of these should be escaped: \ ^ $ * + ? . ( ) | { } [ ]");
>>> "All of these should be escaped: \\ \^ \$ \* \+ \? \. \( \) \| \{ \} \[ \] "
(NOTE: the above is not the original answer; it was edited to show the one from MDN. This means it does not match what you will find in the code in the below npm, and does not match what is shown in the below long answer. The comments are also now confusing. My recommendation: use the above, or get it from MDN, and ignore the rest of this answer. -Darren,Nov 2019)
Install
Available on npm as escape-string-regexp
npm install --save escape-string-regexp
Note
See MDN: Javascript Guide: Regular Expressions
Other symbols (~`!@# ...) MAY be escaped without consequence, but are not required to be.
.
.
.
.
escapeRegExp("/path/to/resource.html?search=query");
>>> "\/path\/to\/resource\.html\?search=query"
If you're going to use the function above at least link to this stack overflow post in your code's documentation so that it doesn't look like crazy hard-to-test voodoo.
var escapeRegExp;
(function () {
// Referring to the table here:
// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/regexp
// these characters should be escaped
// \ ^ $ * + ? . ( ) | { } [ ]
// These characters only have special meaning inside of brackets
// they do not need to be escaped, but they MAY be escaped
// without any adverse effects (to the best of my knowledge and casual testing)
// : ! , =
// my test "~!@#$%^&*(){}[]`/=?+\|-_;:'\",<.>".match(/[\#]/g)
var specials = [
// order matters for these
"-"
, "["
, "]"
// order doesn't matter for any of these
, "/"
, "{"
, "}"
, "("
, ")"
, "*"
, "+"
, "?"
, "."
, "\\"
, "^"
, "$"
, "|"
]
// I choose to escape every character with '\'
// even though only some strictly require it when inside of []
, regex = RegExp('[' + specials.join('\\') + ']', 'g')
;
escapeRegExp = function (str) {
return str.replace(regex, "\\$&");
};
// test escapeRegExp("/path/to/res?search=this.that")
}());
A zone transfer is the only way to be sure you have all the subdomain records. If the DNS is correctly configured you should not normally be able to perform an external zone transfer.
The scans.io project has a database of DNS records that can be downloaded and searched for subdomains. This requires downloading the 87GB of DNS data, alternatively you can try the online search of the data at https://hackertarget.com/find-dns-host-records/
Mine was putting the schema on the table Alias by mistake:
SELECT * FROM schema.CustomerOrders co
WHERE schema.co.ID = 1 -- oops!
The assignment operator has lower precedence than &&
, so your condition is equivalent to:
if ((match == 0 && k) = m)
But the left-hand side of this is an rvalue, namely the boolean resulting from the evaluation of the subexpression match == 0 && k
, so you cannot assign to it.
By contrast, comparison has higher precedence, so match == 0 && k == m
is equivalent to:
if ((match == 0) && (k == m))
An example of where the console will return ReferenceError is putting a function inside a JQuery document ready function
//this will fail
$(document).ready(function () {
myFunction(alert('doing something!'));
//other stuff
}
To succeed move the function outside the document ready function
//this will work
myFunction(alert('doing something!'));
$(document).ready(function () {
//other stuff
}
Then in the console window, type the function name with the '()' to execute the function
myFunction()
Also of use is being able to print out the function body to remind yourself what the function does. Do this by leaving off the '()' from the function name
function myFunction(alert('doing something!'))
Of course if you need the function to be registered after the document is loaded then you couldn't do this. But you might be able to work around that.
Try this,
Date currDate = new Date();
DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
String strCurrDate = dateFormat.format(currDate);
System.out.println("strCurrDate->"+strCurrDate);
Some time it's not your eclipse.ini; it's your JDK which is crashed. You can check it by writing following command in a command prompt:
c:\> java -version
If this command shows the following error:
Error occurred during initialization of VM
java/lang/NoClassDefFoundError: java/lang/Object
Then first uninstall JDK and reinstall it.
Eclipse will be in action again ;) As today I have got the same problem, and the above is suggested by Itachi Uchiha.
Just run a simple MySQL query and set the auto increment number to whatever you want.
ALTER TABLE `table_name` AUTO_INCREMENT=10000
In terms of a maximum, as far as I am aware there is not one, nor is there any way to limit such number.
It is perfectly safe, and common practice to set an id number as a primiary key, auto incrementing int. There are alternatives such as using PHP to generate membership numbers for you in a specific format and then checking the number does not exist prior to inserting, however for me personally I'd go with the primary id auto_inc value.
I'm no expert in Bash, but I wonder why this hasn't been proposed:
stdin=$(cat)
echo "$stdin"
One-liner proof that it works for me:
$ fortune | eval 'stdin=$(cat); echo "$stdin"'
If you are using C function fgetc
then you should check a next character whether it is equal to the new line character or to EOF. For example
unsigned int count = 0;
while ( 1 )
{
int c = fgetc( FileStream );
if ( c == EOF || c == '\n' )
{
printF( "The length of the line is %u\n", count );
count = 0;
if ( c == EOF ) break;
}
else
{
++count;
}
}
or maybe it would be better to rewrite the code using do-while loop. For example
unsigned int count = 0;
do
{
int c = fgetc( FileStream );
if ( c == EOF || c == '\n' )
{
printF( "The length of the line is %u\n", count );
count = 0;
}
else
{
++count;
}
} while ( c != EOF );
Of course you need to insert your own processing of read xgaracters. It is only an example how you could use function fgetc
to read lines of a file.
But if the program is written in C++ then it would be much better if you would use std::ifstream
and std::string
classes and function std::getline
to read a whole line.
print date('H:i');
$var = date('H:i');
Should do it, for the current time. Use a lower case h
for 12 hour clock instead of 24 hour.
More date time formats listed here.
I have personally found pywinrm
library to be very effective. However, it does require some commands to be run on the machine and some other setup before it will work.
background:url("img/content-bg.jpg") no-repeat;
background-position:center;
background-size:cover;
or
background-size:100%;
You don't need jQuery, just use javascript's Math.random
function.
edit: If you want to have a number from 1 to 6 show randomly every second, you can do something like this:
<span id="number"></span>
<script language="javascript">
function generate() {
$('#number').text(Math.floor(Math.random() * 6) + 1);
}
setInterval(generate, 1000);
</script>
You can use cut with a delimiter like this:
with space delim:
cut -d " " -f1-100,1000-1005 infile.csv > outfile.csv
with tab delim:
cut -d$'\t' -f1-100,1000-1005 infile.csv > outfile.csv
I gave you the version of cut in which you can extract a list of intervals...
Hope it helps!
This answer is all about authorization and it is a complement of my previous answer about authentication
Why another answer? I attempted to expand my previous answer by adding details on how to support JSR-250 annotations. However the original answer became the way too long and exceeded the maximum length of 30,000 characters. So I moved the whole authorization details to this answer, keeping the other answer focused on performing authentication and issuing tokens.
@Secured
annotationBesides authentication flow shown in the other answer, role-based authorization can be supported in the REST endpoints.
Create an enumeration and define the roles according to your needs:
public enum Role {
ROLE_1,
ROLE_2,
ROLE_3
}
Change the @Secured
name binding annotation created before to support roles:
@NameBinding
@Retention(RUNTIME)
@Target({TYPE, METHOD})
public @interface Secured {
Role[] value() default {};
}
And then annotate the resource classes and methods with @Secured
to perform the authorization. The method annotations will override the class annotations:
@Path("/example")
@Secured({Role.ROLE_1})
public class ExampleResource {
@GET
@Path("{id}")
@Produces(MediaType.APPLICATION_JSON)
public Response myMethod(@PathParam("id") Long id) {
// This method is not annotated with @Secured
// But it's declared within a class annotated with @Secured({Role.ROLE_1})
// So it only can be executed by the users who have the ROLE_1 role
...
}
@DELETE
@Path("{id}")
@Produces(MediaType.APPLICATION_JSON)
@Secured({Role.ROLE_1, Role.ROLE_2})
public Response myOtherMethod(@PathParam("id") Long id) {
// This method is annotated with @Secured({Role.ROLE_1, Role.ROLE_2})
// The method annotation overrides the class annotation
// So it only can be executed by the users who have the ROLE_1 or ROLE_2 roles
...
}
}
Create a filter with the AUTHORIZATION
priority, which is executed after the AUTHENTICATION
priority filter defined previously.
The ResourceInfo
can be used to get the resource Method
and resource Class
that will handle the request and then extract the @Secured
annotations from them:
@Secured
@Provider
@Priority(Priorities.AUTHORIZATION)
public class AuthorizationFilter implements ContainerRequestFilter {
@Context
private ResourceInfo resourceInfo;
@Override
public void filter(ContainerRequestContext requestContext) throws IOException {
// Get the resource class which matches with the requested URL
// Extract the roles declared by it
Class<?> resourceClass = resourceInfo.getResourceClass();
List<Role> classRoles = extractRoles(resourceClass);
// Get the resource method which matches with the requested URL
// Extract the roles declared by it
Method resourceMethod = resourceInfo.getResourceMethod();
List<Role> methodRoles = extractRoles(resourceMethod);
try {
// Check if the user is allowed to execute the method
// The method annotations override the class annotations
if (methodRoles.isEmpty()) {
checkPermissions(classRoles);
} else {
checkPermissions(methodRoles);
}
} catch (Exception e) {
requestContext.abortWith(
Response.status(Response.Status.FORBIDDEN).build());
}
}
// Extract the roles from the annotated element
private List<Role> extractRoles(AnnotatedElement annotatedElement) {
if (annotatedElement == null) {
return new ArrayList<Role>();
} else {
Secured secured = annotatedElement.getAnnotation(Secured.class);
if (secured == null) {
return new ArrayList<Role>();
} else {
Role[] allowedRoles = secured.value();
return Arrays.asList(allowedRoles);
}
}
}
private void checkPermissions(List<Role> allowedRoles) throws Exception {
// Check if the user contains one of the allowed roles
// Throw an Exception if the user has not permission to execute the method
}
}
If the user has no permission to execute the operation, the request is aborted with a 403
(Forbidden).
To know the user who is performing the request, see my previous answer. You can get it from the SecurityContext
(which should be already set in the ContainerRequestContext
) or inject it using CDI, depending on the approach you go for.
If a @Secured
annotation has no roles declared, you can assume all authenticated users can access that endpoint, disregarding the roles the users have.
Alternatively to defining the roles in the @Secured
annotation as shown above, you could consider JSR-250 annotations such as @RolesAllowed
, @PermitAll
and @DenyAll
.
JAX-RS doesn't support such annotations out-of-the-box, but it could be achieved with a filter. Here are a few considerations to keep in mind if you want to support all of them:
@DenyAll
on the method takes precedence over @RolesAllowed
and @PermitAll
on the class.@RolesAllowed
on the method takes precedence over @PermitAll
on the class.@PermitAll
on the method takes precedence over @RolesAllowed
on the class.@DenyAll
can't be attached to classes.@RolesAllowed
on the class takes precedence over @PermitAll
on the class.So an authorization filter that checks JSR-250 annotations could be like:
@Provider
@Priority(Priorities.AUTHORIZATION)
public class AuthorizationFilter implements ContainerRequestFilter {
@Context
private ResourceInfo resourceInfo;
@Override
public void filter(ContainerRequestContext requestContext) throws IOException {
Method method = resourceInfo.getResourceMethod();
// @DenyAll on the method takes precedence over @RolesAllowed and @PermitAll
if (method.isAnnotationPresent(DenyAll.class)) {
refuseRequest();
}
// @RolesAllowed on the method takes precedence over @PermitAll
RolesAllowed rolesAllowed = method.getAnnotation(RolesAllowed.class);
if (rolesAllowed != null) {
performAuthorization(rolesAllowed.value(), requestContext);
return;
}
// @PermitAll on the method takes precedence over @RolesAllowed on the class
if (method.isAnnotationPresent(PermitAll.class)) {
// Do nothing
return;
}
// @DenyAll can't be attached to classes
// @RolesAllowed on the class takes precedence over @PermitAll on the class
rolesAllowed =
resourceInfo.getResourceClass().getAnnotation(RolesAllowed.class);
if (rolesAllowed != null) {
performAuthorization(rolesAllowed.value(), requestContext);
}
// @PermitAll on the class
if (resourceInfo.getResourceClass().isAnnotationPresent(PermitAll.class)) {
// Do nothing
return;
}
// Authentication is required for non-annotated methods
if (!isAuthenticated(requestContext)) {
refuseRequest();
}
}
/**
* Perform authorization based on roles.
*
* @param rolesAllowed
* @param requestContext
*/
private void performAuthorization(String[] rolesAllowed,
ContainerRequestContext requestContext) {
if (rolesAllowed.length > 0 && !isAuthenticated(requestContext)) {
refuseRequest();
}
for (final String role : rolesAllowed) {
if (requestContext.getSecurityContext().isUserInRole(role)) {
return;
}
}
refuseRequest();
}
/**
* Check if the user is authenticated.
*
* @param requestContext
* @return
*/
private boolean isAuthenticated(final ContainerRequestContext requestContext) {
// Return true if the user is authenticated or false otherwise
// An implementation could be like:
// return requestContext.getSecurityContext().getUserPrincipal() != null;
}
/**
* Refuse the request.
*/
private void refuseRequest() {
throw new AccessDeniedException(
"You don't have permissions to perform this action.");
}
}
Note: The above implementation is based on the Jersey RolesAllowedDynamicFeature
. If you use Jersey, you don't need to write your own filter, just use the existing implementation.
In my opinion, it's a way to implement currying in python.
from functools import partial
def add(a,b):
return a + b
def add2number(x,y,z):
return x + y + z
if __name__ == "__main__":
add2 = partial(add,2)
print("result of add2 ",add2(1))
add3 = partial(partial(add2number,1),2)
print("result of add3",add3(1))
The result is 3 and 4.
I would go with Swing. For layout I would use JGoodies form layout. Its worth studying the white paper on the Form Layout here - http://www.jgoodies.com/freeware/forms/
Also if you are going to start developing a huge desktop application, you will definitely need a framework. Others have pointed out the netbeans framework. I didnt like it much so wrote a new one that we now use in my company. I have put it onto sourceforge, but didnt find the time to document it much. Here's the link to browse the code:
http://swingobj.svn.sourceforge.net/viewvc/swingobj/
The showcase should show you how to do a simple logon actually..
Let me know if you have any questions on it I could help.
Someone will give you a better answe than this possibly, but one thing I tend to do is if all my numeric data are int64
or float64
objects, then you can create a dict of the column data types and then use the values to create your list of columns.
So for example, in a dataframe where I have columns of type float64
, int64
and object
firstly you can look at the data types as so:
DF.dtypes
and if they conform to the standard whereby the non-numeric columns of data are all object
types (as they are in my dataframes), then you can do the following to get a list of the numeric columns:
[key for key in dict(DF.dtypes) if dict(DF.dtypes)[key] in ['float64', 'int64']]
Its just a simple list comprehension. Nothing fancy. Again, though whether this works for you will depend upon how you set up you dataframe...
Factory Method relies on inheritance: Object creation is delegated to subclasses, which implement the factory method to create objects.
Abstract Factory relies on object composition: object creation is implemented in methods exposed in the factory interface.
High level diagram of Factory and Abstract factory pattern,
For more information about the Factory method, refer this article.
For more information about Abstract factory method, refer this article.
A temporary solution if you don't want to get into the x
, y
position of your title.
Following worked for me.
plt.title('Capital Expenditure\n') # Add a next line after your title
kudos.
You want:
dir > a.txt 2>&1
The syntax 2>&1
will redirect 2
(stderr) to 1
(stdout). You can also hide messages by redirecting to NUL
, more explanation and examples on MSDN.
The full list of readyState
values is:
State Description
0 The request is not initialized
1 The request has been set up
2 The request has been sent
3 The request is in process
4 The request is complete
(from https://www.w3schools.com/js/js_ajax_http_response.asp)
In practice you almost never use any of them except for 4.
Some XMLHttpRequest implementations may let you see partially received responses in responseText
when readyState==3
, but this isn't universally supported and shouldn't be relied upon.
The SVN cleanup didn't work. The SVN folder on my local system got corrupted. So I just deleted the folder, recreated a new one, and updated from SVN. That solved the problem!
No they do not exist in C# 3.0 and will not be added in 4.0. It's on the list of feature wants for C# so it may be added at a future date.
At this point the best you can do is GetXXX style extension methods.
First of all, you need to check that the IIS is installed in your machine, for that you can go to:
Control Panel --> Add or Remove Programs --> Windows Features --> And Check if Internet Information Services is installed with at least the 'Web Administration Tools' Enabled and The 'World Wide Web Service'
If not, check it, and Press Accept to install it.
Once that is done, you need to go to Administrative Tools in Control Panel and the IIS Will be there. Or simply run inetmgr (after Win+R).
Edit: You should have something like this:
I wonder if it might be worth using PHP (or another server-side scripting language) or Javascript to truncate the strings to the right length (although calculating the right length is tricky, unless you use a fixed-width font)?
Much like leonardocsouza, I had the same problem. To clarify a bit, this is what my folder structure looked like when I ran node server.js
node_modules/
app/
index.html
server.js
After printing out the __dirname
path, I realized that the __dirname
path was where my server was running (app/
).
So, the answer to your question is this:
If your server.js
file is in the same folder as the files you are trying to render, then
app.use( express.static( path.join( application_root, 'site') ) );
should actually be
app.use(express.static(application_root));
The only time you would want to use the original syntax that you had would be if you had a folder tree like so:
app/
index.html
node_modules
server.js
where index.html
is in the app/
directory, whereas server.js
is in the root directory (i.e. the same level as the app/
directory).
Side note: Intead of calling the path
utility, you can use the syntax application_root + 'site'
to join a path.
Overall, your code could look like:
// Module dependencies.
var application_root = __dirname,
express = require( 'express' ), //Web framework
mongoose = require( 'mongoose' ); //MongoDB integration
//Create server
var app = express();
// Configure server
app.configure( function() {
//Don't change anything here...
//Where to serve static content
app.use( express.static( application_root ) );
//Nothing changes here either...
});
//Start server --- No changes made here
var port = 5000;
app.listen( port, function() {
console.log( 'Express server listening on port %d in %s mode', port, app.settings.env );
});
USE DataBaseName; GO --------- CREATE ROLE --------- CREATE ROLE Doctors ; GO ---- Assign Role To users ------- CREATE USER [Username] FOR LOGIN [Domain\Username] EXEC sp_addrolemember N'Doctors', N'Username' ----- GRANT Permission to Users Assinged with this Role----- GRANT ALL ON Table1, Table2, Table3 TO Doctors; GO
if your list looks like this: [1,2,3] you can do:
lst = [1,2,3]
df = pd.DataFrame([lst])
df.columns =['col1','col2','col3']
df
to get this:
col1 col2 col3
0 1 2 3
alternatively you can create a column as follows:
import numpy as np
df = pd.DataFrame(np.array([lst]).T)
df.columns =['col1']
df
to get this:
col1
0 1
1 2
2 3
SELECT chargeId, chargeType, MAX(serviceMonth) AS serviceMonth
FROM invoice
GROUP BY chargeId, chargeType
How do I check if something is (not) in a list in Python?
The cheapest and most readable solution is using the in
operator (or in your specific case, not in
). As mentioned in the documentation,
The operators
in
andnot in
test for membership.x in s
evaluates toTrue
ifx
is a member ofs
, andFalse
otherwise.x not in s
returns the negation ofx in s
.
Additionally,
The operator
not in
is defined to have the inverse true value ofin
.
y not in x
is logically the same as not y in x
.
Here are a few examples:
'a' in [1, 2, 3]
# False
'c' in ['a', 'b', 'c']
# True
'a' not in [1, 2, 3]
# True
'c' not in ['a', 'b', 'c']
# False
This also works with tuples, since tuples are hashable (as a consequence of the fact that they are also immutable):
(1, 2) in [(3, 4), (1, 2)]
# True
If the object on the RHS defines a __contains__()
method, in
will internally call it, as noted in the last paragraph of the Comparisons section of the docs.
...
in
andnot in
, are supported by types that are iterable or implement the__contains__()
method. For example, you could (but shouldn't) do this:
[3, 2, 1].__contains__(1)
# True
in
short-circuits, so if your element is at the start of the list, in
evaluates faster:
lst = list(range(10001))
%timeit 1 in lst
%timeit 10000 in lst # Expected to take longer time.
68.9 ns ± 0.613 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)
178 µs ± 5.01 µs per loop (mean ± std. dev. of 7 runs, 10000 loops each)
If you want to do more than just check whether an item is in a list, there are options:
list.index
can be used to retrieve the index of an item. If that element does not exist, a ValueError
is raised.list.count
can be used if you want to count the occurrences.set
s?Ask yourself these questions:
hash
on them?If you answered "yes" to these questions, you should be using a set
instead. An in
membership test on list
s is O(n) time complexity. This means that python has to do a linear scan of your list, visiting each element and comparing it against the search item. If you're doing this repeatedly, or if the lists are large, this operation will incur an overhead.
set
objects, on the other hand, hash their values for constant time membership check. The check is also done using in
:
1 in {1, 2, 3}
# True
'a' not in {'a', 'b', 'c'}
# False
(1, 2) in {('a', 'c'), (1, 2)}
# True
If you're unfortunate enough that the element you're searching/not searching for is at the end of your list, python will have scanned the list upto the end. This is evident from the timings below:
l = list(range(100001))
s = set(l)
%timeit 100000 in l
%timeit 100000 in s
2.58 ms ± 58.9 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
101 ns ± 9.53 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)
As a reminder, this is a suitable option as long as the elements you're storing and looking up are hashable. IOW, they would either have to be immutable types, or objects that implement __hash__
.
My solution, it´s make with jquery-chosen and bootstrap, the id is for jquery chosen, tested and working, I had problems concatenating @foreach but now work with a double @foreach and double @if:
<div class="form-group">
<label for="tagLabel">Tags: </label>
<select multiple class="chosen-tag" id="tagLabel" name="tag_id[]" required>
@foreach($tags as $id => $name)
@if (is_array(Request::old('tag_id')))
<option value="{{ $id }}"
@foreach (Request::old('tag_id') as $idold)
@if($idold==$id)
selected
@endif
@endforeach
style="padding:5px;">{{ $name }}</option>
@else
<option value="{{ $id }}" style="padding:5px;">{{ $name }}</option>
@endif
@endforeach
</select>
</div>
this is the code por jquery chosen (the blade.php code doesn´t need this code to work)
$(".chosen-tag").chosen({
placeholder_text_multiple: "Selecciona alguna etiqueta",
no_results_text: "No hay resultados para la busqueda",
search_contains: true,
width: '500px'
});
Give Icomoon a try. You can upload your own SVGs, add them to the library, then create a custom font combining FontAwesome with your own icons.
You can pass in the data to be used in the mouseover like this- the mouseover event uses a function with your previously enter
ed data as an argument (and the index as a second argument) so you don't need to use enter()
a second time.
vis.selectAll("circle")
.data(datafiltered).enter().append("svg:circle")
.attr("cx", function(d) { return x(d.x);})
.attr("cy", function(d) {return y(d.y)})
.attr("fill", "red").attr("r", 15)
.on("mouseover", function(d,i) {
d3.select(this).append("text")
.text( d.x)
.attr("x", x(d.x))
.attr("y", y(d.y));
});
As far as I'm aware in order to format a date value you have to handle it in parameterMap,
$('#listDiv').kendoGrid({
dataSource: {
type: 'json',
serverPaging: true,
pageSize: 10,
transport: {
read: {
url: '@Url.Action("_ListMy", "Placement")',
data: refreshGridParams,
type: 'POST'
},
parameterMap: function (options, operation) {
if (operation != "read") {
var d = new Date(options.StartDate);
options.StartDate = kendo.toString(new Date(d), "dd/MM/yyyy");
return options;
}
else { return options; }
}
},
schema: {
model: {
id: 'Id',
fields: {
Id: { type: 'number' },
StartDate: { type: 'date', format: 'dd/MM/yyyy' },
Area: { type: 'string' },
Length: { type: 'string' },
Display: { type: 'string' },
Status: { type: 'string' },
Edit: { type: 'string' }
}
},
data: "Data",
total: "Count"
}
},
scrollable: false,
columns:
[
{
field: 'StartDate',
title: 'Start Date',
format: '{0:dd/MM/yyyy}',
width: 100
},
If you follow the above example and just renames objects like 'StartDate' then it should work (ignore 'data: refreshGridParams,')
For further details check out below link or just search for kendo grid parameterMap ans see what others have done.
http://docs.kendoui.com/api/framework/datasource#configuration-transport.parameterMap
You want to do this:
git add -u
git reset HEAD path/to/file
git commit
Be sure and do this from the top level of the repo; add -u
adds changes in the current directory (recursively).
The key line tells git to reset the version of the given path in the index (the staging area for the commit) to the version from HEAD (the currently checked-out commit).
And advance warning of a gotcha for others reading this: add -u
stages all modifications, but doesn't add untracked files. This is the same as what commit -a
does. If you want to add untracked files too, use add .
to recursively add everything.
rows = int(input('How many stars in each row do you want?'))
columns = int(input('How many columns do you want?'))
i = 0
for i in range(columns):
print ("*" * rows)
i = i + 1
Hope this is work, this is working in my app
SmsManager.getDefault().sendTextMessage("Phone Number", null, "Message", null, null);
You need to use the requireGestureRecognizerToFail: method. Something like this:
[singleTapRecognizer requireGestureRecognizerToFail:doubleTapRecognizer];
You only need to calculate it for IE7 and older (and only if your content doesn't have fixed size). I suggest using HTML conditional comments to limit hack to old IEs that don't support CSS2. For all other browsers use this:
<style type="text/css">
html,body {display:table; height:100%;width:100%;margin:0;padding:0;}
body {display:table-cell; vertical-align:middle;}
div {display:table; margin:0 auto; background:red;}
</style>
<body><div>test<br>test</div></body>
This is the perfect solution. It centers <div>
of any size, and shrink-wraps it to size of its content.
You can use JavaMail API to handle your email tasks. JavaMail API is available in JavaEE package and its jar is available for download. Sadly it cannot be used directly in an Android application since it uses AWT components which are completely incompatible in Android.
You can find the Android port for JavaMail at the following location: http://code.google.com/p/javamail-android/
Add the jars to your application and use the SMTP method
The normal solution to this is to pass an instance of the context to the class as you create it, or after it is first created but before you need to use the context.
Another solution is to create an Application object with a static method to access the application context although that couples the Droid object fairly tightly into the code.
Edit, examples added
Either modify the Droid class to be something like this
public Droid(Context context,int x, int y) {
this.bitmap = BitmapFactory.decodeResource(context.getResources(), R.drawable.birdpic);
this.x = x;
this.y = y;
}
Or create an Application something like this:
public class App extends android.app.Application
{
private static App mApp = null;
/* (non-Javadoc)
* @see android.app.Application#onCreate()
*/
@Override
public void onCreate()
{
super.onCreate();
mApp = this;
}
public static Context context()
{
return mApp.getApplicationContext();
}
}
And call App.context() wherever you need a context - note however that not all functions are available on an application context, some are only available on an activity context but it will certainly do with your need for getResources().
Please note that you'll need to add android:name to your application definition in your manifest, something like this:
<application
android:icon="@drawable/icon"
android:label="@string/app_name"
android:name=".App" >
What you mean is either
SELECT DISTINCT a, b FROM pairs;
or
SELECT a, b FROM pairs GROUP BY a, b;
You can set this bookmarklet in your "Bookmarks Bar" in order to have Firebug lite always available in Chrome/Chromium browser (put this as the URL):
javascript:var firebug=document.createElement('script');firebug.setAttribute('src','http://getfirebug.com/releases/lite/1.2/firebug-lite-compressed.js');document.body.appendChild(firebug);(function(){if(window.firebug.version){firebug.init();}else{setTimeout(arguments.callee);}})();void(firebug);
I would consider .pop()
to be the most 'correct' solution, however, sometimes it might not work since you need to use array without the last element right there...
In such a case you might want to use the following, it will return [1,2,3]
var arr = [1,2,3,4];_x000D_
console.log(arr.splice(0,arr.length-1));
_x000D_
while .pop()
would return 4
:
var arr = [1,2,3,4];_x000D_
console.log(arr.pop());
_x000D_
which might not be desirable...
Hope this saves you some time.
Was missing the use of calc
in the answers, which is a cleaner solution.
#logo {
position: absolute;
left: calc(50% - 25px);
height: 50px;
width: 50px;
background: red;
}
Works in most modern browsers: http://caniuse.com/calc
Maybe it's too soon to use it without a fallback, but I thought maybe for future visitors it would be helpful.
Adding to @Patrick's answer, you can use the following to drop multiple columns
columns_to_drop = ['id', 'id_copy']
df = df.drop(*columns_to_drop)
$value = ( array_key_exists($key, $array) && !empty($array[$key]) )
? $array[$key]
: 'non-existant or empty value key';
You can delete the file using
unlink($Your_file_path);
but if you are deleting a file from it's http path then this unlink is not work proper. You have to give a file path correct.
You could do it yourself (thats what I did) - in order to not be bothered with exception handling, you simply extend the RuntimeException, your class could look something like this:
public class NotImplementedException extends RuntimeException {
private static final long serialVersionUID = 1L;
public NotImplementedException(){}
}
You could extend it to take a message - but if you use the method as I do (that is, as a reminder, that there is still something to be implemented), then usually there is no need for additional messages.
I dare say, that I only use this method, while I am in the process of developing a system, makes it easier for me to not lose track of which methods are still not implemented properly :)
INSERT INTO tablename
(name, salary)
VALUES
('Bob', 1125),
('Jane', 1200),
('Frank', 1100),
('Susan', 1175),
('John', 1150)
ON DUPLICATE KEY UPDATE salary = VALUES(salary);
One of the best compressors (not specifically an obfuscator) is the YUI Compressor.
That's because they use an icon font for the buttons. They use "Slick" font as you can see in this image:
Basically, the make the letter "A" the form of an icon, the letter "B" the form of another one and so on.
For example:
If you want to know more about icon fonts click here
If you want to change the icons, you need to replace the whole button code or you can go to www.fontastic.me and create your own icon font. After that, replace the font file for the current one and you'll have your own icon.
How about
sub foo()
dim r As Range, rows As Long, i As Long
Set r = ActiveSheet.Range("A1:Z50")
rows = r.rows.Count
For i = rows To 1 Step (-1)
If WorksheetFunction.CountA(r.rows(i)) = 0 Then r.rows(i).Delete
Next
End Sub
Try this
Option Explicit
Sub Sample()
Dim i As Long
Dim DelRange As Range
On Error GoTo Whoa
Application.ScreenUpdating = False
For i = 1 To 50
If Application.WorksheetFunction.CountA(Range("A" & i & ":" & "Z" & i)) = 0 Then
If DelRange Is Nothing Then
Set DelRange = Range("A" & i & ":" & "Z" & i)
Else
Set DelRange = Union(DelRange, Range("A" & i & ":" & "Z" & i))
End If
End If
Next i
If Not DelRange Is Nothing Then DelRange.Delete shift:=xlUp
LetsContinue:
Application.ScreenUpdating = True
Exit Sub
Whoa:
MsgBox Err.Description
Resume LetsContinue
End Sub
IF you want to delete the entire row then use this code
Option Explicit
Sub Sample()
Dim i As Long
Dim DelRange As Range
On Error GoTo Whoa
Application.ScreenUpdating = False
For i = 1 To 50
If Application.WorksheetFunction.CountA(Range("A" & i & ":" & "Z" & i)) = 0 Then
If DelRange Is Nothing Then
Set DelRange = Rows(i)
Else
Set DelRange = Union(DelRange, Rows(i))
End If
End If
Next i
If Not DelRange Is Nothing Then DelRange.Delete shift:=xlUp
LetsContinue:
Application.ScreenUpdating = True
Exit Sub
Whoa:
MsgBox Err.Description
Resume LetsContinue
End Sub
You can't do it with only the standard library as the standard library doesn't have any timezones. You need pytz or dateutil.
>>> from datetime import datetime
>>> now = datetime.utcnow()
>>> from dateutil import tz
>>> HERE = tz.tzlocal()
>>> UTC = tz.gettz('UTC')
The Conversion:
>>> gmt = now.replace(tzinfo=UTC)
>>> gmt.astimezone(HERE)
datetime.datetime(2010, 12, 30, 15, 51, 22, 114668, tzinfo=tzlocal())
Or well, you can do it without pytz or dateutil by implementing your own timezones. But that would be silly.
Check you have the line:
import org.json.JSONArray;
at the top of your source code
There is a property in <Button>
that is android:textAllCaps="false" that make characters in which you want in your own Small and caps. By Default its became True so write this code and make textAllCaps=false then you can write text on button in small and Caps letter as per your requirement.
Complete code for a Button which allow use to write letters as per our requirement.
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/btnLogin"
android:text="Login for Chat"
android:textAllCaps="false"/>
<p>
indicates a paragraph and has semantic meaning.
<div>
is simply a block container for other content.
Anything that can go in a <p>
can go in a <div>
but the reverse is not true. <div>
tags can have block-level elements as children. <p>
elements cannot.
Tae a look at the HTML DTD.
<!ENTITY % inline "#PCDATA | %fontstyle; | %phrase; | %special; | %formctrl;"> <!ENTITY % block "P | %heading; | %list; | %preformatted; | DL | DIV | NOSCRIPT | BLOCKQUOTE | FORM | HR | TABLE | FIELDSET | ADDRESS"> <!ENTITY % flow "%block; | %inline;"> <!ELEMENT DIV - - (%flow;)* -- generic language/style container --> <!ELEMENT P - O (%inline;)* -- paragraph -->
You switch to:
json_decode($response->getBody(), true)
Instead of the other comment if you want it to work exactly as before in order to get arrays instead of objects.
The toString() method of Selenium's By-Class produces something like "By.xpath: //XpathFoo"
So you could take a substring starting at the colon with something like this:
String selector = divA.toString().substring(s.indexOf(":") + 2);
With this, you could find your element inside your other element with this:
WebElement input = driver.findElement( By.xpath( selector + "//input" ) );
Advantage: You have to search only once on the actual SUT, so it could give you a bonus in performance.
Disadvantage: Ugly... if you want to search for the parent element with css selectory and use xpath for it's childs, you have to check for types before you concatenate... In this case, Slanec's solution (using findElement on a WebElement) is much better.
The best solution for your problem is to utilize a Pool
. Using Queue
s and having a separate "queue feeding" functionality is probably overkill.
Here's a slightly rearranged version of your program, this time with only 2 processes coralled in a Pool
. I believe it's the easiest way to go, with minimal changes to original code:
import multiprocessing
import time
data = (
['a', '2'], ['b', '4'], ['c', '6'], ['d', '8'],
['e', '1'], ['f', '3'], ['g', '5'], ['h', '7']
)
def mp_worker((inputs, the_time)):
print " Processs %s\tWaiting %s seconds" % (inputs, the_time)
time.sleep(int(the_time))
print " Process %s\tDONE" % inputs
def mp_handler():
p = multiprocessing.Pool(2)
p.map(mp_worker, data)
if __name__ == '__main__':
mp_handler()
Note that mp_worker()
function now accepts a single argument (a tuple of the two previous arguments) because the map()
function chunks up your input data into sublists, each sublist given as a single argument to your worker function.
Output:
Processs a Waiting 2 seconds
Processs b Waiting 4 seconds
Process a DONE
Processs c Waiting 6 seconds
Process b DONE
Processs d Waiting 8 seconds
Process c DONE
Processs e Waiting 1 seconds
Process e DONE
Processs f Waiting 3 seconds
Process d DONE
Processs g Waiting 5 seconds
Process f DONE
Processs h Waiting 7 seconds
Process g DONE
Process h DONE
Edit as per @Thales comment below:
If you want "a lock for each pool limit" so that your processes run in tandem pairs, ala:
A waiting B waiting | A done , B done | C waiting , D waiting | C done, D done | ...
then change the handler function to launch pools (of 2 processes) for each pair of data:
def mp_handler():
subdata = zip(data[0::2], data[1::2])
for task1, task2 in subdata:
p = multiprocessing.Pool(2)
p.map(mp_worker, (task1, task2))
Now your output is:
Processs a Waiting 2 seconds
Processs b Waiting 4 seconds
Process a DONE
Process b DONE
Processs c Waiting 6 seconds
Processs d Waiting 8 seconds
Process c DONE
Process d DONE
Processs e Waiting 1 seconds
Processs f Waiting 3 seconds
Process e DONE
Process f DONE
Processs g Waiting 5 seconds
Processs h Waiting 7 seconds
Process g DONE
Process h DONE
You don't really need to do anything manually, await
keyword pauses the function execution until blah()
returns.
private async void SomeFunction()
{
var x = await LoadBlahBlah(); <- Function is not paused
//rest of the code get's executed even if LoadBlahBlah() is still executing
}
private async Task<T> LoadBlahBlah()
{
await DoStuff(); <- function is paused
await DoMoreStuff();
}
T
is type of object blah()
returns
You can't really await
a void
function so LoadBlahBlah()
cannot be void
If you want to ignore the insertion of existing value, there must be a Key field in your Table. Just create a table With Primary Key Field Like:
CREATE TABLE IF NOT EXISTS TblUsers (UserId INTEGER PRIMARY KEY, UserName varchar(100), ContactName varchar(100),Password varchar(100));
And Then Insert Or Replace / Insert Or Ignore Query on the Table Like:
INSERT OR REPLACE INTO TblUsers (UserId, UserName, ContactName ,Password) VALUES('1','UserName','ContactName','Password');
It Will Not Let it Re-Enter The Existing Primary key Value... This Is how you can Check Whether a Value exists in the table or not.
The simplest solution is create a JavaScript function and call it for the Ajax success
callback.
function callServerAsync(){
$.ajax({
url: '...',
success: function(response) {
successCallback(response);
}
});
}
function successCallback(responseObj){
// Do something like read the response and show data
alert(JSON.stringify(responseObj)); // Only applicable to JSON response
}
function foo(callback) {
$.ajax({
url: '...',
success: function(response) {
return callback(null, response);
}
});
}
var result = foo(function(err, result){
if (!err)
console.log(result);
});
var a=dateString.split(" ");
var b=a[0].split("-");
var c=a[1].split(":");
var date = new Date(b[0],(b[1]-1),b[2],b[0],c[1],c[2]);
I was facing similar problem this weekend. Tried all the above mentioned tricks, but none of them worked of me. (Working in Eclipse LUNA)
Then i analysed that just before creating a particular servlet, i was running Apache Tomcat v7.0 successfully. Which was "RefreshServlet" as shown below :
So that practicing servlets to understand the "AutoRefresh" functioning. When i remove this servlet from my application, it works fine, but when i try to add and run this servlet, it gives the same error "Apache Tomcat v7.0 failed to start"
Don't know why, but only removing this servlet works fine for me to run the rest of my application.
So, the bottom line suggestion from me would be that if not any other trick is working, then try removing any latest servlet or any class you just created before getting this error and it may work fine for you too for the rest of the application.
Any further explanation would be appreciated. Thanks
To pass a string to the view as the Model, you can do:
public ActionResult Index()
{
string myString = "This is my string";
return View((object)myString);
}
You must cast it to an object so that MVC doesn't try to load the string as the view name, but instead pass it as the model. You could also write:
return View("Index", myString);
.. which is a bit more verbose.
Then in your view, just type it as a string:
@model string
<p>Value: @Model</p>
Then you can manipulate Model how you want.
For accessing it from a Layout page, it might be better to create an HtmlExtension for this:
public static string GetThemePath(this HtmlHelper helper)
{
return "/path-to-theme";
}
Then inside your layout page:
<p>Value: @Html.GetThemePath()</p>
Hopefully you can apply this to your own scenario.
Edit: explicit HtmlHelper code:
namespace <root app namespace>
{
public static class Helpers
{
public static string GetThemePath(this HtmlHelper helper)
{
return System.Web.Hosting.HostingEnvironment.MapPath("~") + "/path-to-theme";
}
}
}
Then in your view:
@{
var path = Html.GetThemePath();
// .. do stuff
}
Or:
<p>Path: @Html.GetThemePath()</p>
Edit 2:
As discussed, the Helper will work if you add a @using
statement to the top of your view, with the namespace pointing to the one that your helper is in.
Hmm i was having some trouble with that part (yes still xD):
xl.Application.Run("excelsheet.xlsm!macroname.macroname")
cos im not using excel often (same with vb or macros, but i need it to use femap with python) so i finaly resolved it checking macro list:
Developer -> Macros:
there i saw that: this macroname.macroname
should be sheet_name.macroname
like in "Macros" list.
(i spend something like 30min-1h trying to solve it, so it may be helpful for noobs like me in excel) xD
I refined the bash solution a bit, so that the more efficient scan is used instead of keys, and printing out array and hash values is supported. My solution also prints out the key name.
redis_print.sh:
#!/bin/bash
# Default to '*' key pattern, meaning all redis keys in the namespace
REDIS_KEY_PATTERN="${REDIS_KEY_PATTERN:-*}"
for key in $(redis-cli --scan --pattern "$REDIS_KEY_PATTERN")
do
type=$(redis-cli type $key)
if [ $type = "list" ]
then
printf "$key => \n$(redis-cli lrange $key 0 -1 | sed 's/^/ /')\n"
elif [ $type = "hash" ]
then
printf "$key => \n$(redis-cli hgetall $key | sed 's/^/ /')\n"
else
printf "$key => $(redis-cli get $key)\n"
fi
done
Note: you can formulate a one-liner of this script by removing the first line of redis_print.sh and commanding: cat redis_print.sh | tr '\n' ';' | awk '$1=$1'
The error is simply asking you to insert a Middleware in between which would help to handle async operations.
You could do that by :
npm i redux-thunk
Inside index.js
import thunk from "redux-thunk"
...createStore(rootReducers, applyMiddleware(thunk));
Now, async operations will work inside your functions.
This is done with
ANALYZE TABLE table_name;
Read more about it here.
ANALYZE TABLE analyzes and stores the key distribution for a table. During the analysis, the table is locked with a read lock for MyISAM, BDB, and InnoDB. This statement works with MyISAM, BDB, InnoDB, and NDB tables.
I worked the same problem for showing multiple markers in Kotlin using a fragment
first declare a list of markers
private lateinit var markers: MutableList<Marker>
initialize this in the oncreate method of the frament
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
//initialize markers list
markers = mutableListOf()
return inflater.inflate(R.layout.fragment_driver_map, container, false)
}
on the OnMapReadyCallback add the markers to the markers list
private val callback = OnMapReadyCallback { googleMap ->
map = googleMap
markers.add(
map.addMarker(
MarkerOptions().position(riderLatLng)
.title("Driver")
.snippet("Driver")
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED))))
markers.add(
map.addMarker(
MarkerOptions().position(driverLatLng)
.title("Driver")
.snippet("Driver")
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN))))
Still on the callback
//create builder
val builder = LatLngBounds.builder()
//loop through the markers list
for (marker in markers) {
builder.include(marker.position)
}
//create a bound
val bounds = builder.build()
//set a 200 pixels padding from the edge of the screen
val cu = CameraUpdateFactory.newLatLngBounds(bounds,200)
//move and animate the camera
map.moveCamera(cu)
//animate camera by providing zoom and duration args, callBack set to null
map.animateCamera(CameraUpdateFactory.zoomTo(10f), 2000, null)
Merry coding guys
You can simplify it to
if ($user_sam -and $user_case) {
...
}
because empty strings coerce to $false
(and so does $null
, for that matter).
So at the most basic level a HANDLE of any sort is a pointer to a pointer or
#define HANDLE void **
Now as to why you would want to use it
Lets take a setup:
class Object{
int Value;
}
class LargeObj{
char * val;
LargeObj()
{
val = malloc(2048 * 1000);
}
}
void foo(Object bar){
LargeObj lo = new LargeObj();
bar.Value++;
}
void main()
{
Object obj = new Object();
obj.val = 1;
foo(obj);
printf("%d", obj.val);
}
So because obj was passed by value (make a copy and give that to the function) to foo, the printf will print the original value of 1.
Now if we update foo to:
void foo(Object * bar)
{
LargeObj lo = new LargeObj();
bar->val++;
}
There is a chance that the printf will print the updated value of 2. But there is also the possibility that foo will cause some form of memory corruption or exception.
The reason is this while you are now using a pointer to pass obj to the function you are also allocating 2 Megs of memory, this could cause the OS to move the memory around updating the location of obj. Since you have passed the pointer by value, if obj gets moved then the OS updates the pointer but not the copy in the function and potentially causing problems.
A final update to foo of:
void foo(Object **bar){
LargeObj lo = LargeObj();
Object * b = &bar;
b->val++;
}
This will always print the updated value.
See, when the compiler allocates memory for pointers it marks them as immovable, so any re-shuffling of memory caused by the large object being allocated the value passed to the function will point to the correct address to find out the final location in memory to update.
Any particular types of HANDLEs (hWnd, FILE, etc) are domain specific and point to a certain type of structure to protect against memory corruption.
based on accepted answer
$output = some_function();
echo $output;
if it results array then use json_encode it will result json array which is supportable by javascript
$output = some_function();
echo json_encode($output);
If someone wants to stop execution after you echo some result use exit method of php. It will work like return keyword
$output = some_function();
echo $output;
exit;
os.makedirs
is what you need. For chmod
or chown
you'll have to use os.walk
and use it on every file/dir yourself.
export user="your_new_owner"
export dbname="your_db_name"
cat <<EOF | docker run -i --rm --link postgres:postgres postgres sh -c "psql -h \$POSTGRES_PORT_5432_TCP_ADDR -p \$POSTGRES_PORT_5432_TCP_PORT -U postgres -d $dbname" | grep ALTER | docker run -i --rm --link postgres:postgres postgres sh -c "psql -h \$POSTGRES_PORT_5432_TCP_ADDR -p \$POSTGRES_PORT_5432_TCP_PORT -U postgres -d $dbname"
SELECT 'ALTER TABLE '||schemaname||'.'||tablename||' OWNER TO $user;' FROM pg_tables WHERE schemaname = 'public';
SELECT 'ALTER SEQUENCE '||relname||' OWNER TO $user;' FROM pg_class WHERE relkind = 'S';
EOF
You can also Try this:
var results= persons.GroupBy(n => new { n.PersonId, n.car})
.Select(g => new {
g.Key.PersonId,
g.Key.car)}).ToList();
This is my solution:
Request.Url.AbsoluteUri.Replace(Request.Url.Query, String.Empty);
Parse int is the tool you should use here, but like any tool it should be used correctly. When using parseInt you should always use the radix parameter to ensure the correct base is used
var currentValue = parseInt($("#replies").text(),10);
Simply use
$(document).height() // - $('body').offset().top
and / or
$(window).height()
instead of $('body').height();
Though I've spotted some nice answers relying on data binding, I didn't see any going to the full extent with that approach -- in the sense of enabling fragment resolution while allowing for fragment-free layout definitions in XML's.
So assuming data binding is enabled, here's a generic solution I can propose; A bit long but it definitely works (with some caveats):
This will run a fragment-aware search through contexts associated with the tapped-on view (e.g. button):
// CustomOnClick.kt
@file:JvmName("CustomOnClick")
package com.example
import android.app.Activity
import android.content.Context
import android.content.ContextWrapper
import android.view.View
import androidx.fragment.app.Fragment
import androidx.fragment.app.FragmentActivity
import java.lang.reflect.Method
fun onClick(view: View, methodName: String) {
resolveOnClickInvocation(view, methodName)?.invoke(view)
}
private data class OnClickInvocation(val obj: Any, val method: Method) {
fun invoke(view: View) {
method.invoke(obj, view)
}
}
private fun resolveOnClickInvocation(view: View, methodName: String): OnClickInvocation? =
searchContexts(view) { context ->
var invocation: OnClickInvocation? = null
if (context is Activity) {
val activity = context as? FragmentActivity
?: throw IllegalStateException("A non-FragmentActivity is not supported (looking up an onClick handler of $view)")
invocation = getTopFragment(activity)?.let { fragment ->
resolveInvocation(fragment, methodName)
}?: resolveInvocation(context, methodName)
}
invocation
}
private fun getTopFragment(activity: FragmentActivity): Fragment? {
val fragments = activity.supportFragmentManager.fragments
return if (fragments.isEmpty()) null else fragments.last()
}
private fun resolveInvocation(target: Any, methodName: String): OnClickInvocation? =
try {
val method = target.javaClass.getMethod(methodName, View::class.java)
OnClickInvocation(target, method)
} catch (e: NoSuchMethodException) {
null
}
private fun <T: Any> searchContexts(view: View, matcher: (context: Context) -> T?): T? {
var context = view.context
while (context != null && context is ContextWrapper) {
val result = matcher(context)
if (result == null) {
context = context.baseContext
} else {
return result
}
}
return null
}
Note: loosely based on the original Android implementation (see https://android.googlesource.com/platform/frameworks/base/+/a175a5b/core/java/android/view/View.java#3025)
Then, in data-binding aware XML's:
<layout>
<data>
<import type="com.example.CustomOnClick"/>
</data>
<Button
android:onClick='@{(v) -> CustomOnClick.onClick(v, "myClickMethod")}'
</Button>
</layout>
FragmentActivity
based implementationWikipedia, of all places, actually discusses this.
The idea is to make sure all package names are unique world-wide, by having authors use a variant of a DNS name they own to name the package. For example, the owners of the domain name joda.org
created a number of packages whose names begin with org.joda
, for example:
org.joda.time
org.joda.time.base
org.joda.time.chrono
org.joda.time.convert
org.joda.time.field
org.joda.time.format
First create a DataGridTemplateColumn
to contain the button:
<DataGridTemplateColumn>
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<Button Click="ShowHideDetails">Details</Button>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
When the button is clicked, update the containing DataGridRow
's DetailsVisibility
:
void ShowHideDetails(object sender, RoutedEventArgs e)
{
for (var vis = sender as Visual; vis != null; vis = VisualTreeHelper.GetParent(vis) as Visual)
if (vis is DataGridRow)
{
var row = (DataGridRow)vis;
row.DetailsVisibility =
row.DetailsVisibility == Visibility.Visible ? Visibility.Collapsed : Visibility.Visible;
break;
}
}
I ran into this recently and running the following fixed all the problems
mvn -fae install
Drop all default contstraints in a database - safe for nvarchar(max) threshold.
/* WARNING: THE SAMPLE BELOW; DROPS ALL THE DEFAULT CONSTRAINTS IN A DATABASE */
/* MAY 03, 2013 - BY WISEROOT */
declare @table_name nvarchar(128)
declare @column_name nvarchar(128)
declare @df_name nvarchar(128)
declare @cmd nvarchar(128)
declare table_names cursor for
SELECT t.name TableName, c.name ColumnName
FROM sys.columns c INNER JOIN
sys.tables t ON c.object_id = t.object_id INNER JOIN
sys.schemas s ON t.schema_id = s.schema_id
ORDER BY T.name, c.name
open table_names
fetch next from table_names into @table_name , @column_name
while @@fetch_status = 0
BEGIN
if exists (SELECT top(1) d.name from sys.tables t join sys.default_constraints d on d.parent_object_id = t.object_id join sys.columns c on c.object_id = t.object_id and c.column_id = d.parent_column_id where t.name = @table_name and c.name = @column_name)
BEGIN
SET @df_name = (SELECT top(1) d.name from sys.tables t join sys.default_constraints d on d.parent_object_id = t.object_id join sys.columns c on c.object_id = t.object_id and c.column_id = d.parent_column_id where t.name = @table_name and c.name = @column_name)
select @cmd = 'ALTER TABLE [' + @table_name + '] DROP CONSTRAINT [' + @df_name + ']'
print @cmd
EXEC sp_executeSQL @cmd;
END
fetch next from table_names into @table_name , @column_name
END
close table_names
deallocate table_names
simply provide the init block for HomeCell class
it's work in my case
This happened to me when I installed Intellij IDEA 2017, go to menu Preferences -> Build, Execution, Deployment -> Debugger and disable the option: "Force Classic VM for JDK 1.3.x and earlier". This works to me.
I have created an action in the Accounts
controller that calls a function to create the roles and assign the Admin
role to the default user. (You should probably remove the default user in production):
private async Task CreateRolesandUsers()
{
bool x = await _roleManager.RoleExistsAsync("Admin");
if (!x)
{
// first we create Admin rool
var role = new IdentityRole();
role.Name = "Admin";
await _roleManager.CreateAsync(role);
//Here we create a Admin super user who will maintain the website
var user = new ApplicationUser();
user.UserName = "default";
user.Email = "[email protected]";
string userPWD = "somepassword";
IdentityResult chkUser = await _userManager.CreateAsync(user, userPWD);
//Add default User to Role Admin
if (chkUser.Succeeded)
{
var result1 = await _userManager.AddToRoleAsync(user, "Admin");
}
}
// creating Creating Manager role
x = await _roleManager.RoleExistsAsync("Manager");
if (!x)
{
var role = new IdentityRole();
role.Name = "Manager";
await _roleManager.CreateAsync(role);
}
// creating Creating Employee role
x = await _roleManager.RoleExistsAsync("Employee");
if (!x)
{
var role = new IdentityRole();
role.Name = "Employee";
await _roleManager.CreateAsync(role);
}
}
After you could create a controller to manage roles for the users.
There are a few different ways you can achieve what you are asking for.
1.) Extend the application class and instantiate your controller and model objects there.
public class FavoriteColorsApplication extends Application {
private static FavoriteColorsApplication application;
private FavoriteColorsService service;
public FavoriteColorsApplication getInstance() {
return application;
}
@Override
public void onCreate() {
super.onCreate();
application = this;
application.initialize();
}
private void initialize() {
service = new FavoriteColorsService();
}
public FavoriteColorsService getService() {
return service;
}
}
Then you can call the your singleton from your custom Application object at any time:
public class FavoriteColorsActivity extends Activity {
private FavoriteColorsService service = null;
private ArrayAdapter<String> adapter;
private List<String> favoriteColors = new ArrayList<String>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_favorite_colors);
service = ((FavoriteColorsApplication) getApplication()).getService();
favoriteColors = service.findAllColors();
ListView lv = (ListView) findViewById(R.id.favoriteColorsListView);
adapter = new ArrayAdapter<String>(this, R.layout.favorite_colors_list_item,
favoriteColors);
lv.setAdapter(adapter);
}
2.) You can have your controller just create a singleton instance of itself:
public class Controller {
private static final String TAG = "Controller";
private static sController sController;
private Dao mDao;
private Controller() {
mDao = new Dao();
}
public static Controller create() {
if (sController == null) {
sController = new Controller();
}
return sController;
}
}
Then you can just call the create method from any Activity or Fragment and it will create a new controller if one doesn't already exist, otherwise it will return the preexisting controller.
3.) Finally, there is a slick framework created at Square which provides you dependency injection within Android. It is called Dagger. I won't go into how to use it here, but it is very slick if you need that sort of thing.
I hope I gave enough detail in regards to how you can do what you are hoping for.
An alternative solution to using the <ripple>
tag (which I personally prefer not to do, because the colors are not "default"), is the following:
Create a drawable for the button background, and include <item android:drawable="?attr/selectableItemBackground">
in the <layer-list>
Then (and I think this is the important part) programmatically set backgroundResource(R.drawable.custom_button)
on your button instance.
Button btn_temp = view.findViewById(R.id.btn_temp);
btn_temp.setBackgroundResource(R.drawable.custom_button);
<Button
android:id="@+id/btn_temp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/custom_button"
android:text="Test" />
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<shape android:shape="rectangle">
<solid android:color="@android:color/white" />
<corners android:radius="10dp" />
</shape>
</item>
<item android:drawable="?attr/selectableItemBackground" />
</layer-list>
If you want convert Keys:
List<string> listNumber = dicNumber.Keys.ToList();
else if you want convert Values:
List<string> listNumber = dicNumber.Values.ToList();
One more alternative cross-platform solution on powershell 6.2.3:
$headers = @{
'Authorization' = 'Token 12d119ad48f9b70ed53846f9e3d051dc31afab27'
}
$body = @"
{
"value":"3.92.0",
"product":"847"
}
"@
$params = @{
Uri = 'http://local.vcs:9999/api/v1/version/'
Headers = $headers
Method = 'POST'
Body = $body
ContentType = 'application/json'
}
Invoke-RestMethod @params
Using Android Studio 2.2.1, I clicked the Sync Project with Gradle Files option, from the dropdown at the top, Tools>Android
Similar, to an answer posted above, see below for a screenshot of how to get to this option.
You will have to annotate your service with @Service
since you have said I am using annotations for mapping
It's old but thought I'd add my two cents... Not sure if it will work but try using a KeyValuePair:
List<KeyValuePair<?, ?>> LinkList = new List<KeyValuePair<?, ?>>();
LinkList.Add(new KeyValuePair<?, ?>(Object, Object));
You'll end up with something like this:
LinkList[0] = <Object, Object>
LinkList[1] = <Object, Object>
LinkList[2] = <Object, Object>
and so on...
This is working fine, try out this.
var ob = $("#myListBox");
for (var i = 0; i < buildings.length; i++) {
var val = buildings[i];
var text = buildings[i];
ob.prepend("<option value="+ val +">" + text + "</option>");
}
Robocopy can be downloaded here for systems where it is not installed already. (I.e. Windows Server 2003.)
http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=17657 (no reboot required for installation)
Remember to set your path to the robocopy exe. You do this by right clicking "my computer"> properties>advanced>"Environment Variables", then find the path system variable and add this to the end: ";C:\Program Files\Windows Resource Kits\Tools" or wherever you installed it. Make sure to leave the path variable strings that are already there and just append the addtional path.
once the path is set, you can run the command that belisarius suggests. It works great.
Extension IDs can be found in:
chrome://extensions
(Chrome_Hotdog >> More_tools >> Extensions) Developer mode.
For Linux: $HOME/.config/google-chrome/Default/Preferences
(json file) under ["extensions"]
.
# or even faster copy paste answer if you have sudo on the host
sudo su - postgres -c "psql template1 -c 'CREATE EXTENSION IF NOT EXISTS \"dblink\";'"
In a relational database system, there can be only three types of table relationships:
So, a one-to-many
table relationship looks as follows:
Note that the relationship is based on the Foreign Key column (e.g., post_id
) in the child table.
So, there is a single source of truth when it comes to managing a one-to-many
table relationship.
Now, if you take a bidirectional entity relationship that maps on the one-to-many
table relationship we saw previously:
If you take a look at the diagram above, you can see that there are two ways to manage this relationship.
In the Post
entity, you have the comments
collection:
@OneToMany(
mappedBy = "post",
cascade = CascadeType.ALL,
orphanRemoval = true
)
private List<PostComment> comments = new ArrayList<>();
And, in the PostComment
, the post
association is mapped as follows:
@ManyToOne(
fetch = FetchType.LAZY
)
@JoinColumn(name = "post_id")
private Post post;
So, you have two sides that can change the entity association:
comments
child collection, a new post_comment
row should be associated with the parent post
entity via its post_id
column.post
property of the PostComment
entity, the post_id
column should be updated as well.Because there are two ways to represent the Foreign Key column, you must define which is the source of truth when it comes to translating the association state change into its equivalent Foreign Key column value modification.
The mappedBy
attribute tells that the @ManyToOne
side is in charge of managing the Foreign Key column, and the collection is used only to fetch the child entities and to cascade parent entity state changes to children (e.g., removing the parent should also remove the child entities).
It's called the inverse side because it references the child entity property that manages this table relationship.
Now, even if you defined the mappedBy
attribute and the child-side @ManyToOne
association manages the Foreign Key column, you still need to synchronize both sides of the bidirectional association.
The best way to do that is to add these two utility methods:
public void addComment(PostComment comment) {
comments.add(comment);
comment.setPost(this);
}
public void removeComment(PostComment comment) {
comments.remove(comment);
comment.setPost(null);
}
The addComment
and removeComment
methods ensure that both sides are synchronized. So, if we add a child entity, the child entity needs to point to the parent and the parent entity should have the child contained in the child collection.
pg_hba.conf
entry define login methods by IP addresses. You need to show the relevant portion of pg_hba.conf
in order to get proper help.
Change this line:
host all all <my-ip-address>/32 md5
To reflect your local network settings. So, if your IP is 192.168.16.78
(class C) with a mask of 255.255.255.0
, then put this:
host all all 192.168.16.0/24 md5
Make sure your WINDOWS MACHINE is in that network 192.168.16.0
and try again.
$timestamp='2014-11-21 16:38:00';
list($date,$time)=explode(' ',$timestamp);
// just time
preg_match("/ (\d\d:\d\d):\d\d$/",$timestamp,$match);
echo "\n<br>".$match[1];
Raw string literals:
>>> r'abc\dev\t'
'abc\\dev\\t'
The simplest way to achieve this is given below,
I)
Glide.with(context.getApplicationContext())
.load(Your Path)
.override(15, 15) // (change according to your wish)
.error(R.drawable.placeholder)
.into(image.score);
else you can follow the code below..
II)
1.Create a class.(Code is given below)
public class BlurTransformation extends BitmapTransformation {
private RenderScript rs;
public BlurTransformation(Context context) {
super( context );
rs = RenderScript.create( context );
}
@Override
protected Bitmap transform(BitmapPool pool, Bitmap toTransform, int outWidth, int outHeight) {
Bitmap blurredBitmap = toTransform.copy( Bitmap.Config.ARGB_8888, true );
// Allocate memory for Renderscript to work with
Allocation input = Allocation.createFromBitmap(
rs,
blurredBitmap,
Allocation.MipmapControl.MIPMAP_FULL,
Allocation.USAGE_SHARED
);
Allocation output = Allocation.createTyped(rs, input.getType());
// Load up an instance of the specific script that we want to use.
ScriptIntrinsicBlur script = ScriptIntrinsicBlur.create(rs, Element.U8_4(rs));
script.setInput(input);
// Set the blur radius
script.setRadius(10);
// Start the ScriptIntrinisicBlur
script.forEach(output);
// Copy the output to the blurred bitmap
output.copyTo(blurredBitmap);
toTransform.recycle();
return blurredBitmap;
}
@Override
public String getId() {
return "blur";
}
}
2.Set image to ImageView using Glide.
eg:
Glide.with(this)
.load(expertViewDetailsModel.expert.image)
.asBitmap()
.transform(new BlurTransformation(this))
.into(ivBackground);
Look into the MemoryStream
class.
Try this one
textBox1.Text = "Line1" + Environment.NewLine + "Line2";
Working fine for me...
Use beforeSend
:
$.ajax({
url: "http://localhost/PlatformPortal/Buyers/Account/SignIn",
data: { signature: authHeader },
type: "GET",
beforeSend: function(xhr){xhr.setRequestHeader('X-Test-Header', 'test-value');},
success: function() { alert('Success!' + authHeader); }
});
http://api.jquery.com/jQuery.ajax/
http://www.w3.org/TR/XMLHttpRequest/#the-setrequestheader-method
You can set the z-index in css
<div style="z-index: -1"></div>
I believe you can use the append
method
bigdata = data1.append(data2, ignore_index=True)
to keep their indexes just dont use the ignore_index
keyword ...
Use re.findall
or re.finditer
instead.
re.findall(pattern, string)
returns a list of matching strings.
re.finditer(pattern, string)
returns an iterator over MatchObject
objects.
Example:
re.findall( r'all (.*?) are', 'all cats are smarter than dogs, all dogs are dumber than cats')
# Output: ['cats', 'dogs']
[x.group() for x in re.finditer( r'all (.*?) are', 'all cats are smarter than dogs, all dogs are dumber than cats')]
# Output: ['all cats are', 'all dogs are']
as @JAC pointed out in the comments of the highest rated answer, the generic solution (for all numpy types) can be found in the thread Converting numpy dtypes to native python types.
Nevertheless, I´ll add my version of the solution below, as my in my case I needed a generic solution that combines these answers and with the answers of the other thread. This should work with almost all numpy types.
def convert(o):
if isinstance(o, np.generic): return o.item()
raise TypeError
json.dumps({'value': numpy.int64(42)}, default=convert)
You can use html
instead of text
and replace each occurrence of \n
with <br>
. You will have to correctly escape your text though.
x = x.replace(/&/g, '&')
.replace(/>/g, '>')
.replace(/</g, '<')
.replace(/\n/g, '<br>');
A URL of the form https://github.com/<owner>/<project>/commit/<hash>
will show you the changes introduced in that commit. For example here's a recent bugfix I made to one of my projects on GitHub:
https://github.com/jerith666/git-graph/commit/35e32b6a00dec02ae7d7c45c6b7106779a124685
You can also shorten the hash to any unique prefix, like so:
https://github.com/jerith666/git-graph/commit/35e32b
I know you just asked about GitHub, but for completeness: If you have the repository checked out, from the command line, you can achieve basically the same thing with either of these commands (unique prefixes work here too):
git show 35e32b6a00dec02ae7d7c45c6b7106779a124685
git log -p -1 35e32b6a00dec02ae7d7c45c6b7106779a124685
Note: If you shorten the commit hash too far, the command line gives you a helpful disambiguation message, but GitHub will just return a 404.
You can remove public keyword from your functions, because, you have to define a class in order to declare public, private or protected function
Best File Upload Using Jquery Ajax With Materialise Click Here to Download
When you select image the image will be Converted in base 64 and you can store this in to database so it will be light weight also.
I faced the same issue but my ViewPager was inside a TopFragment which created and set an adapter using setAdapter(new FragmentPagerAdapter(getChildFragmentManager()))
.
I fixed this issue by overriding onAttachFragment(Fragment childFragment)
in the TopFragment like this:
@Override
public void onAttachFragment(Fragment childFragment) {
if (childFragment instanceof OnboardingDiamondsFragment) {
mChildFragment = (ChildFragment) childFragment;
}
super.onAttachFragment(childFragment);
}
As known already (see answers above), when the childFragmentManager recreate itself, it also create the fragments which were inside the viewPager.
The important part is that after that, he calls onAttachFragment and now we have a reference to the new recreated fragment!
Hope this will help anyone getting this old Q like me :)
try this one.
export function printSectionOfWebpage(sectionSelector) {
const $body = jquery('body');
const $sectionToPrint = jquery(sectionSelector);
const $sectionToPrintParent = $sectionToPrint.parent();
const $printContainer = jquery('<div style="position:relative;">');
$printContainer.height($sectionToPrint.height()).append($sectionToPrint).prependTo($body);
const $content = $body.children().not($printContainer).not('script').detach();
/**
* Needed for those who use Bootstrap 3.x, because some of
* its `@media print` styles ain't play nicely when printing.
*/
const $patchedStyle = jquery('<style media="print">')
.text(
`
img { max-width: none !important; }
a[href]:after { content: ""; }
`
)
.appendTo('head');
window.print();
$body.prepend($content);
$sectionToPrintParent.prepend($sectionToPrint);
$printContainer.remove();
$patchedStyle.remove();
}
Java Usage example: myMenuItem.setIcon(android.R.drawable.ic_menu_save);
Resource Usage example: android:icon="@android:drawable/ic_menu_save"
Why reinvent the wheel? RandomStringUtils from Apache Commons has functions to which you can specify the character set from which characters are generated. You can take what you need to your app:
http://kickjava.com/src/org/apache/commons/lang/RandomStringUtils.java.htm
I had the same problem I used the solution offered above - I dropped the SYNONYM, created a VIEW with the same name as the synonym. it had a select using the dblink , and gave GRANT SELECT to the other schema It worked great.
The easiest thing to do is to set the content type of your ajax request to "application/json; charset=utf-8"
and then let your API method consume JSON. Like this:
var basicInfo = JSON.stringify({
firstName: playerProfile.firstName(),
lastName: playerProfile.lastName(),
gender: playerProfile.gender(),
address: playerProfile.address(),
country: playerProfile.country(),
bio: playerProfile.bio()
});
$.ajax({
url: "http://localhost:8080/social/profile/update",
type: 'POST',
dataType: 'json',
contentType: "application/json; charset=utf-8",
data: basicInfo,
success: function(data) {
// ...
}
});
@RequestMapping(
value = "/profile/update",
method = RequestMethod.POST,
produces = MediaType.APPLICATION_JSON_VALUE,
consumes = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity<ResponseModel> UpdateUserProfile(
@RequestBody User usersNewDetails,
HttpServletRequest request,
HttpServletResponse response
) {
// ...
}
I guess the problem is that Spring Boot has issues submitting form data which is not JSON via ajax request.
Note: the default content type for ajax is "application/x-www-form-urlencoded"
.
In Tomcat 8.0.44 I did this: create the JNDI on Tomcat's server.xml between the tag "GlobalNamingResources" For example:
<GlobalNamingResources>_x000D_
<!-- Editable user database that can also be used by_x000D_
UserDatabaseRealm to authenticate users_x000D_
-->_x000D_
<!-- Other previus resouces -->_x000D_
<Resource auth="Container" driverClassName="org.postgresql.Driver" global="jdbc/your_jndi" _x000D_
maxActive="100" maxIdle="20" maxWait="1000" minIdle="5" name="jdbc/your_jndi" password="your_password" _x000D_
type="javax.sql.DataSource" url="jdbc:postgresql://localhost:5432/your_database?user=postgres" username="database_username"/>_x000D_
</GlobalNamingResources>
_x000D_
<?xml version="1.0" encoding="UTF-8"?>_x000D_
<Context reloadable="true" >_x000D_
<ResourceLink name="jdbc/your_jndi"_x000D_
global="jdbc/your_jndi"_x000D_
auth="Container"_x000D_
type="javax.sql.DataSource" />_x000D_
</Context>
_x000D_
So if you're using Hiberte with spring you can tell to him to use the JNDI in your persistence.xml
<?xml version="1.0" encoding="UTF-8"?>_x000D_
<persistence xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"_x000D_
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"_x000D_
version="2.0" xmlns="http://java.sun.com/xml/ns/persistence">_x000D_
<persistence-unit name="UNIT_NAME" transaction-type="RESOURCE_LOCAL">_x000D_
<provider>org.hibernate.ejb.HibernatePersistence</provider>_x000D_
_x000D_
<properties>_x000D_
<property name="javax.persistence.jdbc.driver" value="org.postgresql.Driver" />_x000D_
<property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQL82Dialect" />_x000D_
_x000D_
<!-- <property name="hibernate.jdbc.time_zone" value="UTC"/>-->_x000D_
<property name="hibernate.hbm2ddl.auto" value="update" />_x000D_
<property name="hibernate.show_sql" value="false" />_x000D_
<property name="hibernate.format_sql" value="true"/> _x000D_
</properties>_x000D_
</persistence-unit>_x000D_
</persistence>
_x000D_
So in your spring.xml you can do that:
<bean id="postGresDataSource" class="org.springframework.jndi.JndiObjectFactoryBean">_x000D_
<property name="jndiName" value="java:comp/env/jdbc/your_jndi" />_x000D_
</bean>_x000D_
_x000D_
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">_x000D_
<property name="persistenceUnitName" value="UNIT_NAME" />_x000D_
<property name="dataSource" ref="postGresDataSource" />_x000D_
<property name="jpaVendorAdapter"> _x000D_
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />_x000D_
</property>_x000D_
</bean>
_x000D_
<property name="jndiName" value="java:comp/env/jdbc/your_jndi" />
_x000D_
In this example I used spring with xml but you can do this programmaticaly if you prefer.
That's it, I hope helped.
Image img = Image.FromFile(System.IO.Path.GetFullPath("C:\\ File Address"));
you need getfullpath by pointed class. I had same error and fixed...
For Redhat Linux 8 try this:
sudo yum install libncurses*
return
only makes sense inside a function. There is no function in your code.
Also, your code is worthy if the Department of Redundancy Department. Assuming you move it to a proper function, this would be better:
return confirm(".json_encode($message).");
EDIT much much later: Changed code to use json_encode
to ensure the message contents don't break just because of an apostrophe in the message.