An Iterator
moves forward only, if it read it once, it's done. Your
m.get(itr2.next());
is reading the next value of itr2.next();
, that is why you are missing a few (actually not a few, every other) keys.
Use a thin wrapper: HMap
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
public class HMap<K, V> {
private final Map<K, Map<K, V>> map;
public HMap() {
map = new HashMap<K, Map<K, V>>();
}
public HMap(final int initialCapacity) {
map = new HashMap<K, Map<K, V>>(initialCapacity);
}
public boolean containsKey(final Object key) {
return map.containsKey(key);
}
public V get(final Object key) {
final Map<K, V> entry = map.get(key);
if (entry != null)
return entry.values().iterator().next();
return null;
}
public K getKey(final Object key) {
final Map<K, V> entry = map.get(key);
if (entry != null)
return entry.keySet().iterator().next();
return null;
}
public V put(final K key, final V value) {
final Map<K, V> entry = map
.put(key, Collections.singletonMap(key, value));
if (entry != null)
return entry.values().iterator().next();
return null;
}
}
public void dumpMe(Map m) { dumpMe(m, ""); }
private void dumpMe(Map m, String padding)
{
Set s = m.keySet();
java.util.Iterator ir = s.iterator();
while (ir.hasNext())
{
String key = (String) ir.next();
AttributeValue value = (AttributeValue)m.get(key);
if (value == null)
continue;
if (value.getM() != null)
{
System.out.println (padding + key + " = {");
dumpMe((Map)value, padding + " ");
System.out.println(padding + "}");
}
else if (value.getS() != null ||
value.getN() != null )
{
System.out.println(padding + key + " = " + value.toString());
}
else
{
System.out.println(padding + key + " = UNKNOWN OBJECT: " + value.toString());
// You could also throw an exception here
}
} // while
}
//This code worked for me.
Its a good programming practice to avoid having null
values in a Map.
If you have an entry with null
value, then it is not possible to tell whether an entry is present in the map or has a null
value associated with it.
You can either define a constant for such cases (Example: String NOT_VALID = "#NA"
), or you can have another collection storing keys which have null
values.
Please check this link for more details.
When you create your own key pair object, you should face a few thing.
First, you should be aware of implementing hashCode()
and equals()
. You will need to do this.
Second, when implementing hashCode()
, make sure you understand how it works. The given user example
public int hashCode() {
return this.x ^ this.y;
}
is actually one of the worst implementations you can do. The reason is simple: you have a lot of equal hashes! And the hashCode()
should return int values that tend to be rare, unique at it's best. Use something like this:
public int hashCode() {
return (X << 16) + Y;
}
This is fast and returns unique hashes for keys between -2^16 and 2^16-1 (-65536 to 65535). This fits in almost any case. Very rarely you are out of this bounds.
Third, when implementing equals()
also know what it is used for and be aware of how you create your keys, since they are objects. Often you do unnecessary if statements cause you will always have the same result.
If you create keys like this: map.put(new Key(x,y),V);
you will never compare the references of your keys. Cause everytime you want to acces the map, you will do something like map.get(new Key(x,y));
. Therefore your equals()
does not need a statement like if (this == obj)
. It will never occure.
Instead of if (getClass() != obj.getClass())
in your equals()
better use if (!(obj instanceof this))
. It will be valid even for subclasses.
So the only thing you need to compare is actually X and Y. So the best equals()
implementation in this case would be:
public boolean equals (final Object O) {
if (!(O instanceof Key)) return false;
if (((Key) O).X != X) return false;
if (((Key) O).Y != Y) return false;
return true;
}
So in the end your key class is like this:
public class Key {
public final int X;
public final int Y;
public Key(final int X, final int Y) {
this.X = X;
this.Y = Y;
}
public boolean equals (final Object O) {
if (!(O instanceof Key)) return false;
if (((Key) O).X != X) return false;
if (((Key) O).Y != Y) return false;
return true;
}
public int hashCode() {
return (X << 16) + Y;
}
}
You can give your dimension indices X
and Y
a public access level, due to the fact they are final and do not contain sensitive information. I'm not a 100% sure whether private
access level works correctly in any case when casting the Object
to a Key
.
If you wonder about the finals, I declare anything as final which value is set on instancing and never changes - and therefore is an object constant.
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);
}
I was running into the problem where i had the json with some common keys. I wanted to group all the values having the same key. After some surfing I found hashmap package. Which is really helpful.
To group the element with the same key, I used multi(key:*, value:*, key2:*, value2:*, ...)
.
This package is somewhat similar to Java Hashmap collection, but not as powerful as Java Hashmap.
You're mistaken on point three. Two entries can have the same hash code but not be equal. Take a look at the implementation of HashMap.get from the OpenJdk. You can see that it checks that the hashes are equal and the keys are equal. Were point three true, then it would be unnecessary to check that the keys are equal. The hash code is compared before the key because the former is a more efficient comparison.
If you're interested in learning a little more about this, take a look at the Wikipedia article on Open Addressing collision resolution, which I believe is the mechanism that the OpenJdk implementation uses. That mechanism is subtly different than the "bucket" approach one of the other answers mentions.
HashMap operation is dependent factor of hashCode implementation. For the ideal scenario lets say the good hash implementation which provide unique hash code for every object (No hash collision) then the best, worst and average case scenario would be O(1). Let's consider a scenario where a bad implementation of hashCode always returns 1 or such hash which has hash collision. In this case the time complexity would be O(n).
Now coming to the second part of the question about memory, then yes memory constraint would be taken care by JVM.
Hash-Map stores the (key,value) pair as the Map.Entry Type.As you know that Hash-Map uses Linked Hash-Map(In case Collision occurs). Therefore each Node in the Bucket of Hash-Map is of Type Map.Entry. So whenever you iterate through the Hash-Map you will get Nodes of Type Map.Entry.
Now in your example when you are iterating through the Hash-Map, you will get Map.Entry Type(Which is Interface), To get the Key and Value from this Map.Entry Node Object, interface provided methods like getValue(), getKey() etc. So as per the code, In your Object you are adding all operators JButtons viz (+,-,/,*,=).
Map<String, String> map = new HashMap<String, String>();
map.put("key1", "value1");
map.put("key2", "value2");
Object[][] twoDarray = new Object[map.size()][2];
Object[] keys = map.keySet().toArray();
Object[] values = map.values().toArray();
for (int row = 0; row < twoDarray.length; row++) {
twoDarray[row][0] = keys[row];
twoDarray[row][1] = values[row];
}
// Print out the new 2D array
for (int i = 0; i < twoDarray.length; i++) {
for (int j = 0; j < twoDarray[i].length; j++) {
System.out.println(twoDarray[i][j]);
}
}
List<String> list = new ArrayList<String>();
Map<String, String> map = new HashMap<String, String>();
for (String str : map.keySet()) {
list.add(str);
}
Collections.sort(list);
for (String str : list) {
System.out.println(str);
}
The reason for using dictionaries in the first place is performance. Although it is correct that you can use named vectors and lists for the task the issue is that they are becoming quite slow and memory hungry with more data.
Yet what many people don't know is that R has indeed an inbuilt dictionary data structure: environments with the option hash = TRUE
See the following example for how to make it work:
# vectorize assign, get and exists for convenience
assign_hash <- Vectorize(assign, vectorize.args = c("x", "value"))
get_hash <- Vectorize(get, vectorize.args = "x")
exists_hash <- Vectorize(exists, vectorize.args = "x")
# keys and values
key<- c("tic", "tac", "toe")
value <- c(1, 22, 333)
# initialize hash
hash = new.env(hash = TRUE, parent = emptyenv(), size = 100L)
# assign values to keys
assign_hash(key, value, hash)
## tic tac toe
## 1 22 333
# get values for keys
get_hash(c("toe", "tic"), hash)
## toe tic
## 333 1
# alternatively:
mget(c("toe", "tic"), hash)
## $toe
## [1] 333
##
## $tic
## [1] 1
# show all keys
ls(hash)
## [1] "tac" "tic" "toe"
# show all keys with values
get_hash(ls(hash), hash)
## tac tic toe
## 22 1 333
# remove key-value pairs
rm(list = c("toe", "tic"), envir = hash)
get_hash(ls(hash), hash)
## tac
## 22
# check if keys are in hash
exists_hash(c("tac", "nothere"), hash)
## tac nothere
## TRUE FALSE
# for single keys this is also possible:
# show value for single key
hash[["tac"]]
## [1] 22
# create new key-value pair
hash[["test"]] <- 1234
get_hash(ls(hash), hash)
## tac test
## 22 1234
# update single value
hash[["test"]] <- 54321
get_hash(ls(hash), hash)
## tac test
## 22 54321
Edit: On the basis of this answer I wrote a blog post with some more context: http://blog.ephorie.de/hash-me-if-you-can
Use Java8 built in fuction 'computeIfPresent'
Example:
public class ExampleToUpdateMapValue {
public static void main(String[] args) {
Map<String,String> bookAuthors = new TreeMap<>();
bookAuthors.put("Genesis","Moses");
bookAuthors.put("Joshua","Joshua");
bookAuthors.put("Judges","Samuel");
System.out.println("---------------------Before----------------------");
bookAuthors.entrySet().stream().forEach(System.out::println);
// To update the existing value using Java 8
bookAuthors.computeIfPresent("Judges", (k,v) -> v = "Samuel/Nathan/Gad");
System.out.println("---------------------After----------------------");
bookAuthors.entrySet().stream().forEach(System.out::println);
}
}
Here's a simple example to demonstrate Map
usage:
Map<String, String> map = new HashMap<String, String>();
map.put("Color1","Red");
map.put("Color2","Blue");
map.put("Color3","Green");
map.put("Color4","White");
System.out.println(map);
// {Color4=White, Color3=Green, Color1=Red, Color2=Blue}
System.out.println(map.get("Color2")); // Blue
System.out.println(map.keySet());
// [Color4, Color3, Color1, Color2]
for (Map.Entry<String,String> entry : map.entrySet()) {
System.out.printf("%s -> %s%n", entry.getKey(), entry.getValue());
}
// Color4 -> White
// Color3 -> Green
// Color1 -> Red
// Color2 -> Blue
Note that the entries are iterated in arbitrary order. If you need a specific order, then you may consider e.g. LinkedHashMap
Map
interfaceOn iterating over entries:
Iterator
.On different Map
characteristics:
enum
You may want to consider using an enum
and EnumMap
instead of Map<String,String>
.
Dictionary is the most common, but you can use other types of collections, e.g. System.Collections.Generic.SynchronizedKeyedCollection, System.Collections.Hashtable, or any KeyValuePair collection
The C++ spec doesn't say exactly what algorithm you must use for the STL containers. It does, however, put certain constraints on their performance, which rules out the use of hash tables for map
and other associative containers. (They're most commonly implemented with red/black trees.) These constraints require better worst-case performance for these containers than hash tables can deliver.
Many people really do want hash tables, however, so hash-based STL associative containers have been a common extension for years. Consequently, they added unordered_map
and such to later versions of the C++ standard.
Update
Ruby 2.1.0 is released today. And I comes with Array#to_h
(release notes and ruby-doc), which solves the issue of converting an Array
to a Hash
.
Ruby docs example:
[[:foo, :bar], [1, 2]].to_h # => {:foo => :bar, 1 => 2}
Work 100% sure try this code for the get all hashmap key and value
static HashMap<String, String> map = new HashMap<>();
map.put("one" " a " );
map.put("two" " b " );
map.put("three" " c " );
map.put("four" " d " );
just call this method whenever you want to show the HashMap value
private void ShowHashMapValue() {
/**
* get the Set Of keys from HashMap
*/
Set setOfKeys = map.keySet();
/**
* get the Iterator instance from Set
*/
Iterator iterator = setOfKeys.iterator();
/**
* Loop the iterator until we reach the last element of the HashMap
*/
while (iterator.hasNext()) {
/**
* next() method returns the next key from Iterator instance.
* return type of next() method is Object so we need to do DownCasting to String
*/
String key = (String) iterator.next();
/**
* once we know the 'key', we can get the value from the HashMap
* by calling get() method
*/
String value = map.get(key);
System.out.println("Key: " + key + ", Value: " + value);
}
}
Rails has an except/except! method that returns the hash with those keys removed. If you're already using Rails, there's no sense in creating your own version of this.
class Hash
# Returns a hash that includes everything but the given keys.
# hash = { a: true, b: false, c: nil}
# hash.except(:c) # => { a: true, b: false}
# hash # => { a: true, b: false, c: nil}
#
# This is useful for limiting a set of parameters to everything but a few known toggles:
# @person.update(params[:person].except(:admin))
def except(*keys)
dup.except!(*keys)
end
# Replaces the hash without the given keys.
# hash = { a: true, b: false, c: nil}
# hash.except!(:c) # => { a: true, b: false}
# hash # => { a: true, b: false }
def except!(*keys)
keys.each { |key| delete(key) }
self
end
end
You may use Map.entrySet()
method:
for (Map.Entry entry : objectSet.entrySet())
{
System.out.println("key: " + entry.getKey() + "; value: " + entry.getValue());
}
You can manually iterate over the elements of the set:
Iterator<Integer> iterator = set.iterator();
while (iterator.hasNext()) {
Integer element = iterator.next();
if (element % 2 == 0) {
iterator.remove();
}
}
You will often see this pattern using a for
loop rather than a while
loop:
for (Iterator<Integer> i = set.iterator(); i.hasNext();) {
Integer element = i.next();
if (element % 2 == 0) {
i.remove();
}
}
As people have pointed out, using a for
loop is preferred because it keeps the iterator variable (i
in this case) confined to a smaller scope.
Generics can't use primitive types in the form of keywords.
Use
public HashMap<Character, Integer> buildMap(String letters)
{
HashMap<Character, Integer> checkSum = new HashMap<Character, Integer>();
for ( int i = 0; i < letters.length(); ++i )
{
checkSum.put(letters.charAt(i), primes[i]);
}
return checkSum;
}
Updated: With Java 7 and later, you can use the diamond operator.
HashMap<Character, Integer> checkSum = new HashMap<>();
HashMap and Hashtable both are used to store data in key and value form. Both are using hashing technique to store unique keys. ut there are many differences between HashMap and Hashtable classes that are given below.
streetno = { 1 : "Sachin Tendulkar",
2 : "Dravid",
3 : "Sehwag",
4 : "Laxman",
5 : "Kohli" }
And to retrieve values:
name = streetno.get(3, "default value")
Or
name = streetno[3]
That's using number as keys, put quotes around the numbers to use strings as keys.
A null key can also be helpful when the map stores data for UI selections where the map key represents a bean field.
A corresponding null field value would for example be represented as "(please select)" in the UI selection.
I always used:
HashMap<String, ArrayList<String>> hashy = new HashMap<String, ArrayList<String>>();
if I wanted to apply multiple things to one identifying key.
public void MultiHash(){
HashMap<String, ArrayList<String>> hashy = new HashMap<String, ArrayList<String>>();
String key = "Your key";
ArrayList<String> yourarraylist = hashy.get(key);
for(String valuessaved2key : yourarraylist){
System.out.println(valuessaved2key);
}
}
you could always do something like this and create yourself a maze!
public void LOOK_AT_ALL_THESE_HASHMAPS(){
HashMap<String, HashMap<String, HashMap<String, HashMap<String, String>>>> theultimatehashmap = new HashMap <String, HashMap<String, HashMap<String, HashMap<String, String>>>>();
String ballsdeep_into_the_hashmap = theultimatehashmap.get("firststring").get("secondstring").get("thirdstring").get("forthstring");
}
$fruits = array (
"fruits" => array("a" => "Orange", "b" => "Banana", "c" => "Apple"),
"numbers" => array(1, 2, 3, 4, 5, 6),
"holes" => array("first", 5 => "second", "third")
);
echo $fruits["fruits"]["b"]
outputs 'Banana'
The parallel collector will throw an OutOfMemoryError
if too much time is being spent in garbage collection. In particular, if more than 98% of the total time is spent in garbage collection and less than 2% of the heap is recovered, OutOfMemoryError
will be thrown. This feature is designed to prevent applications from running for an extended period of time while making little or no progress because the heap is too small. If necessary, this feature can be disabled by adding the option -XX:-UseGCOverheadLimit
to the command line.
You could use Gson library
Type type = new TypeToken<HashMap<String, String>>() {}.getType();
new Gson().fromJson(jsonString, type);
As an addition to e.g. @Intrepidd s answer, in certain situations you want to use fetch
instead of []
. For fetch
not to throw an exception when the key is not found, pass it a default value.
puts "ok" if hash.fetch('key', nil) == 'X'
Reference: https://docs.ruby-lang.org/en/2.3.0/Hash.html .
The amount of capacity which is to be exhausted for the HashMap to increase its capacity ?
Load factor is by default 0.75 of the initial capacity (16) therefore 25% of the buckets will be free before there is an increase in the capacity & this makes many new buckets with new hashcodes pointing to them to exist just after the increase in the number of buckets.
If you set the loading factor to say 1.0 then something very interesting might happen.
Say you are adding an object x to your hashmap whose hashCode is 888 & in your hashmap the bucket representing the hashcode is free , so the object x gets added to the bucket, but now again say if you are adding another object y whose hashCode is also 888 then your object y will get added for sure BUT at the end of the bucket (because the buckets are nothing but linkedList implementation storing key,value & next) now this has a performance impact ! Since your object y is no longer present in the head of the bucket if you perform a lookup the time taken is not going to be O(1) this time it depends on how many items are there in the same bucket. This is called hash collision by the way & this even happens when your loading factor is less than 1.
Lower load factor = more free buckets = less chances of collision = high performance = high space requirement.
Correct me if i am wrong somewhere.
Use Dictionary - it uses hashtable but is typesafe.
Also, your Java code for
int a = map.get(key);
//continue with your logic
will be best coded in C# this way:
int a;
if(dict.TryGetValue(key, out a)){
//continue with your logic
}
This way, you can scope the need of variable "a" inside a block and it is still accessible outside the block if you need it later.
To answer your question in one sentence:
Per default, Maps don't have a last entry, it's not part of their contract.
And a side note: it's good practice to code against interfaces, not the implementation classes (see Effective Java by Joshua Bloch, Chapter 8, Item 52: Refer to objects by their interfaces).
So your declaration should read:
Map<String,Integer> map = new HashMap<String,Integer>();
(All maps share a common contract, so the client need not know what kind of map it is, unless he specifies a sub interface with an extended contract).
There is a sub interface SortedMap that extends the map interface with order-based lookup methods and it has a sub interface NavigableMap that extends it even further. The standard implementation of this interface, TreeMap, allows you to sort entries either by natural ordering (if they implement the Comparable interface) or by a supplied Comparator.
You can access the last entry through the lastEntry method:
NavigableMap<String,Integer> map = new TreeMap<String, Integer>();
// add some entries
Entry<String, Integer> lastEntry = map.lastEntry();
There is also the special case of LinkedHashMap, a HashMap implementation that stores the order in which keys are inserted. There is however no interface to back up this functionality, nor is there a direct way to access the last key. You can only do it through tricks such as using a List in between:
Map<String,String> map = new LinkedHashMap<String, Integer>();
// add some entries
List<Entry<String,Integer>> entryList =
new ArrayList<Map.Entry<String, Integer>>(map.entrySet());
Entry<String, Integer> lastEntry =
entryList.get(entryList.size()-1);
Since you don't control the insertion order, you should go with the NavigableMap interface, i.e. you would write a comparator that positions the Not-Specified
entry last.
Here is an example:
final NavigableMap<String,Integer> map =
new TreeMap<String, Integer>(new Comparator<String>() {
public int compare(final String o1, final String o2) {
int result;
if("Not-Specified".equals(o1)) {
result=1;
} else if("Not-Specified".equals(o2)) {
result=-1;
} else {
result =o1.compareTo(o2);
}
return result;
}
});
map.put("test", Integer.valueOf(2));
map.put("Not-Specified", Integer.valueOf(1));
map.put("testtest", Integer.valueOf(3));
final Entry<String, Integer> lastEntry = map.lastEntry();
System.out.println("Last key: "+lastEntry.getKey()
+ ", last value: "+lastEntry.getValue());
Output:
Last key: Not-Specified, last value: 1
If you must rely on HashMaps, there is still a solution, using a) a modified version of the above comparator, b) a List initialized with the Map's entrySet and c) the Collections.sort() helper method:
final Map<String, Integer> map = new HashMap<String, Integer>();
map.put("test", Integer.valueOf(2));
map.put("Not-Specified", Integer.valueOf(1));
map.put("testtest", Integer.valueOf(3));
final List<Entry<String, Integer>> entries =
new ArrayList<Entry<String, Integer>>(map.entrySet());
Collections.sort(entries, new Comparator<Entry<String, Integer>>(){
public int compareKeys(final String o1, final String o2){
int result;
if("Not-Specified".equals(o1)){
result = 1;
} else if("Not-Specified".equals(o2)){
result = -1;
} else{
result = o1.compareTo(o2);
}
return result;
}
@Override
public int compare(final Entry<String, Integer> o1,
final Entry<String, Integer> o2){
return this.compareKeys(o1.getKey(), o2.getKey());
}
});
final Entry<String, Integer> lastEntry =
entries.get(entries.size() - 1);
System.out.println("Last key: " + lastEntry.getKey() + ", last value: "
+ lastEntry.getValue());
}
Output:
Last key: Not-Specified, last value: 1
A simple one liner using Java-8
Key key = Collections.max(map.entrySet(), Map.Entry.comparingByValue()).getKey();
Yes, it is a hash mapping or hash table. You can read a description of python's dict implementation, as written by Tim Peters, here.
That's why you can't use something 'not hashable' as a dict key, like a list:
>>> a = {}
>>> b = ['some', 'list']
>>> hash(b)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: list objects are unhashable
>>> a[b] = 'some'
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: list objects are unhashable
You can read more about hash tables or check how it has been implemented in python and why it is implemented that way.
The simplest solution that I can think of is using Properties class.
Saving the map:
Map<String, String> ldapContent = new HashMap<String, String>();
Properties properties = new Properties();
for (Map.Entry<String,String> entry : ldapContent.entrySet()) {
properties.put(entry.getKey(), entry.getValue());
}
properties.store(new FileOutputStream("data.properties"), null);
Loading the map:
Map<String, String> ldapContent = new HashMap<String, String>();
Properties properties = new Properties();
properties.load(new FileInputStream("data.properties"));
for (String key : properties.stringPropertyNames()) {
ldapContent.put(key, properties.get(key).toString());
}
EDIT:
if your map contains plaintext values, they will be visible if you open file data via any text editor, which is not the case if you serialize the map:
ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream("data.ser"));
out.writeObject(ldapContent);
out.close();
EDIT2:
instead of for loop (as suggested by OldCurmudgeon) in saving example:
properties.putAll(ldapContent);
however, for the loading example this is the best that can be done:
ldapContent = new HashMap<Object, Object>(properties);
You may try to use Trove http://trove.starlight-systems.com/
TIntObjectHashMap is probably what you are looking for.
Use the keySet()
method to return a set with all the keys of a Map
.
If you want to keep your Map ordered you can use a TreeMap
.
The simplest solution would be to use a sorted map like TreeMap instead of HashMap. If you do not have control over the map construction, then the minimal solution would be to construct a sorted set of keys. You don't really need a new map.
Set<String> sortedKeys = new TreeSet<String>();
sortedKeys.addAll(codes.keySet());
for(String key: sortedKeys){
println(key + ":" + codes.get(key));
}
Simple solution :-
List<String> list = new ArrayList<String>(Arrays.asList("a", "b", "d", "c"));
List<String> list2 = new ArrayList<String>(Arrays.asList("b", "f", "c"));
list.retainAll(list2);
list2.removeAll(list);
System.out.println("similiar " + list);
System.out.println("different " + list2);
Output :-
similiar [b, c]
different [f]
I would suggest the following:
String[] parsedInput = str.split("\n"); String firstName = parsedInput[0].split(": ")[1]; String lastName = parsedInput[1].split(": ")[1]; myMap.put(firstName,lastName);
The current C++ standard does not have hash maps, but the coming C++0x standard does, and these are already supported by g++ in the shape of "unordered maps":
#include <unordered_map>
#include <iostream>
#include <string>
using namespace std;
int main() {
unordered_map <string, int> m;
m["foo"] = 42;
cout << m["foo"] << endl;
}
In order to get this compile, you need to tell g++ that you are using C++0x:
g++ -std=c++0x main.cpp
These maps work pretty much as std::map does, except that instead of providing a custom operator<()
for your own types, you need to provide a custom hash function - suitable functions are provided for types like integers and strings.
Well if you know the basics behind them, it shouldn't be too hard.
Generally you create an array called "buckets" that contain the key and value, with an optional pointer to create a linked list.
When you access the hash table with a key, you process the key with a custom hash function which will return an integer. You then take the modulus of the result and that is the location of your array index or "bucket". Then you check the unhashed key with the stored key, and if it matches, then you found the right place.
Otherwise, you've had a "collision" and must crawl through the linked list and compare keys until you match. (note some implementations use a binary tree instead of linked list for collisions).
Check out this fast hash table implementation:
If you will use Generics and define your map as
Map<String,String> map = new HashMap<String,String>();
then fetching value as
String s = map.get("keyStr");
you wont be required to typecast the map.get() or call toString method to get String value
You can use ECMAScript 6 WeakMap
or Map
:
WeakMaps are key/value maps in which keys are objects.
Map
objects are simple key/value maps. Any value (both objects and primitive values) may be used as either a key or a value.
Be aware that neither is widely supported, but you can use ECMAScript 6 Shim (requires native ECMAScript 5 or ECMAScript 5 Shim) to support Map
, but not WeakMap
(see why).
If all you are trying to do is get the value out of the hashmap itself, you can do something like the following:
for (Object key : map.keySet()) {
Object value = map.get(key);
//TODO: this
}
Or, you can iterate over the entries of a map, if that is what you are interested in:
for (Map.Entry<Object, Object> entry : map.entrySet()) {
Object key = entry.getKey();
Object value = entry.getValue();
//TODO: other cool stuff
}
As a community, we might be able to give you better/more appropriate answers if we had some idea why you needed the indexes or what you thought the indexes could do for you.
The standard library includes the ordered and the unordered map (std::map
and std::unordered_map
) containers. In an ordered map the elements are sorted by the key, insert and access is in O(log n). Usually the standard library internally uses red black trees for ordered maps. But this is just an implementation detail. In an unordered map insert and access is in O(1). It is just another name for a hashtable.
An example with (ordered) std::map
:
#include <map>
#include <iostream>
#include <cassert>
int main(int argc, char **argv)
{
std::map<std::string, int> m;
m["hello"] = 23;
// check if key is present
if (m.find("world") != m.end())
std::cout << "map contains key world!\n";
// retrieve
std::cout << m["hello"] << '\n';
std::map<std::string, int>::iterator i = m.find("hello");
assert(i != m.end());
std::cout << "Key: " << i->first << " Value: " << i->second << '\n';
return 0;
}
Output:
23 Key: hello Value: 23
If you need ordering in your container and are fine with the O(log n) runtime then just use std::map
.
Otherwise, if you really need a hash-table (O(1) insert/access), check out std::unordered_map
, which has a similar to std::map
API (e.g. in the above example you just have to search and replace map
with unordered_map
).
The unordered_map
container was introduced with the C++11 standard revision. Thus, depending on your compiler, you have to enable C++11 features (e.g. when using GCC 4.8 you have to add -std=c++11
to the CXXFLAGS).
Even before the C++11 release GCC supported unordered_map
- in the namespace std::tr1
. Thus, for old GCC compilers you can try to use it like this:
#include <tr1/unordered_map>
std::tr1::unordered_map<std::string, int> m;
It is also part of boost, i.e. you can use the corresponding boost-header for better portability.
Assuming you have:
HashMap<Key, Value> map; // Assigned or populated somehow.
For a list of values:
List<Value> values = new ArrayList<Value>(map.values());
For a list of keys:
List<Key> keys = new ArrayList<Key>(map.keySet());
Note that the order of the keys and values will be unreliable with a HashMap; use a LinkedHashMap if you need to preserve one-to-one correspondence of key and value positions in their respective lists.
Here's a short and sweet one liner if you only need to support simple ASCII key/value query strings:
hash = {"foo" => "bar", "fooz" => 123}
# => {"foo"=>"bar", "fooz"=>123}
query_string = hash.to_a.map { |x| "#{x[0]}=#{x[1]}" }.join("&")
# => "foo=bar&fooz=123"
Enumerator
includes Enumerable
. Since 2.1
, Enumerable
also has a method #to_h
. That's why, we can write :-
a = ["item 1", "item 2", "item 3", "item 4"]
a.each_slice(2).to_h
# => {"item 1"=>"item 2", "item 3"=>"item 4"}
Because #each_slice
without block gives us Enumerator
, and as per the above explanation, we can call the #to_h
method on the Enumerator
object.
All of the answers here now contain the old behavior of maps. In Go 1.12+, you can just print a map value and it will be sorted by key automatically. This has been added because it allows the testing of map values easily.
func main() {
m := map[int]int{3: 5, 2: 4, 1: 3}
fmt.Println(m)
// In Go 1.12+
// Output: map[1:3 2:4 3:5]
// Before Go 1.12 (the order was undefined)
// map[3:5 2:4 1:3]
}
Maps are now printed in key-sorted order to ease testing. The ordering rules are:
- When applicable, nil compares low
- ints, floats, and strings order by <
- NaN compares less than non-NaN floats
- bool compares false before true
- Complex compares real, then imaginary
- Pointers compare by machine address
- Channel values compare by machine address
- Structs compare each field in turn
- Arrays compare each element in turn
- Interface values compare first by reflect.Type describing the concrete type and then by concrete value as described in the previous rules.
When printing maps, non-reflexive key values like NaN were previously displayed as
<nil>
. As of this release, the correct values are printed.
Read more here.
First you need to define the List
as :
List<Map<String, ArrayList<String>>> list = new ArrayList<>();
To add the Map
to the List
, use add(E e) method :
list.add(map);
In your second example the "map" reference is of type Map
, which is an interface implemented by HashMap
(and other types of Map
). This interface is a contract saying that the object maps keys to values and supports various operations (e.g. put
, get
). It says nothing about the implementation of the Map
(in this case a HashMap
).
The second approach is generally preferred as you typically wouldn't want to expose the specific map implementation to methods using the Map
or via an API definition.
@ordered = {}
@unordered.keys.sort.each do |key|
@ordered[key] = @unordered[key]
end
HashMap
is unordered per the second line of the documentation:
This class makes no guarantees as to the order of the map; in particular, it does not guarantee that the order will remain constant over time.
Perhaps you can do as aix suggests and use a LinkedHashMap
, or another ordered collection. This link can help you find the most appropriate collection to use.
Here's a little method I wrote for exactly this purpose. It uses Validate from Apache Commons.
Feel free to use it.
/**
* Converts a <code>List</code> to a map. One of the methods of the list is called to retrive
* the value of the key to be used and the object itself from the list entry is used as the
* objct. An empty <code>Map</code> is returned upon null input.
* Reflection is used to retrieve the key from the object instance and method name passed in.
*
* @param <K> The type of the key to be used in the map
* @param <V> The type of value to be used in the map and the type of the elements in the
* collection
* @param coll The collection to be converted.
* @param keyType The class of key
* @param valueType The class of the value
* @param keyMethodName The method name to call on each instance in the collection to retrieve
* the key
* @return A map of key to value instances
* @throws IllegalArgumentException if any of the other paremeters are invalid.
*/
public static <K, V> Map<K, V> asMap(final java.util.Collection<V> coll,
final Class<K> keyType,
final Class<V> valueType,
final String keyMethodName) {
final HashMap<K, V> map = new HashMap<K, V>();
Method method = null;
if (isEmpty(coll)) return map;
notNull(keyType, Messages.getString(KEY_TYPE_NOT_NULL));
notNull(valueType, Messages.getString(VALUE_TYPE_NOT_NULL));
notEmpty(keyMethodName, Messages.getString(KEY_METHOD_NAME_NOT_NULL));
try {
// return the Method to invoke to get the key for the map
method = valueType.getMethod(keyMethodName);
}
catch (final NoSuchMethodException e) {
final String message =
String.format(
Messages.getString(METHOD_NOT_FOUND),
keyMethodName,
valueType);
e.fillInStackTrace();
logger.error(message, e);
throw new IllegalArgumentException(message, e);
}
try {
for (final V value : coll) {
Object object;
object = method.invoke(value);
@SuppressWarnings("unchecked")
final K key = (K) object;
map.put(key, value);
}
}
catch (final Exception e) {
final String message =
String.format(
Messages.getString(METHOD_CALL_FAILED),
method,
valueType);
e.fillInStackTrace();
logger.error(message, e);
throw new IllegalArgumentException(message, e);
}
return map;
}
Java 8 way of doing,
String firstKey = map.keySet().stream().findFirst().get();
class Gift
def initialize
@name = "book"
@price = 15.95
end
end
gift = Gift.new
hash = {}
gift.instance_variables.each {|var| hash[var.to_s.delete("@")] = gift.instance_variable_get(var) }
p hash # => {"name"=>"book", "price"=>15.95}
Alternatively with each_with_object
:
gift = Gift.new
hash = gift.instance_variables.each_with_object({}) { |var, hash| hash[var.to_s.delete("@")] = gift.instance_variable_get(var) }
p hash # => {"name"=>"book", "price"=>15.95}
for (Map.Entry<String, Tab> entry : hash.entrySet()) {
String key = entry.getKey();
Tab tab = entry.getValue();
// do something with key and/or tab
}
Works like a charm.
HashMaps don't allow access by position, it only knows about the hash code and and it can retrieve the value if it can calculate the hash code of the key. TreeMaps have a notion of ordering. Linkedhas maps preserve the order in which they entered the map.
If you're not restricted to JQuery, you can use the prototype.js framework. It has a class called Hash: You can even use JQuery & prototype.js together. Just type jQuery.noConflict();
var h = new Hash();
h.set("key", "value");
h.get("key");
h.keys(); // returns an array of keys
h.values(); // returns an array of values
In a HashMap
the key is an object, that contains hashCode()
and equals(Object)
methods.
When you insert a new entry into the Map, it checks whether the hashCode
is already known. Then, it will iterate through all objects with this hashcode, and test their equality with .equals()
. If an equal object is found, the new value replaces the old one. If not, it will create a new entry in the map.
Usually, talking about maps, you use collision when two objects have the same hashCode
but they are different. They are internally stored in a list.
Mark, this is already answered in your previous topic. But OK, here it is again:
Suppose ${list}
points to a List<Object>
, then the following
<c:forEach items="${list}" var="item">
${item}<br>
</c:forEach>
does basically the same as as following in "normal Java":
for (Object item : list) {
System.out.println(item);
}
If you have a List<Map<K, V>>
instead, then the following
<c:forEach items="${list}" var="map">
<c:forEach items="${map}" var="entry">
${entry.key}<br>
${entry.value}<br>
</c:forEach>
</c:forEach>
does basically the same as as following in "normal Java":
for (Map<K, V> map : list) {
for (Entry<K, V> entry : map.entrySet()) {
System.out.println(entry.getKey());
System.out.println(entry.getValue());
}
}
The key
and value
are here not special methods or so. They are actually getter methods of Map.Entry
object (click at the blue Map.Entry
link to see the API doc). In EL (Expression Language) you can use the .
dot operator to access getter methods using "property name" (the getter method name without the get
prefix), all just according the Javabean specification.
That said, you really need to cleanup the "answers" in your previous topic as they adds noise to the question. Also read the comments I posted in your "answers".
Java doesn't have associative arrays like PHP does.
There are various solutions for what you are doing, such as using a Map, but it depends on how you want to look up the information. You can easily write a class that holds all your information and store instances of them in an ArrayList
.
public class Foo{
public String name, fname;
public Foo(String name, String fname){
this.name = name;
this.fname = fname;
}
}
And then...
List<Foo> foos = new ArrayList<Foo>();
foos.add(new Foo("demo","fdemo"));
foos.add(new Foo("test","fname"));
So you can access them like...
foos.get(0).name;
=> "demo"
You can use the Double Brace Initialization as shown below:
Map<String, Integer> hashMap = new HashMap<String, Integer>()
{{
put("One", 1);
put("Two", 2);
put("Three", 3);
}};
As a piece of warning, please refer to the thread Efficiency of Java “Double Brace Initialization" for the performance implications that it might have.
Convert hashmap to a ArrayList with a pair class
Hashmap<Object,Object> items = new HashMap<>();
to
List<Pair<Object,Object>> items = new ArrayList<>();
so you can sort it as you want, or list sorted by adding order.
Java 8 alternative one-liner for merging two maps:
defaultMap.forEach((k, v) -> destMap.putIfAbsent(k, v));
The same with method reference:
defaultMap.forEach(destMap::putIfAbsent);
Or idemponent for original maps solution with third map:
Map<String, Integer> map3 = new HashMap<String, Integer>(map2);
map1.forEach(map3::putIfAbsent);
And here is a way to merge two maps into fast immutable one with Guava that does least possible intermediate copy operations:
ImmutableMap.Builder<String, Integer> builder = ImmutableMap.<String, Integer>builder();
builder.putAll(map1);
map2.forEach((k, v) -> {if (!map1.containsKey(k)) builder.put(k, v);});
ImmutableMap<String, Integer> map3 = builder.build();
See also Merge two maps with Java 8 for cases when values present in both maps need to be combined with mapping function.
It does this by default. It returns null
.
With Guava 15 you can also simply use:
Set s = Sets.newConcurrentHashSet();
HashMap<String, String> jsonToMap(String JsonDetectionString) throws JSONException {
HashMap<String, String> map = new HashMap<String, String>();
Gson gson = new Gson();
map = (HashMap<String, String>) gson.fromJson(JsonDetectionString, map.getClass());
return map;
}
For the time being I am going a different route than I previous stated. I changed the way I am formatting the data to:
&A2168=1&A1837=5&A8472=1&A1987=2
On the server side I am using getParameterNames() to place all the keys into an Enumerator and then iterating over the Enumerator and placing the keys and values into a HashMap. It looks something like this:
Enumeration keys = request.getParameterNames();
HashMap map = new HashMap();
String key = null;
while(keys.hasMoreElements()){
key = keys.nextElement().toString();
map.put(key, request.getParameter(key));
}
It depends on the algorithm you choose to avoid collisions. If your implementation uses separate chaining then the worst case scenario happens where every data element is hashed to the same value (poor choice of the hash function for example). In that case, data lookup is no different from a linear search on a linked list i.e. O(n). However, the probability of that happening is negligible and lookups best and average cases remain constant i.e. O(1).
You could try using MultiMap instead of HashMap
Initialising it will require fewer lines of codes. Adding and retrieving the values will also make it shorter.
Map<String, List<Integer>> map = new HashMap<String, List<Integer>>();
would become:
Multimap<String, Integer> multiMap = ArrayListMultimap.create();
You can check this link: http://java.dzone.com/articles/hashmap-%E2%80%93-single-key-and
This is what I'm doing in TypeScript I have a little utils library where I put things like this
export const arrayToHash = (array: any[], id: string = 'id') =>
array.reduce((obj, item) => (obj[item[id]] = item , obj), {})
usage:
const hash = arrayToHash([{id:1,data:'data'},{id:2,data:'data'}])
or if you have a identifier other than 'id'
const hash = arrayToHash([{key:1,data:'data'},{key:2,data:'data'}], 'key')
Code example:
HashMap<Integer,String> h = new HashMap<Integer,String> ();
h.put(null,null);
h.put(null, "a");
System.out.println(h);
Output:
{null=a}
It looks like you are willing to create a temporary Map
, so I'd do it like this:
Map tmp = new HashMap(patch);
tmp.keySet().removeAll(target.keySet());
target.putAll(tmp);
Here, patch
is the map that you are adding to the target
map.
Thanks to Louis Wasserman, here's a version that takes advantage of the new methods in Java 8:
patch.forEach(target::putIfAbsent);
For your Q2, there are already answers to your question. For your Q1, and more generally when you know that the key's filtering should give a unique value, there's no need to use Streams at all.
Just use get
or getOrDefault
, i.e:
List<String> list1 = id1.getOrDefault(1, Collections.emptyList());
Assuming you have a JSON hash hanging around somewhere, to automatically convert it into something like WarHog's version, wrap your JSON hash contents in %q{hsh}
tags.
This seems to automatically add all the necessary escaped text like in WarHog's answer.
could you please try below code
<c:forEach var="hash" items="${map['key']}">
<option><c:out value="${hash}"/></option>
</c:forEach>
I'd suggest a three-pronged approach:
Run Java with more memory: java -Xmx256M
for example to run with 256 Megabytes. Use more if needed and you have lots of RAM.
Cache your calculated hash values as suggested by another poster, so each object only calculates its hash value once.
Use a better hashing algorithm. The one you posted would return the same hash where a = {0, 1} as it would where a ={1, 0}, all else being equal.
Utilise what Java gives you for free.
public int hashCode() {
return 31 * Arrays.hashCode(a) + Arrays.hashCode(b);
}
I'm pretty sure this has much less chance of clashing than your existing hashCode method, although it depends on the exact nature of your data.
require 'json/ext' # to use the C based extension instead of json/pure
puts {hash: 123}.to_json
Tested with below sample snippet, tried with MapUtils, and Java8 Stream feature. It worked with both cases.
public static void main(String[] args) {
Map<String, String> test = new HashMap<String, String>();
test.put("a", "1");
test.put("d", "1");
test.put("b", "2");
test.put("c", "3");
test.put("d", "4");
test.put("d", "41");
System.out.println(test);
Map<String, String> test1 = MapUtils.invertMap(test);
System.out.println(test1);
Map<String, String> mapInversed =
test.entrySet()
.stream()
.collect(Collectors.toMap(Map.Entry::getValue, Map.Entry::getKey));
System.out.println(mapInversed);
}
Output:
{a=1, b=2, c=3, d=41}
{1=a, 2=b, 3=c, 41=d}
{1=a, 2=b, 3=c, 41=d}
If you want a copy of the HashMap you need to construct a new one with.
myobjectListB = new HashMap<Integer,myObject>(myobjectListA);
This will create a (shallow) copy of the map.
This is a class I use to create Message Digest hashes
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public class Sha1Hex {
public String makeSHA1Hash(String input)
throws NoSuchAlgorithmException, UnsupportedEncodingException
{
MessageDigest md = MessageDigest.getInstance("SHA1");
md.reset();
byte[] buffer = input.getBytes("UTF-8");
md.update(buffer);
byte[] digest = md.digest();
String hexStr = "";
for (int i = 0; i < digest.length; i++) {
hexStr += Integer.toString( ( digest[i] & 0xff ) + 0x100, 16).substring( 1 );
}
return hexStr;
}
}
Smarter:
for (String key : hashMap.keySet()) {
System.out.println("Key: " + key + ", Value: " + map.get(key));
}
Use sorted TreeMap
:
Map<String, Float> map = new TreeMap<>(yourMap);
It will automatically put entries sorted by keys. I think natural String
ordering will be fine in your case.
Note that HashMap
due to lookup optimizations does not preserve order.
Clone is slow. For performance should probably start with blank hash and merge. Doesn't cover case of nested hashes...
require 'benchmark'
def bench Benchmark.bm do |b|
test = {'a' => 1, 'b' => 2, 'c' => 3, 4 => 'd'}
b.report 'clone' do
1_000_000.times do |i|
h = test.clone
h['new'] = 5
end
end
b.report 'merge' do
1_000_000.times do |i|
h = {}
h['new'] = 5
h.merge! test
end
end
b.report 'inject' do
1_000_000.times do |i|
h = test.inject({}) do |n, (k, v)|
n[k] = v;
n
end
h['new'] = 5
end
end
end
end
bench user system total ( real) clone 1.960000 0.080000 2.040000 ( 2.029604) merge 1.690000 0.080000 1.770000 ( 1.767828) inject 3.120000 0.030000 3.150000 ( 3.152627)
Map
is an interface, i.e. an abstract "thing" that defines how something can be used. HashMap
is an implementation of that interface.
Correct me if I'm wrong but what you're getting at is that with strings, "Hi" == "Hi" doesn't always come out true (because they're not necessarily the same object).
The reason you're getting an answer of 1 though is because the JVM will reuse strings objects where possible. In this case the JVM is reusing the string object, and thus overwriting the item in the Hashmap/Hashset.
But you aren't guaranteed this behavior (because it could be a different string object that has the same value "Hi"). The behavior you see is just because of the JVM's optimization.
In answer to your second question: Yes a HashMap can hold different types of objects. Whether that's a good idea or not depends on the problem you're trying to solve.
That said, your example won't work. The int value is not an Object. You have to use the Integer wrapper class to store an int value in a HashMap
If you want to store multiple values for a key (if I understand you correctly), you could try a MultiHashMap (available in various libraries, not only commons-collections).
Java doesn't want you to make an array of HashMaps, but it will let you make an array of Objects. So, just write up a class declaration as a shell around your HashMap, and make an array of that class. This lets you store some extra data about the HashMaps if you so choose--which can be a benefit, given that you already have a somewhat complex data structure.
What this looks like:
private static someClass[] arr = new someClass[someNum];
and
public class someClass {
private static int dataFoo;
private static int dataBar;
private static HashMap<String, String> yourArray;
...
}
You won't gain anything by checking that the key exists. This is the code of HashMap
:
@Override
public boolean containsKey(Object key) {
Entry<K, V> m = getEntry(key);
return m != null;
}
@Override
public V get(Object key) {
Entry<K, V> m = getEntry(key);
if (m != null) {
return m.value;
}
return null;
}
Just check if the return value for get()
is different from null
.
This is the HashMap source code.
Resources :
I've seen occasional problems with Eclipse forgetting that built-in classes (including Object
and String
) exist. The way I've resolved them is to:
This seems to make Eclipse forget whatever incorrect cached information it had about the available classes.
Basically in HashMap, user has to provide both Key and Value, whereas in HashSet you provide only Value, the Key is derived automatically from Value by using hash function. So after having both Key and Value, HashSet can be stored as HashMap internally.
Below code works for me
first I defined the partnerTypesMap
like below in the server side,
Map<String, String> partnerTypes = new HashMap<>();
after adding values to it I added the object to model
,
model.addAttribute("partnerTypesMap", partnerTypes);
When rendering the page I use below foreach
to print them one by one.
<c:forEach items="${partnerTypesMap}" var="partnerTypesMap">
<form:option value="${partnerTypesMap['value']}">${partnerTypesMap['key']}</form:option>
</c:forEach>
Why do you want to re-invent the wheel, when you already have something to do your work. Map.keySet()
method gives you a Set of all the keys in the Map.
Map<String, Integer> map = new HashMap<String, Integer>();
for (String key: map.keySet()) {
System.out.println("key : " + key);
System.out.println("value : " + map.get(key));
}
Also, your 1st for-loop looks odd to me: -
for(int k = 0; k < list.size(); k++){
map = (HashMap)list.get(k);
}
You are iterating over your list, and assigning each element to the same reference - map
, which will overwrite all the previous values.. All you will be having is the last map in your list.
EDIT: -
You can also use entrySet
if you want both key and value for your map. That would be better bet for you: -
Map<String, Integer> map = new HashMap<String, Integer>();
for(Entry<String, Integer> entry: map.entrySet()) {
System.out.println(entry.getKey());
System.out.println(entry.getValue());
}
P.S.: -
Your code looks jumbled to me. I would suggest, keep that code aside, and think about your design
one more time. For now, as the code stands, it is very difficult to understand what its trying to do.
This can be done as follows :
select CONVERT(VARCHAR(10), GETDATE(), 103) + ' ' + convert(VARCHAR(8), GETDATE(), 14)
Hope it helps
This may be an incorrect parameter to your SOAP call; look at the format of the parameter(s) in the 'data:' json section - this is the payload you are passing over - parameter and data wrapped in JSON format.
Google Chrome's debugging toolbar has some good tools to verify parameters and look at error messages - for example, start with the Console tab and click on the URL which errors or click on the network tab. You will want to view the message's headers, response etc...
If possible, I went with a solution like this. It only works if you want several specific interfaces (e.g. those you have source access to) to be passed as a generic parameter, not any.
IInterface
.IInterface
In source, it looks like this:
Any interface you want to be passed as the generic parameter:
public interface IWhatever : IInterface
{
// IWhatever specific declarations
}
IInterface:
public interface IInterface
{
// Nothing in here, keep moving
}
The class on which you want to put the type constraint:
public class WorldPeaceGenerator<T> where T : IInterface
{
// Actual world peace generating code
}
Another way is to use a transparent 1x1.png with width: 100%
, height: auto
in a div
and absolutely positioned content within it:
html:
<div>
<img src="1x1px.png">
<h1>FOO</h1>
</div>
css:
div {
position: relative;
width: 50%;
}
img {
width: 100%;
height: auto;
}
h1 {
position: absolute;
top: 10px;
left: 10px;
}
usually i don't use for loop in R, but here is my solution using for loops and two packages : plyr and dostats
plyr is on cran and you can download dostats on https://github.com/halpo/dostats (may be using install_github from Hadley devtools package)
Assuming that i have your first two data.frame (Df.1 and Df.2) in csv files, you can do something like this.
require(plyr)
require(dostats)
files <- list.files(pattern = ".csv")
for (i in seq_along(files)) {
assign(paste("Df", i, sep = "."), read.csv(files[i]))
assign(paste(paste("Df", i, sep = ""), "summary", sep = "."),
ldply(get(paste("Df", i, sep = ".")), dostats, sum, min, mean, median, max))
}
Here is the output
R> Df1.summary
.id sum min mean median max
1 A 34 4 5.6667 5.5 8
2 B 22 1 3.6667 3.0 9
R> Df2.summary
.id sum min mean median max
1 A 21 1 3.5000 3.5 6
2 B 16 1 2.6667 2.5 5
How about defining your own view? I have used the class below, using a LinearLayout around a view whose background color is set. This allows me to pre-define layout parameters for it. If you don't need that just extend View and set the background color instead.
public class HorizontalRulerView extends LinearLayout {
static final int COLOR = Color.DKGRAY;
static final int HEIGHT = 2;
static final int VERTICAL_MARGIN = 10;
static final int HORIZONTAL_MARGIN = 5;
static final int TOP_MARGIN = VERTICAL_MARGIN;
static final int BOTTOM_MARGIN = VERTICAL_MARGIN;
static final int LEFT_MARGIN = HORIZONTAL_MARGIN;
static final int RIGHT_MARGIN = HORIZONTAL_MARGIN;
public HorizontalRulerView(Context context) {
this(context, null);
}
public HorizontalRulerView(Context context, AttributeSet attrs) {
this(context, attrs, android.R.attr.textViewStyle);
}
public HorizontalRulerView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
setOrientation(VERTICAL);
View v = new View(context);
v.setBackgroundColor(COLOR);
LayoutParams lp = new LayoutParams(
LayoutParams.MATCH_PARENT,
HEIGHT
);
lp.topMargin = TOP_MARGIN;
lp.bottomMargin = BOTTOM_MARGIN;
lp.leftMargin = LEFT_MARGIN;
lp.rightMargin = RIGHT_MARGIN;
addView(v, lp);
}
}
Use it programmatically or in Eclipse (Custom & Library Views -- just pull it into your layout).
A more modern answer for an old question:
MainActivity.kt
private var myMenuIconEnabled by Delegates.observable(true) { _, old, new ->
if (new != old) invalidateOptionsMenu()
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
findViewById<Button>(R.id.my_button).setOnClickListener { myMenuIconEnabled = false }
}
override fun onCreateOptionsMenu(menu: Menu?): Boolean {
menuInflater.inflate(R.menu.menu_main_activity, menu)
return super.onCreateOptionsMenu(menu)
}
override fun onPrepareOptionsMenu(menu: Menu): Boolean {
menu.findItem(R.id.action_my_action).isEnabled = myMenuIconEnabled
return super.onPrepareOptionsMenu(menu)
}
menu_main_activity.xml
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="@+id/action_my_action"
android:icon="@drawable/ic_my_icon_24dp"
app:iconTint="@drawable/menu_item_icon_selector"
android:title="My title"
app:showAsAction="always" />
</menu>
menu_item_icon_selector.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:color="?enabledMenuIconColor" android:state_enabled="true" />
<item android:color="?disabledMenuIconColor" />
attrs.xml
<resources>
<attr name="enabledMenuIconColor" format="reference|color"/>
<attr name="disabledMenuIconColor" format="reference|color"/>
</resources>
styles.xml or themes.xml
<style name="AppTheme" parent="Theme.MaterialComponents.Light.NoActionBar">
<!-- Customize your theme here. -->
<item name="disabledMenuIconColor">@color/white_30_alpha</item>
<item name="enabledMenuIconColor">@android:color/white</item>
south
plugin:Like T.T suggested in his answer, my previous answer was for south
migration plugin, when Django hasn't any schema migration features.
Now (works in Django 1.9+):
You can try this!
python manage.py makemigrations python manage.py migrate --run-syncdb
south
migrations pluginAs I can see you done it all in wrong order, to fix it up your should complete this checklist (I assume you can't delete sqlite3 database file to start over):
- Grab any SQLite GUI tool (i.e. http://sqliteadmin.orbmu2k.de/)
- Change your model definition to match database definition (best approach is to comment new fields)
- Delete
migrations
folder in your model- Delete rows in
south_migrationhistory
table whereapp_name
match your application name (probablyhomework
)- Invoke:
./manage.py schemamigration <app_name> --initial
- Create tables by
./manage.py migrate <app_name> --fake
(--fake
will skip SQL execute because table already exists in your database)- Make changes to your app's model
- Invoke
./manage.py schemamigration <app_name> --auto
- Then apply changes to database:
./manage.py migrate <app_name>
Steps 7,8,9 repeat whenever your model needs any changes.
Make sure that both projects have same target framework version here: right click on project -> properties -> application (tab) -> target framework
Also, make sure that the project "logger" (which you want to include in the main project) has the output type "Class Library" in: right click on project -> properties -> application (tab) -> output type
Finally, Rebuild the solution.
Simple you can use
db.collectionName.createIndex({urfield:1},{unique:true});
you can use cross apply
:
select
a.x,
bb.y,
bb.z
from
a
cross apply
( select b.y, b.z
from b
where b.v = a.v
) bb
If there will be no row from b to mach row from a then cross apply
wont return row. If you need such a rows then use outer apply
If you need to find only one specific row for each of row from a, try:
cross apply
( select top 1 b.y, b.z
from b
where b.v = a.v
order by b.order
) bb
I think You ask for Boolean algebra which describes the output of various operations performed on boolean variables. Just look at the article on Wikipedia.
Here's a solution that builds off many of the excellent answers. This option is jQuery free, and dynamic, not requiring you to specifically target elements by id.
1) Add your reCAPTCHA markup as you normally would:
<div class="g-recaptcha" data-sitekey="YOUR_KEY_HERE"></div>
2) Add the following into the document. It will work in any browser that supports the querySelectorAll API
<script src="https://www.google.com/recaptcha/api.js?onload=renderRecaptchas&render=explicit" async defer></script>
<script>
window.renderRecaptchas = function() {
var recaptchas = document.querySelectorAll('.g-recaptcha');
for (var i = 0; i < recaptchas.length; i++) {
grecaptcha.render(recaptchas[i], {
sitekey: recaptchas[i].getAttribute('data-sitekey')
});
}
}
</script>
First, I think you're calling it the wrong thing. "JSON" stands for "JavaScript Object Notation" - it's just a specification for representing some data in a string that explicitly mimics JavaScript object (and array, string, number and boolean) literals. You're trying to build up a JavaScript object dynamically - so the word you're looking for is "object".
With that pedantry out of the way, I think that you're asking how to set object and array properties.
// make an empty object
var myObject = {};
// set the "list1" property to an array of strings
myObject.list1 = ['1', '2'];
// you can also access properties by string
myObject['list2'] = [];
// accessing arrays is the same, but the keys are numbers
myObject.list2[0] = 'a';
myObject['list2'][1] = 'b';
myObject.list3 = [];
// instead of placing properties at specific indices, you
// can push them on to the end
myObject.list3.push({});
// or unshift them on to the beginning
myObject.list3.unshift({});
myObject.list3[0]['key1'] = 'value1';
myObject.list3[1]['key2'] = 'value2';
myObject.not_a_list = '11';
That code will build up the object that you specified in your question (except that I call it myObject instead of myJSON). For more information on accessing properties, I recommend the Mozilla JavaScript Guide and the book JavaScript: The Good Parts.
Or simply using my Uri extension
public static Uri AttachParameters(this Uri uri, NameValueCollection parameters)
{
var stringBuilder = new StringBuilder();
string str = "?";
for (int index = 0; index < parameters.Count; ++index)
{
stringBuilder.Append(str + parameters.AllKeys[index] + "=" + parameters[index]);
str = "&";
}
return new Uri(uri + stringBuilder.ToString());
}
Uri uri = new Uri("http://www.example.com/index.php").AttachParameters(new NameValueCollection
{
{"Bill", "Gates"},
{"Steve", "Jobs"}
});
Some browsers support Array.indexOf()
.
If not, you could augment the Array
object via its prototype like so...
if (!Array.prototype.indexOf)
{
Array.prototype.indexOf = function(searchElement /*, fromIndex */)
{
"use strict";
if (this === void 0 || this === null)
throw new TypeError();
var t = Object(this);
var len = t.length >>> 0;
if (len === 0)
return -1;
var n = 0;
if (arguments.length > 0)
{
n = Number(arguments[1]);
if (n !== n) // shortcut for verifying if it's NaN
n = 0;
else if (n !== 0 && n !== (1 / 0) && n !== -(1 / 0))
n = (n > 0 || -1) * Math.floor(Math.abs(n));
}
if (n >= len)
return -1;
var k = n >= 0
? n
: Math.max(len - Math.abs(n), 0);
for (; k < len; k++)
{
if (k in t && t[k] === searchElement)
return k;
}
return -1;
};
}
You need to alter your table. Increase the column width using a DDL statement.
please see here
http://dba-oracle.com/t_alter_table_modify_column_syntax_example.htm
You can do this using the splat operator:
some_func(*params)
This causes the function to receive each list item as a separate parameter. There's a description here: http://docs.python.org/tutorial/controlflow.html#unpacking-argument-lists
For short month names use:
string monthName = new DateTime(2010, 8, 1)
.ToString("MMM", CultureInfo.InvariantCulture);
For long/full month names for Spanish ("es") culture
string fullMonthName = new DateTime(2015, i, 1).ToString("MMMM", CultureInfo.CreateSpecificCulture("es"));
A blanket "no you shouldn't" is terrible advice. This is perfectly reasonable in many situations depending on your use case, workload, data entropy, hardware, etc.. What you shouldn't do is make assumptions.
It should be noted that you can specify a prefix which will limit MySQL's indexing, thereby giving you some help in narrowing down the results before scanning the rest. This may, however, become less useful over time as your prefix "fills up" and becomes less unique.
It's very simple to do, e.g.:
CREATE TABLE IF NOT EXISTS `foo` (
`id` varchar(128),
PRIMARY KEY (`id`(4))
)
Also note that the prefix (4)
appears after the column quotes. Where the 4
means that it should use the first 4 characters of the 128 possible characters that can exist as the id
.
Lastly, you should read how index prefixes work and their limitations before using them: https://dev.mysql.com/doc/refman/8.0/en/create-index.html
About "can it be that 0 errors and IsValid == false": here's MVC source code from https://github.com/Microsoft/referencesource/blob/master/System.Web/ModelBinding/ModelStateDictionary.cs#L37-L41
public bool IsValid {
get {
return Values.All(modelState => modelState.Errors.Count == 0);
}
}
Now, it looks like it can't be. Well, that's for ASP.NET MVC v1.
I prefer this
WHERE CASE WHEN my_col LIKE '%val1%' THEN 1
WHEN my_col LIKE '%val2%' THEN 1
WHEN my_col LIKE '%val3%' THEN 1
ELSE 0
END = 1
I'm not saying it's optimal but it works and it's easily understood. Most of my queries are adhoc used once so performance is generally not an issue for me.
Let's add another solution one to the bunch.
Adding a unique string at the end is a perfect solution.
example.jpg?646413154
Following solution extends this method and provides both the caching capability and fetch a new version when the image is updated.
When the image is updated, the filemtime will be changed.
<?php
$filename = "path/to/images/example.jpg";
$filemtime = filemtime($filename);
?>
Now output the image:
<img src="images/example.jpg?<?php echo $filemtime; ?>" >
Great sadness: neither Cloneable/clone nor a constructor are great solutions: I DON'T WANT TO KNOW THE IMPLEMENTING CLASS!!! (e.g. - I have a Map, which I want copied, using the same hidden MumbleMap implementation) I just want to make a copy, if doing so is supported. But, alas, Cloneable doesn't have the clone method on it, so there is nothing to which you can safely type-cast on which to invoke clone().
Whatever the best "copy object" library out there is, Oracle should make it a standard component of the next Java release (unless it already is, hidden somewhere).
Of course, if more of the library (e.g. - Collections) were immutable, this "copy" task would just go away. But then we would start designing Java programs with things like "class invariants" rather than the verdammt "bean" pattern (make a broken object and mutate until good [enough]).
Use <td valign="top" style="width: 259px">
instead...
Dos commands in my batch file were running only when I type EXIT in command/DOS window. This problem solved when I removed CMD from batch file. No need of it.
I setup a short cut (using windows) and set the target to
C:\Python36\pythonw.exe c:/python36/Lib/idlelib/idle.py
works great
Also found this works
with open('FILE.py') as f:
exec(f.read())
Here are some tips how to begin with simple example.
Consider you have following JSON Array String (similar to yours) like:
var list:Array<Business> = []
// left only 2 fields for demo
struct Business {
var id : Int = 0
var name = ""
}
var jsonStringAsArray = "[\n" +
"{\n" +
"\"id\":72,\n" +
"\"name\":\"Batata Cremosa\",\n" +
"},\n" +
"{\n" +
"\"id\":183,\n" +
"\"name\":\"Caldeirada de Peixes\",\n" +
"},\n" +
"{\n" +
"\"id\":76,\n" +
"\"name\":\"Batata com Cebola e Ervas\",\n" +
"},\n" +
"{\n" +
"\"id\":56,\n" +
"\"name\":\"Arroz de forma\",\n" +
"}]"
// convert String to NSData
var data: NSData = jsonStringAsArray.dataUsingEncoding(NSUTF8StringEncoding)!
var error: NSError?
// convert NSData to 'AnyObject'
let anyObj: AnyObject? = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions(0),
error: &error)
println("Error: \(error)")
// convert 'AnyObject' to Array<Business>
list = self.parseJson(anyObj!)
//===============
func parseJson(anyObj:AnyObject) -> Array<Business>{
var list:Array<Business> = []
if anyObj is Array<AnyObject> {
var b:Business = Business()
for json in anyObj as Array<AnyObject>{
b.name = (json["name"] as AnyObject? as? String) ?? "" // to get rid of null
b.id = (json["id"] as AnyObject? as? Int) ?? 0
list.append(b)
}// for
} // if
return list
}//func
[EDIT]
To get rid of null changed to:
b.name = (json["name"] as AnyObject? as? String) ?? ""
b.id = (json["id"] as AnyObject? as? Int) ?? 0
See also Reference of Coalescing Operator (aka ??
)
Hope it will help you to sort things out,
Try using qx{command}
rather than backticks. To me, it's a bit better because: you can do SQL with it and not worry about escaping quotes and such. Depending on the editor and screen, my old eyes tend to miss the tiny back ticks, and it shouldn't ever have an issue with being overloaded like using angle brackets versus glob.
You do not have to have the RETURN stament.
Have anther look at Using a Stored Procedure with Output Parameters
Also have another look at the OUT section in CREATE PROCEDURE
Logits often are the values of Z function of the output layer in Tensorflow.
use coalesce
COALESCE(value [, ...])
The COALESCE function returns the first of its arguments that is not null. Null is returned only if all arguments are null. It is often used to substitute a default value for null values when data is retrieved for display.
Edit
Here's an example of COALESCE
with your query:
SELECT AVG( price )
FROM(
SELECT *, cume_dist() OVER ( ORDER BY price DESC ) FROM web_price_scan
WHERE listing_Type = 'AARM'
AND u_kbalikepartnumbers_id = 1000307
AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
AND COALESCE( price, 0 ) > ( SELECT AVG( COALESCE( price, 0 ) )* 0.50
FROM ( SELECT *, cume_dist() OVER ( ORDER BY price DESC )
FROM web_price_scan
WHERE listing_Type='AARM'
AND u_kbalikepartnumbers_id = 1000307
AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
) g
WHERE cume_dist < 0.50
)
AND COALESCE( price, 0 ) < ( SELECT AVG( COALESCE( price, 0 ) ) *2
FROM( SELECT *, cume_dist() OVER ( ORDER BY price desc )
FROM web_price_scan
WHERE listing_Type='AARM'
AND u_kbalikepartnumbers_id = 1000307
AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
) d
WHERE cume_dist < 0.50)
)s
HAVING COUNT(*) > 5
IMHO COALESCE
should not be use with AVG
because it modifies the value. NULL
means unknown and nothing else. It's not like using it in SUM
. In this example, if we replace AVG
by SUM
, the result is not distorted. Adding 0 to a sum doesn't hurt anyone but calculating an average with 0 for the unknown values, you don't get the real average.
In that case, I would add price IS NOT NULL
in WHERE
clause to avoid these unknown values.
In addition to @Marc Claesen's answer, I think that an instructive classic example of cache-unfriendly code is code that scans a C bidimensional array (e.g. a bitmap image) column-wise instead of row-wise.
Elements that are adjacent in a row are also adjacent in memory, thus accessing them in sequence means accessing them in ascending memory order; this is cache-friendly, since the cache tends to prefetch contiguous blocks of memory.
Instead, accessing such elements column-wise is cache-unfriendly, since elements on the same column are distant in memory from each other (in particular, their distance is equal to the size of the row), so when you use this access pattern you are jumping around in memory, potentially wasting the effort of the cache of retrieving the elements nearby in memory.
And all that it takes to ruin the performance is to go from
// Cache-friendly version - processes pixels which are adjacent in memory
for(unsigned int y=0; y<height; ++y)
{
for(unsigned int x=0; x<width; ++x)
{
... image[y][x] ...
}
}
to
// Cache-unfriendly version - jumps around in memory for no good reason
for(unsigned int x=0; x<width; ++x)
{
for(unsigned int y=0; y<height; ++y)
{
... image[y][x] ...
}
}
This effect can be quite dramatic (several order of magnitudes in speed) in systems with small caches and/or working with big arrays (e.g. 10+ megapixels 24 bpp images on current machines); for this reason, if you have to do many vertical scans, often it's better to rotate the image of 90 degrees first and perform the various analysis later, limiting the cache-unfriendly code just to the rotation.
First of all, there's no such thing as a JSON object. What you've got in your question is a JavaScript object literal (see here for a great discussion on the difference). Here's how you would go about serializing what you've got to JSON though:
I would use an anonymous type filled with your results
type:
string json = JsonConvert.SerializeObject(new
{
results = new List<Result>()
{
new Result { id = 1, value = "ABC", info = "ABC" },
new Result { id = 2, value = "JKL", info = "JKL" }
}
});
Also, note that the generated JSON has result items with id
s of type Number
instead of strings. I doubt this will be a problem, but it would be easy enough to change the type of id
to string
in the C#.
I'd also tweak your results
type and get rid of the backing fields:
public class Result
{
public int id { get ;set; }
public string value { get; set; }
public string info { get; set; }
}
Furthermore, classes conventionally are PascalCased
and not camelCased
.
Here's the generated JSON from the code above:
{
"results": [
{
"id": 1,
"value": "ABC",
"info": "ABC"
},
{
"id": 2,
"value": "JKL",
"info": "JKL"
}
]
}
You can't do it (yet) with string interpolation. Your best bet is still going to be NSString formatting:
println(NSString(format:"%.2f", sqrt(2.0)))
Extrapolating from python, it seems like a reasonable syntax might be:
@infix func % (value:Double, format:String) -> String {
return NSString(format:format, value)
}
Which then allows you to use them as:
M_PI % "%5.3f" // "3.142"
You can define similar operators for all of the numeric types, unfortunately I haven't found a way to do it with generics.
Swift 5 Update
As of at least Swift 5, String
directly supports the format:
initializer, so there's no need to use NSString
and the @infix
attribute is no longer needed which means the samples above should be written as:
println(String(format:"%.2f", sqrt(2.0)))
func %(value:Double, format:String) -> String {
return String(format:format, value)
}
Double.pi % "%5.3f" // "3.142"
If you are interested in the indexes, the best choice is np.argsort(a)
a = np.random.randint(0, 100, 10)
sorted_idx = np.argsort(a)
The parent component can manage child state passing a prop to child and the child convert this prop in state using componentWillReceiveProps.
class ParentComponent extends Component {
state = { drawerOpen: false }
toggleChildMenu = () => {
this.setState({ drawerOpen: !this.state.drawerOpen })
}
render() {
return (
<div>
<button onClick={this.toggleChildMenu}>Toggle Menu from Parent</button>
<ChildComponent drawerOpen={this.state.drawerOpen} />
</div>
)
}
}
class ChildComponent extends Component {
constructor(props) {
super(props)
this.state = {
open: false
}
}
componentWillReceiveProps(props) {
this.setState({ open: props.drawerOpen })
}
toggleMenu() {
this.setState({
open: !this.state.open
})
}
render() {
return <Drawer open={this.state.open} />
}
}
Example from https://github.com/ffmike/jquery-validate
<label for="spam_email">
<input type="checkbox" class="checkbox" id="spam_email" value="email" name="spam[]" validate="required:true, minlength:2" /> Spam via E-Mail </label>
<label for="spam_phone">
<input type="checkbox" class="checkbox" id="spam_phone" value="phone" name="spam[]" /> Spam via Phone </label>
<label for="spam_mail">
<input type="checkbox" class="checkbox" id="spam_mail" value="mail" name="spam[]" /> Spam via Mail </label>
<label for="spam[]" class="error">Please select at least two types of spam.</label>
The same without field "validate" in tags only using javascript:
$("#testform").validate({
rules: {
"spam[]": {
required: true,
minlength: 1
}
},
messages: {
"spam[]": "Please select at least two types of spam."
}
});
And if you need different names for inputs, you can use somethig like this:
<input type="hidden" name="spam" id="spam"/>
<label for="spam_phone">
<input type="checkbox" class="checkbox" id="spam_phone" value="phone" name="spam_phone" /> Spam via Phone</label>
<label for="spam_mail">
<input type="checkbox" class="checkbox" id="spam_mail" value="mail" name="spam_mail" /> Spam via Mail </label>
Javascript:
$("#testform").validate({
rules: {
spam: {
required: function (element) {
var boxes = $('.checkbox');
if (boxes.filter(':checked').length == 0) {
return true;
}
return false;
},
minlength: 1
}
},
messages: {
spam: "Please select at least two types of spam."
}
});
I have added hidden input before inputs and setting it to "required" if there is no selected checkboxes
This is how I did it with a large (50 GB) file:
I tried 2 different ways: the first, reading the file into memory and using Regex Replace or String Replace. Then I appended the entire string to a temporary file.
The first method works well for a few Regex replacements, but Regex.Replace or String.Replace could cause out of memory error if you do many replaces in a large file.
The second is by reading the temp file line by line and manually building each line using StringBuilder and appending each processed line to the result file. This method was pretty fast.
static void ProcessLargeFile()
{
if (File.Exists(outFileName)) File.Delete(outFileName);
string text = File.ReadAllText(inputFileName, Encoding.UTF8);
// EX 1 This opens entire file in memory and uses Replace and Regex Replace --> might cause out of memory error
text = text.Replace("</text>", "");
text = Regex.Replace(text, @"\<ref.*?\</ref\>", "");
File.WriteAllText(outFileName, text);
// EX 2 This reads file line by line
if (File.Exists(outFileName)) File.Delete(outFileName);
using (var sw = new StreamWriter(outFileName))
using (var fs = File.OpenRead(inFileName))
using (var sr = new StreamReader(fs, Encoding.UTF8)) //use UTF8 encoding or whatever encoding your file uses
{
string line, newLine;
while ((line = sr.ReadLine()) != null)
{
//note: call your own replace function or use String.Replace here
newLine = Util.ReplaceDoubleBrackets(line);
sw.WriteLine(newLine);
}
}
}
public static string ReplaceDoubleBrackets(string str)
{
//note: this replaces the first occurrence of a word delimited by [[ ]]
//replace [[ with your own delimiter
if (str.IndexOf("[[") < 0)
return str;
StringBuilder sb = new StringBuilder();
//this part gets the string to replace, put this in a loop if more than one occurrence per line.
int posStart = str.IndexOf("[[");
int posEnd = str.IndexOf("]]");
int length = posEnd - posStart;
// ... code to replace with newstr
sb.Append(newstr);
return sb.ToString();
}
I think you should take a look at proper concurrency handling mechanisms (threads running into infinite loops doesn't sound good per se, btw). Make sure you read a little about the "killing" or "stopping" Threads topic.
What you are describing,sound very much like a "rendezvous", so you may want to take a look at the CyclicBarrier.
There may be other constructs (like using CountDownLatch for example) that can resolve your problem (one thread waiting with a timeout for the latch, the other should count down the latch if it has done it's work, which would release your first thread either after a timeout or when the latch countdown is invoked).
I usually recommend two books in this area: Concurrent Programming in Java and Java Concurrency in Practice.
You can invoke devenv.exe /diff list1.txt list2.txt
from the VS Developer Command Prompt or, if a Visual Studio instance is already running, you can type Tools.DiffFiles
in the Command window, with a handy file name completion:
In httpd.conf file you need to remove #
#LoadModule rewrite_module modules/mod_rewrite.so
after removing # line will look like this:
LoadModule rewrite_module modules/mod_rewrite.so
And Apache restart
Hey Namratha, If you're asking about changing the text and enabled/disabled state of a UIButton, it can be done pretty easily as follows;
[myButton setTitle:@"Normal State Title" forState:UIControlStateNormal]; // To set the title
[myButton setEnabled:NO]; // To toggle enabled / disabled
If you have created the buttons in the Interface Builder and want to access them in code, you can take advantage of the fact that they are passed in as an argument to the IBAction
calls:
- (IBAction) triggerActionWithSender: (id) sender;
This can be bound to the button and you’ll get the button in the sender
argument when the action is triggered. If that’s not enough (because you need to access the buttons somewhere else than in the actions), declare an outlet for the button:
@property(retain) IBOutlet UIButton *someButton;
Then it’s possible to bind the button in IB to the controller, the NIB loading code will set the property value when loading the interface.
Token: The kind for (keywords,identifier,punctuation character, multi-character operators) is ,simply, a Token.
Pattern: A rule for formation of token from input characters.
Lexeme : Its a sequence of characters in SOURCE PROGRAM matched by a pattern for a token. Basically, its an element of Token.
status tell you what to do.
Unmerged paths:
(use "git reset HEAD <file>..." to unstage)
(use "git add <file>..." to mark resolution)
you probably applied a stash or something else that cause a conflict.
either add, reset, or rm.
I cam up with a recursive solution:
def sumDigits(num):
# print "evaluating:", num
if num < 10:
return num
# solution 1
# res = num/10
# rem = num%10
# print "res:", res, "rem:", rem
# return sumDigits(res+rem)
# solution 2
arr = [int(i) for i in str(num)]
return sumDigits(sum(arr))
# print(sumDigits(1))
# print(sumDigits(49))
print(sumDigits(439230))
# print(sumDigits(439237))
Instead of
InputStream fstream = this.getClass().getResourceAsStream("abc.txt");
use
InputStream fstream = this.getClass().getClassLoader().getResourceAsStream("abc.txt");
In this way it will look from the root, not from the path of the current invoking class
$("body").on({
click: function(){alert("left click");},
contextmenu: function(){alert("right click");}
});
You are using both ternary operator
and if
condition, use any one.
By ternary operator:
.map(id => {
return this.props.schema.collectionName.length < 0 ?
<Expandable>
<ObjectDisplay
key={id}
parentDocumentId={id}
schema={schema[this.props.schema.collectionName]}
value={this.props.collection.documents[id]}
/>
</Expandable>
:
<h1>hejsan</h1>
}
By if condition:
.map(id => {
if(this.props.schema.collectionName.length < 0)
return <Expandable>
<ObjectDisplay
key={id}
parentDocumentId={id}
schema={schema[this.props.schema.collectionName]}
value={this.props.collection.documents[id]}
/>
</Expandable>
return <h1>hejsan</h1>
}
If you don't want use jQuery:
function check_pass() {
if (document.getElementById('password').value ==
document.getElementById('confirm_password').value) {
document.getElementById('submit').disabled = false;
} else {
document.getElementById('submit').disabled = true;
}
}
<input type="password" name="password" id="password" onchange='check_pass();'/>
<input type="password" name="confirm_password" id="confirm_password" onchange='check_pass();'/>
<input type="submit" name="submit" value="registration" id="submit" disabled/>
"an object" of what type?
You can certainly assign NULL
(and nullptr
) to objects of pointer types, and it is implementation defined if you can assign NULL
to objects of arithmetic types.
If you mean objects of some class type, the answer is NO (excepting classes that have operator=
accepting pointer or arithmetic types)
"empty" is more plausible, as many types have both copy assignment and default construction (often implicitly). To see if an existing object is like a default constructed one, you will also need an appropriate bool operator==
import os
path = chap_name
if not os.path.exists(path):
os.makedirs(path)
filename = img_alt + '.jpg'
with open(os.path.join(path, filename), 'wb') as temp_file:
temp_file.write(buff)
Key point is to use os.makedirs
in place of os.mkdir
. It is recursive, i.e. it generates all intermediate directories. See http://docs.python.org/library/os.html
Open the file in binary mode as you are storing binary (jpeg) data.
In response to Edit 2, if img_alt sometimes has '/' in it:
img_alt = os.path.basename(img_alt)
Try this more succinct code:
Sub LoopOverEachColumn()
Dim WS As Worksheet
For Each WS In ThisWorkbook.Worksheets
ResizeColumns WS
Next WS
End Sub
Private Sub ResizeColumns(WS As Worksheet)
Dim StrSize As String
Dim ColIter As Long
StrSize = "20.14;9.71;35.86;30.57;23.57;21.43;18.43;23.86;27.43;36.71;30.29;31.14;31;41.14;33.86"
For ColIter = 1 To 15
WS.Columns(ColIter).ColumnWidth = Split(StrSize, ";")(ColIter - 1)
Next ColIter
End Sub
If you want additional columns, just change 1 to 15
to 1 to X
where X
is the column index of the column you want, and append the column size you want to StrSize
.
For example, if you want P:P
to have a width of 25
, just add ;25
to StrSize
and change ColIter...
to ColIter = 1 to 16
.
Hope this helps.
Destroying a PHP Session
A PHP session can be destroyed by session_destroy() function. This function does not need any argument and a single call can destroy all the session variables. If you want to destroy a single session variable then you can use unset() function to unset a session variable.
Here is the example to unset a single variable
<?php unset($_SESSION['counter']); ?>
Here is the call which will destroy all the session variables
<?php session_destroy(); ?>
git rev-parse HEAD
does the trick.
If you need to store it to checkout back later than saving actual branch if any may be preferable:
cat .git/HEAD
Example output:
ref: refs/heads/master
Parse it:
cat .git/HEAD | sed "s/^.\+ \(.\+\)$/\1/g"`
If you have Windows then you may consider using wsl.exe:
wsl cat .git/HEAD | wsl sed "s/^.\+ \(.\+\)$/\1/g"
Output:
refs/heads/master
This value may be used to git checkout later but it becomes pointing to its SHA. To make it to point to the actual current branch by its name do:
wsl cat .git/HEAD | wsl sed "s/^.\+ \(.\+\)$/\1/g" | wsl sed "s/^refs\///g" | wsl sed "s/^heads\///g"
Output:
master
just click file in your android studio then click Sync Project with Gradle Files..
if it won't work, click Build click Clean Project.
it always work for me
//add this to your css
.myClass{
margin 0 auto;
}
// add the class to the span tag( could add it to the div and not using a span
// at all
<div class="row">
<div class="col-xs-1 center-block">
<span class="myClass">aaaaaaaaaaaaaaaaaaaaaaaaaaa</span>
</div>
</div>
you can do so by using the :before
or :after
pseudo. read more about it here http://astronautweb.co/snippet/font-awesome/
change your code to this
.lb-prev:hover {
filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=100);
opacity: 1;
text-decoration: none;
}
.lb-prev:before {
font-family: FontAwesome;
content: "\f053";
font-size: 30px;
}
do the same for the other icons. you might want to adjust the color and height of the icons too. anyway here is the fiddle hope this helps
Check next lines in you app build.gradle file.
android {
compileSdkVersion 25 <--- Set exist in local machine sdk version.
buildToolsVersion '25.0.3' <--- Set exist build tools version.
}
Let the resolver automatically do that.
Inside A controller:
public class AController : ApiController
{
private readonly BController _bController;
public AController(
BController bController)
{
_bController = bController;
}
public httpMethod{
var result = _bController.OtherMethodBController(parameters);
....
}
}
Copying to the clipboard is a tricky task to do in Javascript in terms of browser compatibility. The best way to do it is using a small flash. It will work on every browser. You can check it in this article.
Here's how to do it for Internet Explorer:
function copy (str)
{
//for IE ONLY!
window.clipboardData.setData('Text',str);
}
Use example with from the post of Szilágyi Donát.
I use two querys, one to know what roles I have, excluding connect grant:
SELECT * FROM USER_ROLE_PRIVS WHERE GRANTED_ROLE != 'CONNECT'; -- Roles of the actual Oracle Schema
Know I like to find what privileges/roles my schema/user have; examples of my roles ROLE_VIEW_PAYMENTS & ROLE_OPS_CUSTOMERS. But to find the tables/objecst of an specific role I used:
SELECT * FROM ALL_TAB_PRIVS WHERE GRANTEE='ROLE_OPS_CUSTOMERS'; -- Objects granted at role.
The owner schema for this example could be PRD_CUSTOMERS_OWNER (or the role/schema inself).
Regards.
T-SQL
/*
Stored Procedure GetstudentnameInOutputVariable is modified to collect the
email address of the student with the help of the Alert Keyword
*/
CREATE PROCEDURE GetstudentnameInOutputVariable
(
@studentid INT, --Input parameter , Studentid of the student
@studentname VARCHAR (200) OUT, -- Output parameter to collect the student name
@StudentEmail VARCHAR (200)OUT -- Output Parameter to collect the student email
)
AS
BEGIN
SELECT @studentname= Firstname+' '+Lastname,
@StudentEmail=email FROM tbl_Students WHERE studentid=@studentid
END
Here is a slight adaptation for Typescript that will also return the dates for the week start and week end. I think it's common to have to display those in a user interface, since people don't usually remember week numbers.
function getWeekNumber(d: Date) {
// Copy date so don't modify original
d = new Date(Date.UTC(d.getFullYear(), d.getMonth(), d.getDate()));
// Set to nearest Thursday: current date + 4 - current day number Make
// Sunday's day number 7
d.setUTCDate(d.getUTCDate() + 4 - (d.getUTCDay() || 7));
// Get first day of year
const yearStart = new Date(Date.UTC(d.getUTCFullYear(), 0, 1));
// Calculate full weeks to nearest Thursday
const weekNo = Math.ceil(
((d.getTime() - yearStart.getTime()) / 86400000 + 1) / 7
);
const weekStartDate = new Date(d.getTime());
weekStartDate.setUTCDate(weekStartDate.getUTCDate() - 3);
const weekEndDate = new Date(d.getTime());
weekEndDate.setUTCDate(weekEndDate.getUTCDate() + 3);
return [d.getUTCFullYear(), weekNo, weekStartDate, weekEndDate] as const;
}
_x000D_
System variables can be set through CMD and registry For ex. reg query "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v PATH
All the commonly used CMD codes and system variables are given here: Set Windows system environment variables using CMD.
Open CMD and type Set
You will get all the values of system variable.
Type set java to know the path details of java installed on your window OS.
^https?://
You might have to escape the forward slashes though, depending on context.
background:url('/image/url/') right top scroll;
background-size: auto 100%;
min-height:100%;
encountered same exact symptops. above worked for me.
What you'd have to do is send a request to the server for it to do the check, and then send back the result to you.
What type of server are you trying to communicate with? You may need to write a small service to respond to the request.
Not sure what language you're using (you didn't specify), but you should be able to "escape" the quotation mark character with a backslash: "\"ROM\""
PreparedStatement doesn't provide any good way to deal with SQL IN clause. Per http://www.javaranch.com/journal/200510/Journal200510.jsp#a2 "You can't substitute things that are meant to become part of the SQL statement. This is necessary because if the SQL itself can change, the driver can't precompile the statement. It also has the nice side effect of preventing SQL injection attacks." I ended up using following approach:
String query = "SELECT my_column FROM my_table where search_column IN ($searchColumns)";
query = query.replace("$searchColumns", "'A', 'B', 'C'");
Statement stmt = connection.createStatement();
boolean hasResults = stmt.execute(query);
do {
if (hasResults)
return stmt.getResultSet();
hasResults = stmt.getMoreResults();
} while (hasResults || stmt.getUpdateCount() != -1);
IF,
Then,
It is highly recommended that you install xampp 1.7.0 . Download Link
Note: This is not a solution to the above problem, but a FIX which would allow you to continue with your development.
Here are the rules for how these functions work:
stringValue.CompareTo(otherStringValue)
null
comes before a stringCultureInfo.CurrentCulture.CompareInfo.Compare
, which means it will use a culture-dependent comparison. This might mean that ß
will compare equal to SS
in Germany, or similarstringValue.Equals(otherStringValue)
null
is not considered equal to anythingStringComparison
option, it will use what looks like a direct ordinal equality check, i.e. ß
is not the same as SS
, in any language or culturestringValue == otherStringValue
stringValue.Equals()
.==
operator calls the static Equals(string a, string b)
method (which in turn goes to an internal EqualsHelper
to do the comparison..Equals()
on a null
string gets null
reference exception, while on ==
does not.Object.ReferenceEquals(stringValue, otherStringValue)
Just checks that references are the same, i.e. it isn't just two strings with the same contents, you're comparing a string object with itself.
Note that with the options above that use method calls, there are overloads with more options to specify how to compare.
My advice if you just want to check for equality is to make up your mind whether you want to use a culture-dependent comparison or not, and then use .CompareTo
or .Equals
, depending on the choice.
I don't think it's possible with bluetooth, but you could try looking into WiFi Peer-to-Peer,
which allows one-to-many connections.
This is similar to, but more general than, @Jacob Relkin's solution:
This is ES2015:
const randomChoice = arr => {
const randIndex = Math.floor(Math.random() * arr.length);
return arr[randIndex];
};
The code works by selecting a random number between 0 and the length of the array, then returning the item at that index.
Try:
//Difference in days
var diff = Math.floor(( start - end ) / 86400000);
alert(diff);
Last or next date, week, month & year calculation. It might be helpful for anyone.
Current Date:
select curdate();
Yesterday:
select subdate(curdate(), 1)
Tomorrow:
select adddate(curdate(), 1)
Last 1 week:
select between subdate(curdate(), 7) and subdate(curdate(), 1)
Next 1 week:
between adddate(curdate(), 7) and adddate(curdate(), 1)
Last 1 month:
between subdate(curdate(), 30) and subdate(curdate(), 1)
Next 1 month:
between adddate(curdate(), 30) and adddate(curdate(), 1)
Current month:
subdate(curdate(),day(curdate())-1) and last_day(curdate());
Last 1 year:
between subdate(curdate(), 365) and subdate(curdate(), 1)
Next 1 year:
between adddate(curdate(), 365) and adddate(curdate(), 1)
Does it have something to do with preventing other events on the page from firing?
Yes.
Setting async to false means that the statement you are calling has to complete before the next statement in your function can be called. If you set async: true then that statement will begin it's execution and the next statement will be called regardless of whether the async statement has completed yet.
For more insight see: jQuery ajax success anonymous function scope
you can do this:
file= open(r'D:\\zzzz\\names2.txt')
file_split=set(file.read().split())
print(len(file_split))
In practice many sites use id
attributes starting with numbers, even though this is technically not valid HTML.
The HTML 5 draft specification loosens up the rules for the id
and name
attributes: they are now just opaque strings which cannot contain spaces.
you are missing fields.iteritems()
in your code.
You could also do it other way, where you get values using keys in the dictionary.
for key in fields:
value = fields[key]
You can specify the default
named parameter in the json.dumps()
function:
json.dumps(obj, default=lambda x: x.__dict__)
Explanation:
``default(obj)`` is a function that should return a serializable version
of obj or raise TypeError. The default simply raises TypeError.
(Works on Python 2.7 and Python 3.x)
Note: In this case you need instance
variables and not class
variables, as the example in the question tries to do. (I am assuming the asker meant class instance
to be an object of a class)
I learned this first from @phihag's answer here. Found it to be the simplest and cleanest way to do the job.
Android Studio 1.3b1 (not sure about other versions) autocompleted my internet permission to ANDROID.PERMISSION.INTERNET
. Changing it to android.permission.INTERNET
fixed the issue.
Solution mentioned here --> Multidex Issue solution worked for me. Below is what needs to be added to Application context :
@Override
protected void attachBaseContext(Context base) {
super.attachBaseContext(base);
MultiDex.install(this);
}
Either !=
or ne
will work, but you need to get the accessor syntax and nested quotes sorted out.
<c:if test="${content.contentType.name ne 'MCE'}">
<%-- snip --%>
</c:if>
Add this to your code:
.child { width: 100%; }
We know that a block-level child is supposed to occupy the full width of the parent.
Chrome understands this.
IE11, for whatever reason, wants an explicit request.
Using flex-basis: 100%
or flex: 1
also works.
.parent {_x000D_
display: flex;_x000D_
flex-direction: column;_x000D_
width: 400px;_x000D_
border: 1px solid red;_x000D_
align-items: center;_x000D_
}_x000D_
.child {_x000D_
border: 1px solid blue;_x000D_
width: calc(100% - 2px); /* NEW; used calc to adjust for parent borders */_x000D_
}
_x000D_
<div class="parent">_x000D_
<div class="child">_x000D_
Lorem Ipsum is simply dummy text of the printing and typesetting industry_x000D_
</div>_x000D_
<div class="child">_x000D_
Lorem Ipsum is simply dummy text of the printing and typesetting industry_x000D_
</div>_x000D_
</div>
_x000D_
Note: Sometimes it will be necessary to sort through the various levels of the HTML structure to pinpoint which container gets the width: 100%
. CSS wrap text not working in IE
var doc = new XmlDocument();
doc.Loadxml(@"c:\abc.xml");
Its pretty straight forward to do it with only shell
while read A B C; do
echo "$C"
done < oldfile >newfile
R defines a ~
(tilde) operator for use in formulas. Formulas have all sorts of uses, but perhaps the most common is for regression:
library(datasets)
lm( myFormula, data=iris)
help("~")
or help("formula")
will teach you more.
@Spacedman has covered the basics. Let's discuss how it works.
First, being an operator, note that it is essentially a shortcut to a function (with two arguments):
> `~`(lhs,rhs)
lhs ~ rhs
> lhs ~ rhs
lhs ~ rhs
That can be helpful to know for use in e.g. apply
family commands.
Second, you can manipulate the formula as text:
oldform <- as.character(myFormula) # Get components
myFormula <- as.formula( paste( oldform[2], "Sepal.Length", sep="~" ) )
Third, you can manipulate it as a list:
myFormula[[2]]
myFormula[[3]]
Finally, there are some helpful tricks with formulae (see help("formula")
for more):
myFormula <- Species ~ .
For example, the version above is the same as the original version, since the dot means "all variables not yet used." This looks at the data.frame you use in your eventual model call, sees which variables exist in the data.frame but aren't explicitly mentioned in your formula, and replaces the dot with those missing variables.
Code for Python 3.6.1
print("This first text and " , end="")
print("second text will be on the same line")
print("Unlike this text which will be on a newline")
Output
>>>
This first text and second text will be on the same line
Unlike this text which will be on a newline
I got this error when I had incorrect keypair in .ssh. Adding the pubkey to github (in settings) fixed this issue for me.
As of now (NOV-2019), graph.api V5.0
graph API says, refer graph api
A link to the person's Timeline. The link will only resolve if the person clicking the link is logged into Facebook and is a friend of the person whose profile is being viewed.
Another option is to use a list comprehension:
df['First Season'] = [1 if year > 1990 else year for year in df['First Season']]
As of January 2020 and Xcode 11.3.1 -
Xcode will automatically create an Apple Distribution certificate, install it in Keychain Access, and update Xcode's signing information
(Note: the single Apple Distribution certificate is now provided instead of the previous iOS Distribution certificate and equivalents.)
You're using smart quotes. That is, instead of standard quotation marks ("
), you are using curly quotes (”
). This happens automatically with Microsoft Word and other word processors to make things look prettier, but it also mangles HTML. Make sure to code in a plain text editor, like Notepad or Notepad2.
<html>
<head>
<title>HTML in 10 Simple Steps or Less</title>
<meta http-equiv="refresh" content="5"> <!-- See the difference? -->
</head>
<body>
</body>
</html>
You found the shorthand to set privileges for all existing tables in the given schema. The manual clarifies:
(but note that
ALL TABLES
is considered to include views and foreign tables).
Bold emphasis mine. serial
columns are implemented with nextval()
on a sequence as column default and, quoting the manual:
For sequences, this privilege allows the use of the
currval
andnextval
functions.
So if there are serial
columns, you'll also want to grant USAGE
(or ALL PRIVILEGES
) on sequences
GRANT USAGE ON ALL SEQUENCES IN SCHEMA foo TO mygrp;
Note: identity columns in Postgres 10 or later use implicit sequences that don't require additional privileges. (Consider upgrading serial
columns.)
You'll also be interested in DEFAULT PRIVILEGES
for users or schemas:
ALTER DEFAULT PRIVILEGES IN SCHEMA foo GRANT ALL PRIVILEGES ON TABLES TO staff;
ALTER DEFAULT PRIVILEGES IN SCHEMA foo GRANT USAGE ON SEQUENCES TO staff;
ALTER DEFAULT PRIVILEGES IN SCHEMA foo REVOKE ...;
This sets privileges for objects created in the future automatically - but not for pre-existing objects.
Default privileges are only applied to objects created by the targeted user (FOR ROLE my_creating_role
). If that clause is omitted, it defaults to the current user executing ALTER DEFAULT PRIVILEGES
. To be explicit:
ALTER DEFAULT PRIVILEGES FOR ROLE my_creating_role IN SCHEMA foo GRANT ...;
ALTER DEFAULT PRIVILEGES FOR ROLE my_creating_role IN SCHEMA foo REVOKE ...;
Note also that all versions of pgAdmin III have a subtle bug and display default privileges in the SQL pane, even if they do not apply to the current role. Be sure to adjust the FOR ROLE
clause manually when copying the SQL script.
You could also do this with a union query. As the number of columns increase, you would need to modify the query, but at least it would be a straight forward modification.
Select T.Id, T.Col1, T.Col2, T.Col3, A.TheMin
From YourTable T
Inner Join (
Select A.Id, Min(A.Col1) As TheMin
From (
Select Id, Col1
From YourTable
Union All
Select Id, Col2
From YourTable
Union All
Select Id, Col3
From YourTable
) As A
Group By A.Id
) As A
On T.Id = A.Id
I would recommend start using Lyx, with that you can use Latex just as easy as OOO-Writer. It gives you the possibility to step into Latex deeper by manually adding Latex-Code to your Document. PDF is just one klick away after installatioin. Lyx is cross-plattform.
As a general rule:
Double representation is good enough in most cases but can miserably fail in some situations. Use decimal values if you need complete precision (as in financial applications).
Most problems with doubles doesn't come from direct comparison, it use to be a result of the accumulation of several math operations which exponentially disturb the value due to rounding and fractional errors (especially with multiplications and divisions).
Check your logic, if the code is:
x = 0.1
if (x == 0.1)
it should not fail, it's to simple to fail, if X value is calculated by more complex means or operations it's quite possible the ToString method used by the debugger is using an smart rounding, maybe you can do the same (if that's too risky go back to using decimal):
if (x.ToString() == "0.1")
If you have some params, you can do this.
$results = DB::table('rooms')
->distinct()
->leftJoin('bookings', function($join) use ($param1, $param2)
{
$join->on('rooms.id', '=', 'bookings.room_type_id');
$join->on('arrival','=',DB::raw("'".$param1."'"));
$join->on('arrival','=',DB::raw("'".$param2."'"));
})
->where('bookings.room_type_id', '=', NULL)
->get();
and then return your query
return $results;
Try rmtree()
in shutil
from the Python standard library
There is another example which I would like to share with you
:D
http://www.sommarskog.se/dynamic_sql.html#cursor0
With mongoose it's as simple as:
collection.find().sort('-date').exec(function(err, collectionItems) {
// here's your code
})
I know that the question is two years old, but it was the first result of what I am looking for. I found a good answers and I hope I can help other users.
I will make this brief:
use the $_SERVER["PHP_SELF"]
Variable with htmlspecialchars
():
`htmlspecialchars($_SERVER["PHP_SELF"]);`
PHP_SELF returns the filename of the currently executing script.
htmlspecialchars
() function converts special characters to HTML entities.
--> NO XSSBeing curious but still unable to find the answer to the performance topic of the question above, I wrote this gist for nodejs to test both the performance and reliability of all presented (and scored) solutions.
I've compared the wall times of a clone function creation and the execution of a clone. The results together with assertion errors are included in the gist's comment.
Plus my two cents (based on the author's suggestion):
clone0 cent (faster but uglier):
Function.prototype.clone = function() {
var newfun;
eval('newfun=' + this.toString());
for (var key in this)
newfun[key] = this[key];
return newfun;
};
clone4 cent (slower but for those who dislike eval() for purposes known only to them and their ancestors):
Function.prototype.clone = function() {
var newfun = new Function('return ' + this.toString())();
for (var key in this)
newfun[key] = this[key];
return newfun;
};
As for the performance, if eval/new Function is slower than wrapper solution (and it really depends on the function body size), it gives you bare function clone (and I mean the true shallow clone with properties but unshared state) without unnecessary fuzz with hidden properties, wrapper functions and problems with stack.
Plus there is always one important factor you need to take into consideration: the less code, the less places for mistakes.
The downside of using the eval/new Function is that the clone and the original function will operate in different scopes. It won't work well with functions that are using scoped variables. The solutions using bind-like wrapping are scope independent.
I think you may be confusing Javascript with jQuery methods. Vanilla or plain Javascript is something like:
function example() {
}
A function of that nature can be called at any time, anywhere.
jQuery (a library built on Javascript) has built in functions that generally required the DOM to be fully rendered before being called. The syntax for when this is completed is:
$(document).ready(function() {
});
So a jQuery function, which is prefixed with the $
or the word jQuery
generally is called from within that method.
$(document).ready(function() {
// Assign all list items on the page to be the color red.
// This does not work until AFTER the entire DOM is "ready", hence the $(document).ready()
$('li').css('color', 'red');
});
The pseudo-code for that block is:
When the document object model $(document)
is ready .ready()
, call the following function function() { }
. In that function, check for all <li>
's on the page $('li')
and using the jQuery method .CSS() to set the CSS property "color" to the value "red" .css('color', 'red');
I have my images in a separate class library ("MyClassLibrary") and they are placed in the folder "Images". In the example I used "myImage.jpg" as the background image.
ImageBrush myBrush = new ImageBrush();
Image image = new Image();
image.Source = new BitmapImage(
new Uri(
"pack://application:,,,/MyClassLibrary;component/Images/myImage.jpg"));
myBrush.ImageSource = image.Source;
Grid grid = new Grid();
grid.Background = myBrush;
This method is easy and powerful.
Value is a date and "DD-MM-YYYY" is the mask of the date.
moment().diff(moment(value, "DD-MM-YYYY"), 'years');
Run this command on your terminal.
git reset HEAD~n
You can remove the last n commits from local repo e.g. HEAD~2. Proceed with force git push on your repository.
git push -f origin <branch>
Hope this helps!
try to change the compileSdkVersion to: compileSdkVersion 28
Just update Visual Studio, this is the simplest solution that worked for me.
Here is an example:
Via css:
<style>
.my-table {
page-break-before: always;
page-break-after: always;
}
.my-table tr {
page-break-inside: avoid;
}
</style>
or directly on the element:
<table style="page-break-before: always; page-break-after: always;">
<tr style="page-break-inside: avoid;">
..
</tr>
</table>
This is a two step process:
Remove tracking of file/folder - but keep them on disk - using
git rm --cached
Now they do not show up as "changed" but still show as
untracked files in git status -u
Add them to .gitignore
Browser > Inspect > Element >
<.app-root _nghost-hey-c0="" ng-version="8.2.11">
In terminal
:> ng version
:> ng --version
:> ng -v
var a = 10;
myFunction(a);
function myFunction(a){
window['a'] = 20; // or window.a
}
alert("Value of 'a' outside the function " + a); //outputs 20
With window['variableName'] or window.variableName you can modify the value of a global variable inside a function.
You can use the ElementAt extension method on the list.
For example:
// Get the first item from the list
using System.Linq;
var myList = new List<string>{ "Yes", "No", "Maybe"};
var firstItem = myList.ElementAt(0);
// Do something with firstItem
I guess ch
is a declared as char
. Since char
is a primitive data type and not and object, you can't call any methof from it. You should use Character.isLetter(ch)
.
The easiest way that I could find to pass a message from my app to facebook was programmatically copy to the clipboard and alert the user that they have the option to paste. It saves the user from manually doing it; my app is not pasting but the user might.
...
if (app.equals("facebook")) {
// overcome fb 'putExtra' constraint;
// copy message to clipboard for user to paste into fb.
ClipboardManager cb = (ClipboardManager)
getSystemService(Context.CLIPBOARD_SERVICE);
ClipData clip = ClipData.newPlainText("post", msg);
cb.setPrimaryClip(clip);
// tell the to PASTE POST with option to stop showing this dialogue
showDialog(this, getString(R.string.facebook_post));
}
startActivity(appIntent);
...
I suffered this problem while developing an application for a client. Working on my machine the code/forms etc worked perfectly but when loaded on to the client's system this error occurred at some point within my application.
My workaround for this error was to strip apart the workbook from the forms and code by removing the VBA modules and forms. After doing this my client copied the 'bare' workbook and the modules and forms. Importing the forms and code into the macro-enabled workbook enabled the application to work again.
<script>
$(document).ready(function () {
var msg = '@ViewBag.ErrorMessage'
if (msg.length > 0)
OnFailure('Register', msg);
});
function OnSuccess(header,Message) {
$("#Message_Header").text(header);
$("#Message_Text").text(Message);
$('#MessageDialog').modal('show');
}
function OnFailure(header,error)
{
$("#Message_Header").text(header);
$("#Message_Text").text(error);
$('#MessageDialog').modal('show');
}
</script>
For a pure JS solution (no CSS classes), just set the transition
to 'none'
. To restore the transition as specified in the CSS, set the transition
to an empty string.
// Remove the transition
elem.style.transition = 'none';
// Restore the transition
elem.style.transition = '';
If you're using vendor prefixes, you'll need to set those too.
elem.style.webkitTransition = 'none'
I'll get back to you on instanceof performance. But a way to avoid problem (or lack thereof) altogether would be to create a parent interface to all the subclasses on which you need to do instanceof. The interface will be a super set of all the methods in sub-classes for which you need to do instanceof check. Where a method does not apply to a specific sub-class, simply provide a dummy implementation of this method. If I didn't misunderstand the issue, this is how I've gotten around the problem in the past.
I like this approach
my_hash = {}
my_hash["goals"] = 3 #to show number
my_hash["penalties"] = "5" #to show string
print("I scored %(goals)d goals and took %(penalties)s penalties" % my_hash)
Note the appended d and s to the brackets respectively.
output will be:
I scored 3 goals and took 5 penalties
you must #include <algorithm>
, then you can use std::find
+=
is just a shortcut for writing
number = 4
number = number + 1
So instead you would write
numbers = 4
numbers += 1
Both ways are correct but example two helps you write a little less code
I recommend to use SMO (Enable TCP/IP Network Protocol for SQL Server). However, it was not available in my case.
I rewrote the WMI commands from Krzysztof Kozielczyk to PowerShell.
# Enable TCP/IP
Get-CimInstance -Namespace root/Microsoft/SqlServer/ComputerManagement10 -ClassName ServerNetworkProtocol -Filter "InstanceName = 'SQLEXPRESS' and ProtocolName = 'Tcp'" |
Invoke-CimMethod -Name SetEnable
# Open the right ports in the firewall
New-NetFirewallRule -DisplayName 'MSSQL$SQLEXPRESS' -Direction Inbound -Action Allow -Protocol TCP -LocalPort 1433
# Modify TCP/IP properties to enable an IP address
$properties = Get-CimInstance -Namespace root/Microsoft/SqlServer/ComputerManagement10 -ClassName ServerNetworkProtocolProperty -Filter "InstanceName='SQLEXPRESS' and ProtocolName = 'Tcp' and IPAddressName='IPAll'"
$properties | ? { $_.PropertyName -eq 'TcpPort' } | Invoke-CimMethod -Name SetStringValue -Arguments @{ StrValue = '1433' }
$properties | ? { $_.PropertyName -eq 'TcpPortDynamic' } | Invoke-CimMethod -Name SetStringValue -Arguments @{ StrValue = '' }
# Restart SQL Server
Restart-Service 'MSSQL$SQLEXPRESS'
Facelets is a XML based view technology. The &
is a special character in XML representing the start of an entity like &
which ends with the ;
character. You'd need to either escape it, which is ugly:
rendered="#{beanA.prompt == true && beanB.currentBase != null}"
or to use the and
keyword instead, which is preferred as to readability and maintainability:
rendered="#{beanA.prompt == true and beanB.currentBase != null}"
Unrelated to the concrete problem, comparing booleans with booleans makes little sense when the expression expects a boolean outcome already. I'd get rid of == true
:
rendered="#{beanA.prompt and beanB.currentBase != null}"
In vb60 you can do this:
Public Cn As ADODB.Connection
'open connection
Dim Rs As ADODB.Recordset
Set Rs = Cn.OpenSchema(adSchemaColumns, Array(Empty, Empty, UCase("Table"), UCase("field")))
'and sample (valRs is my function for rs.fields("CHARACTER_MAXIMUM_LENGTH").value):
RT_Charactar_Maximum_Length = (ValRS(Rs, "CHARACTER_MAXIMUM_LENGTH"))
rt_Tipo = (ValRS(Rs, "DATA_TYPE"))
True
... and False
obviously.
Otherwise, None
evaluates to False, as does the integer 0
and also the float 0.0
(although I wouldn't use floats like that).
Also, empty lists []
, empty tuplets ()
, and empty strings ''
or ""
evaluate to False.
Try it yourself with the function bool()
:
bool([])
bool(['a value'])
bool('')
bool('A string')
bool(True) # ;-)
bool(False)
bool(0)
bool(None)
bool(0.0)
bool(1)
etc..
If you'd like a list of owners, and the count of the number of tables per owner, try:
SELECT distinct owner, count(table_name) FROM dba_tables GROUP BY owner;
Use http://facebook.github.io/stetho/ library to access your app's local storage with chrome inspect tools. You can find sharedPreference file under Local storage -> < your app's package name >
You had the identity
node as a child of authentication
node. That was the issue. As in the example above, authentication
and identity
nodes must be children of the system.web
node
I did the following to get my Mac to see the devices again:
android update adb
adb kill-server
adb start-server
At this point, calling adb devices
started returning devices again. Now run or debug your project to test it on your device.
You can use the "system( string $command[, int &$return_var] ) : string" function. For Windows system( "time" );, system( "time > output.txt" ); to put the response in the output.txt file. If you plan on deploying your website on someone else's server, then you may not want to hardcode the server time, as the server may move to an unknown timezone. Then it may be best to set the default time zone in the php.ini file. I use Hostinger and they allow you to configure that php.ini value.
Have you exposed the X-Token
from server side using access-control-expose-headers
? because not all headers are allowed to be accessed from the client side, you need to expose them from the server side
Also in your frontend, you can use new HTTP module to get a full response using {observe: 'response'}
like
http
.get<any>('url', {observe: 'response'})
.subscribe(resp => {
console.log(resp.headers.get('X-Token'));
});
Basically, the problem lies in block12. for the block1/2 to take up the total height of the block12, it must have a defined height. This stack overflow post explains that in really good detail.
So setting a defined height for block12 will allow you to set a proper height. I have created an example on JSfiddle that will show you the the blocks can be floated next to one another if the block12 div is set to a standard height through out the page.
Here is an example including a header and block3 div with some content in for examples.
#header{
position:absolute;
top:0;
left:0;
width:100%;
height:20%;
}
#block12{
position:absolute;
top:20%;
width:100%;
left:0;
height:40%;
}
#block1,#block2{
float:left;
overflow-y: scroll;
text-align:center;
color:red;
width:50%;
height:100%;
}
#clear{clear:both;}
#block3{
position:absolute;
bottom:0;
color:blue;
height:40%;
}
It helps to trace the exception. For example you are writing some methods in your program and one of your methods causes bug. Then printstack will help you to identify which method causes the bug. Stack will help like this:
First your main method will be called and inserted to stack, then the second method will be called and inserted to the stack in LIFO order and if any error occurs somewhere inside any method then this stack will help to identify that method.
I had issues with spaces showing in between my output and there was no answer online at all to fix this issue. I literally spend many hours trying to find a solution and found one from playing around with the code to the point that I almost did not even know what I typed in at the time that I got it to work. Here is my fix for the issue: [System.Text.Encoding]::UTF8.GetString(([System.Convert]::FromBase64String($base64string)|?{$_}))
You need to add:
#include <cstdlib>
in order for the compiler to see the prototype for system()
.
This worked for me:
location / {
alias /path/to/my/indexfile/;
try_files $uri /index.html;
}
This allowed me to create a catch-all URL for a javascript single-page app. All static files like css, fonts, and javascript built by npm run build
will be found if they are in the same directory as index.html
.
If the static files were in another directory, for some reason, you'd also need something like:
# Static pages generated by "npm run build"
location ~ ^/css/|^/fonts/|^/semantic/|^/static/ {
alias /path/to/my/staticfiles/;
}
If you are experienced with SQL Server, I would recommend ASP.NET.
ADO.NET gives you good access to SQL Server, and with SMO, you will also have just about the best access to SQL Server features. You can access SQL Server from other environments, but nothing is quite as integrated or predictable.
You can call your stored procs with SqlCommand and process the results the SqlDataReader and you'll be in business.
I use App.getRes()
instead of App.getContext().getResources()
(as @Cristian answered)
It is very simple to use anywhere in your code!
So here is a unique solution by which you can access resources from anywhere like Util class
.
(1) Create or Edit your Application
class.
import android.app.Application;
import android.content.res.Resources;
public class App extends Application {
private static App mInstance;
private static Resources res;
@Override
public void onCreate() {
super.onCreate();
mInstance = this;
res = getResources();
}
public static App getInstance() {
return mInstance;
}
public static Resources getRes() {
return res;
}
}
(2) Add name field to your manifest.xml
<application
tag. (or Skip this if already there)
<application
android:name=".App"
...
>
...
</application>
Now you are good to go.
App.getRes().getString(R.string.some_id)
anywhere in code.You might be looking for this Microsoft Ajax Content Delivery Network So you could just add
<script src="http://ajax.microsoft.com/ajax/jquery/jquery-1.4.2.min.js" type="text/javascript"></script>
To your aspx page.
The native library file name has to correspond to the Jar file name. This is very very important. Please make sure that jar name and dll name are same. Also,please see the post from Fabian Steeg My download for jawin was containing different names for dll and jar. It was jawin.jar and jawind.dll, note extra 'd' in dll file name. I simply renamed it to jawin.dll and set it as a native library in eclipse as mentioned in post "http://www.eclipsezone.com/eclipse/forums/t49342.html"
Every Ansible task when run can save its results into a variable. To do this, you have to specify which variable to save the results into. Do this with the register
parameter, independently of the module used.
Once you save the results to a variable you can use it later in any of the subsequent tasks. So for example if you want to get the standard output of a specific task you can write the following:
---
- hosts: localhost
tasks:
- shell: ls
register: shell_result
- debug:
var: shell_result.stdout_lines
Here register
tells ansible to save the response of the module into the shell_result
variable, and then we use the debug
module to print the variable out.
An example run would look like the this:
PLAY [localhost] ***************************************************************
TASK [command] *****************************************************************
changed: [localhost]
TASK [debug] *******************************************************************
ok: [localhost] => {
"shell_result.stdout_lines": [
"play.yml"
]
}
Responses can contain multiple fields. stdout_lines
is one of the default fields you can expect from a module's response.
Not all fields are available from all modules, for example for a module which doesn't return anything to the standard out you wouldn't expect anything in the stdout
or stdout_lines
values, however the msg
field might be filled in this case. Also there are some modules where you might find something in a non-standard variable, for these you can try to consult the module's documentation for these non-standard return values.
Alternatively you can increase the verbosity level of ansible-playbook. You can choose between different verbosity levels: -v
, -vvv
and -vvvv
. For example when running the playbook with verbosity (-vvv
) you get this:
PLAY [localhost] ***************************************************************
TASK [command] *****************************************************************
(...)
changed: [localhost] => {
"changed": true,
"cmd": "ls",
"delta": "0:00:00.007621",
"end": "2017-02-17 23:04:41.912570",
"invocation": {
"module_args": {
"_raw_params": "ls",
"_uses_shell": true,
"chdir": null,
"creates": null,
"executable": null,
"removes": null,
"warn": true
},
"module_name": "command"
},
"rc": 0,
"start": "2017-02-17 23:04:41.904949",
"stderr": "",
"stdout": "play.retry\nplay.yml",
"stdout_lines": [
"play.retry",
"play.yml"
],
"warnings": []
}
As you can see this will print out the response of each of the modules, and all of the fields available. You can see that the stdout_lines
is available, and its contents are what we expect.
To answer your main question about the jenkins_script
module, if you check its documentation, you can see that it returns the output in the output
field, so you might want to try the following:
tasks:
- jenkins_script:
script: (...)
register: jenkins_result
- debug:
var: jenkins_result.output
Setting the tab size in nano
cd /etc
ls -a
sudo nano nanorc
Link: https://app.gitbook.com/@cai-dat-chrome-ubuntu-18-04/s/chuaphanloai/setting-the-tab-size-in-nano
UITapGestureRecognizer *singleTap = [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(doSingleTap)] autorelease];
singleTap.numberOfTapsRequired = 1;
[self.view addGestureRecognizer:singleTap];
UITapGestureRecognizer *doubleTap = [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(doDoubleTap)] autorelease];
doubleTap.numberOfTapsRequired = 2;
[self.view addGestureRecognizer:doubleTap];
[singleTap requireGestureRecognizerToFail:doubleTap];
Note: If you are using numberOfTouchesRequired
it has to be .numberOfTouchesRequired = 1;
For Swift
let singleTapGesture = UITapGestureRecognizer(target: self, action: #selector(didPressPartButton))
singleTapGesture.numberOfTapsRequired = 1
view.addGestureRecognizer(singleTapGesture)
let doubleTapGesture = UITapGestureRecognizer(target: self, action: #selector(didDoubleTap))
doubleTapGesture.numberOfTapsRequired = 2
view.addGestureRecognizer(doubleTapGesture)
singleTapGesture.require(toFail: doubleTapGesture)
in mysql workbench server>>>>>>export Data then follow instructions it will generate insert statements for all tables data each table will has .sql file for all its contained data
You need to:
mysql path\data
ib_logfile0
and ib_logfile1
.With WinForms you can use the ErrorProvider in conjunction with the Validating
event to handle the validation of user input. The Validating
event provides the hook to perform the validation and ErrorProvider gives a nice consistent approach to providing the user with feedback on any error conditions.
http://msdn.microsoft.com/en-us/library/system.windows.forms.errorprovider.aspx
This should work:
start "" "c:\program files\php\php.exe" D:\mydocs\mp\index.php param1 param2
The start
command interprets the first argument as a window title if it contains spaces. In this case, that means start
considers your whole argument a title and sees no command. Passing ""
(an empty title) as the first argument to start
fixes the problem.
you can try this
CSS:
#table-wrapper {
height:150px;
overflow:auto;
margin-top:20px;
}
#table-wrapper table {
width:100%;
color:#000;
}
#table-wrapper table thead th .text {
position:fixed;
top:0px;
height:20px;
width:35%;
border:1px solid red;
}
HTML:
<div id="table-wrapper">
<table>
<thead>
<tr>
<th><span class="text">album</span></th>
<th><span class="text">song</span></th>
<th><span class="text">genre</span></th>
</tr>
</thead>
<tbody>
<tr> <td> album 0</td> <td> song0</td> <td> genre0</td> </tr>
<tr> <td>album 1</td> <td>song 1</td> <td> genre1</td> </tr>
<tr> <td> album2</td> <td>song 2</td> <td> genre2</td> </tr>
<tr> <td> album3</td> <td>song 3</td> <td> genre3</td> </tr>
<tr> <td> album4</td> <td>song 4</td> <td>genre 4</td> </tr>
<tr> <td> album5</td> <td>song 5</td> <td>genre 5</td> </tr>
<tr> <td>album 6</td> <td> song6</td> <td> genre6</td> </tr>
<tr> <td>album 7</td> <td> song7</td> <td> genre7</td> </tr>
<tr> <td> album8</td> <td> song8</td> <td>genre 8</td> </tr>
<tr> <td> album9</td> <td> song9</td> <td> genre9</td> </tr>
<tr> <td> album10</td> <td>song 10</td> <td> genre10</td> </tr>
<tr> <td> album11</td> <td>song 11</td> <td> genre11</td> </tr>
<tr> <td> album12</td> <td> song12</td> <td> genre12</td> </tr>
<tr> <td>album 13</td> <td> song13</td> <td> genre13</td> </tr>
<tr> <td> album14</td> <td> song14</td> <td> genre14</td> </tr>
<tr> <td> album15</td> <td> song15</td> <td> genre15</td> </tr>
<tr> <td>album 16</td> <td> song16</td> <td> genre16</td> </tr>
<tr> <td>album 17</td> <td> song17</td> <td> genre17</td> </tr>
<tr> <td> album18</td> <td> song18</td> <td> genre18</td> </tr>
<tr> <td> album19</td> <td> song19</td> <td> genre19</td> </tr>
<tr> <td> album20</td> <td> song20</td> <td> genre20</td> </tr>
</tbody>
</table>
</div>
Check this fiddle : http://jsfiddle.net/Kritika/GLKxB/1/
this will keep the table
head fixed
,and scroll
only the table content
.
On client:
axios.get('/api', {
params: {
foo: 'bar'
}
});
On server:
function get(req, res, next) {
let param = req.query.foo
.....
}
Wikipedia will give all the information you need here. Quoting from http://en.wikipedia.org/wiki/URI:
A URL is a URI that, in addition to identifying a resource, provides means of acting upon or obtaining a representation of the resource by describing its primary access mechanism or network "location".
we can write the UTF-8 encoded file with java using use PrintWriter to write UTF-8 encoded xml
Or Click here
PrintWriter out1 = new PrintWriter(new File("C:\\abc.xml"), "UTF-8");
You asked about performance. See this perf test comparing 'concat', '+' and 'join' - in short the + operator wins by far.
Try this:
@keyframes animationName {
0% { opacity:0; }
50% { opacity:1; }
100% { opacity:0; }
}
@-o-keyframes animationName{
0% { opacity:0; }
50% { opacity:1; }
100% { opacity:0; }
}
@-moz-keyframes animationName{
0% { opacity:0; }
50% { opacity:1; }
100% { opacity:0; }
}
@-webkit-keyframes animationName{
0% { opacity:0; }
50% { opacity:1; }
100% { opacity:0; }
}
.elementToFadeInAndOut {
-webkit-animation: animationName 5s infinite;
-moz-animation: animationName 5s infinite;
-o-animation: animationName 5s infinite;
animation: animationName 5s infinite;
}
For records == 0, rjmunro's solution gives 1. The correct solution is 0. That said, if you know that records > 0 (and I'm sure we've all assumed recordsPerPage > 0), then rjmunro solution gives correct results and does not have any of the overflow issues.
int pageCount = 0;
if (records > 0)
{
pageCount = (((records - 1) / recordsPerPage) + 1);
}
// no else required
All the integer math solutions are going to be more efficient than any of the floating point solutions.
Both are very much similar , but if you have a large number of parameters for object creation with some of them optional with some default values , go for Builder pattern.
Selenium2Library has get_location():
import Selenium2Library
s = Selenium2Library.Selenium2Library()
url = s.get_location()
In Asp.net Core use:
using Newtonsoft.Json
var obj = new { MyValue = 1 };
var json = JsonConvert.SerializeObject(obj);
var obj2 = JsonConvert.DeserializeObject(json);
This is what worked for me...
import cv2
import numpy as np
#Created an image (really an ndarray) with three channels
new_image = np.ndarray((3, num_rows, num_cols), dtype=int)
#Did manipulations for my project where my array values went way over 255
#Eventually returned numbers to between 0 and 255
#Converted the datatype to np.uint8
new_image = new_image.astype(np.uint8)
#Separated the channels in my new image
new_image_red, new_image_green, new_image_blue = new_image
#Stacked the channels
new_rgb = np.dstack([new_image_red, new_image_green, new_image_blue])
#Displayed the image
cv2.imshow("WindowNameHere", new_rgbrgb)
cv2.waitKey(0)
For the simple email like [email protected], below code is sufficient.
public static bool ValidateEmail(string email)
{
System.Text.RegularExpressions.Regex emailRegex = new System.Text.RegularExpressions.Regex(@"^([\w\.\-]+)@([\w\-]+)((\.(\w){2,3})+)$");
System.Text.RegularExpressions.Match emailMatch = emailRegex.Match(email);
return emailMatch.Success;
}
The answer is on the example link you provided:
http://getbootstrap.com/javascript/#modals-usage
i.e.
Call a modal with id myModal with a single line of JavaScript:
$('#myModal').modal('show');
Relative paths can be best understood if you know how Java runs the program.
There is a concept of working directory when running programs in Java. Assuming you have a class, say, FileHelper
that does the IO under
/User/home/Desktop/projectRoot/src/topLevelPackage/
.
Depending on the case where you invoke java
to run the program, you will have different working directory. If you run your program from within and IDE, it will most probably be projectRoot
.
In this case $ projectRoot/src : java topLevelPackage.FileHelper
it will be src
.
In this case $ projectRoot : java -cp src topLevelPackage.FileHelper
it will be projectRoot
.
In this case $ /User/home/Desktop : java -cp ./projectRoot/src topLevelPackage.FileHelper
it will be Desktop
.
(Assuming $ is your command prompt with standard Unix-like FileSystem. Similar correspondence/parallels with Windows system)
So, your relative path root (.)
resolves to your working directory. Thus to be better sure of where to write files, it's said to consider below approach.
package topLevelPackage
import java.io.File;
import java.nio.file.Path;
import java.nio.file.Paths;
public class FileHelper {
// Not full implementation, just barebone stub for path
public void createLocalFile() {
// Explicitly get hold of working directory
String workingDir = System.getProperty("user.dir");
Path filePath = Paths.get(workingDir+File.separator+"sampleFile.txt");
// In case we need specific path, traverse that path, rather using . or ..
Path pathToProjectRoot = Paths.get(System.getProperty("user.home"), "Desktop", "projectRoot");
System.out.println(filePath);
System.out.println(pathToProjectRoot);
}
}
Hope this helps.
set height: auto;
If you want to have minimum height to x then you can write
height:auto;
min-height:30px;
height:auto !important; /* for IE as it does not support min-height */
height:30px; /* for IE as it does not support min-height */
If you wish to do this dynamically in a "program" try this code:
My point is, you may not know the exact name of the module to "hardcode" it.
It may be selected from a list or may not be currently running to use __file__.
(I know, it will not work in Python 3)
global modpath
modname = 'os' #This can be any module name on the fly
#Create a file called "modname.py"
f=open("modname.py","w")
f.write("import "+modname+"\n")
f.write("modpath = "+modname+"\n")
f.close()
#Call the file with execfile()
execfile('modname.py')
print modpath
<module 'os' from 'C:\Python27\lib\os.pyc'>
I tried to get rid of the "global" issue but found cases where it did not work I think "execfile()" can be emulated in Python 3 Since this is in a program, it can easily be put in a method or module for reuse.
Use -B, -A or -C option
grep --help
...
-B, --before-context=NUM print NUM lines of leading context
-A, --after-context=NUM print NUM lines of trailing context
-C, --context=NUM print NUM lines of output context
-NUM same as --context=NUM
...
Due to the way Python works, it is necessary for it to run your modules when it imports them.
To prevent code in the module from being executed when imported, but only when run directly, you can guard it with this if
:
if __name__ == "__main__":
# this won't be run when imported
You may want to put this code in a main()
method, so that you can either execute the file directly, or import the module and call the main()
. For example, assume this is in the file foo.py
.
def main():
print "Hello World"
if __name__ == "__main__":
main()
This program can be run either by going python foo.py
, or from another Python script:
import foo
...
foo.main()
The correct character (comma or colon) depends on the purpose.
Comma (,
) will sum only the two cells in question.
Colon (:
) will sum all the cells within the range with corners defined by those two cells.
This improved version should work as reliably as a parser.
// Applies to URI, not just URL or URN:
// http://en.wikipedia.org/wiki/Uniform_Resource_Identifier#Relationship_to_URL_and_URN
//
// http://labs.apache.org/webarch/uri/rfc/rfc3986.html#regexp
//
// (?:([^:/?#]+):)?(?://([^/?#]*))?([^?#]*)(?:\?([^#]*))?(?:#(.*))?
//
// http://en.wikipedia.org/wiki/URI_scheme#Generic_syntax
//
// $@ matches the entire uri
// $1 matches scheme (ftp, http, mailto, mshelp, ymsgr, etc)
// $2 matches authority (host, user:pwd@host, etc)
// $3 matches path
// $4 matches query (http GET REST api, etc)
// $5 matches fragment (html anchor, etc)
//
// Match specific schemes, non-optional authority, disallow white-space so can delimit in text, and allow 'www.' w/o scheme
// Note the schemes must match ^[^\s|:/?#]+(?:\|[^\s|:/?#]+)*$
//
// (?:()(www\.[^\s/?#]+\.[^\s/?#]+)|(schemes)://([^\s/?#]*))([^\s?#]*)(?:\?([^\s#]*))?(#(\S*))?
//
// Validate the authority with an orthogonal RegExp, so the RegExp above won’t fail to match any valid urls.
function uriRegExp( flags, schemes/* = null*/, noSubMatches/* = false*/ )
{
if( !schemes )
schemes = '[^\\s:\/?#]+'
else if( !RegExp( /^[^\s|:\/?#]+(?:\|[^\s|:\/?#]+)*$/ ).test( schemes ) )
throw TypeError( 'expected URI schemes' )
return noSubMatches ? new RegExp( '(?:www\\.[^\\s/?#]+\\.[^\\s/?#]+|' + schemes + '://[^\\s/?#]*)[^\\s?#]*(?:\\?[^\\s#]*)?(?:#\\S*)?', flags ) :
new RegExp( '(?:()(www\\.[^\\s/?#]+\\.[^\\s/?#]+)|(' + schemes + ')://([^\\s/?#]*))([^\\s?#]*)(?:\\?([^\\s#]*))?(?:#(\\S*))?', flags )
}
// http://en.wikipedia.org/wiki/URI_scheme#Official_IANA-registered_schemes
function uriSchemesRegExp()
{
return 'about|callto|ftp|gtalk|http|https|irc|ircs|javascript|mailto|mshelp|sftp|ssh|steam|tel|view-source|ymsgr'
}
You'll have to write the SQL DML yourself explicitly. i.e.
UPDATE <table>
SET <column> = NULL;
Once it has completed you'll need to commit your updates
commit;
If you only want to set certain records to NULL use a WHERE clause in your UPDATE statement.
As your original question is pretty vague I hope this covers what you want.
Make sure vartabstop
is unset
set vartabstop=
Set tabstop
to 4
set tabstop=4
As I see it for now I can say that dynamic programming is an extension of divide and conquer paradigm.
I would not treat them as something completely different. Because they both work by recursively breaking down a problem into two or more sub-problems of the same or related type, until these become simple enough to be solved directly. The solutions to the sub-problems are then combined to give a solution to the original problem.
So why do we still have different paradigm names then and why I called dynamic programming an extension. It is because dynamic programming approach may be applied to the problem only if the problem has certain restrictions or prerequisites. And after that dynamic programming extends divide and conquer approach with memoization or tabulation technique.
Let’s go step by step…
As we’ve just discovered there are two key attributes that divide and conquer problem must have in order for dynamic programming to be applicable:
Optimal substructure — optimal solution can be constructed from optimal solutions of its subproblems
Overlapping sub-problems — problem can be broken down into subproblems which are reused several times or a recursive algorithm for the problem solves the same subproblem over and over rather than always generating new subproblems
Once these two conditions are met we can say that this divide and conquer problem may be solved using dynamic programming approach.
Dynamic programming approach extends divide and conquer approach with two techniques (memoization and tabulation) that both have a purpose of storing and re-using sub-problems solutions that may drastically improve performance. For example naive recursive implementation of Fibonacci function has time complexity of O(2^n)
where DP solution doing the same with only O(n)
time.
Memoization (top-down cache filling) refers to the technique of caching and reusing previously computed results. The memoized fib
function would thus look like this:
memFib(n) {
if (mem[n] is undefined)
if (n < 2) result = n
else result = memFib(n-2) + memFib(n-1)
mem[n] = result
return mem[n]
}
Tabulation (bottom-up cache filling) is similar but focuses on filling the entries of the cache. Computing the values in the cache is easiest done iteratively. The tabulation version of fib
would look like this:
tabFib(n) {
mem[0] = 0
mem[1] = 1
for i = 2...n
mem[i] = mem[i-2] + mem[i-1]
return mem[n]
}
You may read more about memoization and tabulation comparison here.
The main idea you should grasp here is that because our divide and conquer problem has overlapping sub-problems the caching of sub-problem solutions becomes possible and thus memoization/tabulation step up onto the scene.
Since we’re now familiar with DP prerequisites and its methodologies we’re ready to put all that was mentioned above into one picture.
If you want to see code examples you may take a look at more detailed explanation here where you'll find two algorithm examples: Binary Search and Minimum Edit Distance (Levenshtein Distance) that are illustrating the difference between DP and DC.
How I redirect to an area is add it as a parameter
@Html.Action("Action", "Controller", new { area = "AreaName" })
for the href portion of a link I use
@Url.Action("Action", "Controller", new { area = "AreaName" })
I want to add an additional piece of information her about the difference in performance.
We already know that due to the fact that ArrayList
implementation is backed by an Object[]
it's supports random access and dynamic resizing and LinkedList
implementation uses references to head and tail to navigate it. It has no random access capabilities, but it supports dynamic resizing as well.
The first thing is that with an ArrayList, you can immediately access the index, whereas with a LinkedList, you have iterate down the object chain.
Secondly, inserting into ArrayList is generally slower because it has to grow once you hit its boundaries. It will have to create a new bigger array, and copy data from the original one.
But the interesting thing is that when you create an ArrayList that is already huge enough to fit all your inserts it will obviously not involve any array copying operations. Adding to it will be even faster than with LinkedList because LinkedList will have to deal with its pointers, while huge ArrayList just sets value at given index.
Check out for more ArrayList and LinkedList differences.
I don't know much about HTML and CSS design strategies, but if you're looking for something simple and that will fit the screen automatically (as I am) I believe the most straight forward solution is to make the divs behave as words in a paragraph. Try specifying display: inline-block
<div style="display: inline-block">
Content in column A
</div>
<div style="display: inline-block">
Content in column B
</div>
You might or might not need to specify the width of the DIVs
If the project came with a Visual Studio project file, then that should already be configured to find the headers for you. If not, you'll have to add the include file directory to the project settings by right-clicking the project and selecting Properties, clicking on "C/C++", and adding the directory containing the include files to the "Additional Include Directories" edit box.
There are multiple suggestions here, but as far as I can see the jQuery UI guys have broken the dialogue control at present.
I say this because I include a dialogue on my page, and its semi transparent and the modal blanking div is behind some other elements. That can't be right!
In the end based on some other posts I developed this global solution, as an extension to the dialogue widget. It works for me but I'm not sure what it would do if I opened a dialogue from within a dialogue.
Basically it looks for the zIndex of everything else on the page and moves the .ui-widget-overlay to be one higher, and the dialogue itself to be one higher than that.
$.widget("ui.dialog", $.ui.dialog,
{
open: function ()
{
var $dialog = $(this.element[0]);
var maxZ = 0;
$('*').each(function ()
{
var thisZ = $(this).css('zIndex');
thisZ = (thisZ === 'auto' ? (Number(maxZ) + 1) : thisZ);
if (thisZ > maxZ) maxZ = thisZ;
});
$(".ui-widget-overlay").css("zIndex", (maxZ + 1));
$dialog.parent().css("zIndex", (maxZ + 2));
return this._super();
}
});
Thanks to the following, as this is where I got the info from of how to do this: https://stackoverflow.com/a/20942857
http://learn.jquery.com/jquery-ui/widget-factory/extending-widgets/
I actually just wrote my own script for this purpose. It doesn't use Xcode. (It's based off a similar script in the Gambit Scheme project.)
Basically, it runs ./configure and make three times (for i386, armv7, and armv7s), and combines each of the resulting libraries into a fat lib.
One possible solution uses JavaScript on the client.
The client algorithm:
The server algorithm:
Client source code (JavaScript):
function getCookie( name ) {
var parts = document.cookie.split(name + "=");
if (parts.length == 2) return parts.pop().split(";").shift();
}
function expireCookie( cName ) {
document.cookie =
encodeURIComponent(cName) + "=deleted; expires=" + new Date( 0 ).toUTCString();
}
function setCursor( docStyle, buttonStyle ) {
document.getElementById( "doc" ).style.cursor = docStyle;
document.getElementById( "button-id" ).style.cursor = buttonStyle;
}
function setFormToken() {
var downloadToken = new Date().getTime();
document.getElementById( "downloadToken" ).value = downloadToken;
return downloadToken;
}
var downloadTimer;
var attempts = 30;
// Prevents double-submits by waiting for a cookie from the server.
function blockResubmit() {
var downloadToken = setFormToken();
setCursor( "wait", "wait" );
downloadTimer = window.setInterval( function() {
var token = getCookie( "downloadToken" );
if( (token == downloadToken) || (attempts == 0) ) {
unblockSubmit();
}
attempts--;
}, 1000 );
}
function unblockSubmit() {
setCursor( "auto", "pointer" );
window.clearInterval( downloadTimer );
expireCookie( "downloadToken" );
attempts = 30;
}
Example server code (PHP):
$TOKEN = "downloadToken";
// Sets a cookie so that when the download begins the browser can
// unblock the submit button (thus helping to prevent multiple clicks).
// The false parameter allows the cookie to be exposed to JavaScript.
$this->setCookieToken( $TOKEN, $_GET[ $TOKEN ], false );
$result = $this->sendFile();
Where:
public function setCookieToken(
$cookieName, $cookieValue, $httpOnly = true, $secure = false ) {
// See: http://stackoverflow.com/a/1459794/59087
// See: http://shiflett.org/blog/2006/mar/server-name-versus-http-host
// See: http://stackoverflow.com/a/3290474/59087
setcookie(
$cookieName,
$cookieValue,
2147483647, // expires January 1, 2038
"/", // your path
$_SERVER["HTTP_HOST"], // your domain
$secure, // Use true over HTTPS
$httpOnly // Set true for $AUTH_COOKIE_NAME
);
}
Edited, will work for unknown max() values:
select name, length( name )
from my_table
where length( name ) = ( select max( length( name ) ) from my_table );
Try using Java 8 predicate test method
Here is a full example of it.
import java.util.Arrays;
import java.util.List;
import java.util.function.Predicate;
public class Test {
public static final List<String> VALUES = Arrays.asList("AA", "AB", "BC", "CD", "AE");
public static void main(String args[]) {
Predicate<String> containsLetterA = VALUES -> VALUES.contains("AB");
for (String i : VALUES) {
System.out.println(containsLetterA.test(i));
}
}
}
http://mytechnologythought.blogspot.com/2019/10/java-8-predicate-test-method-example.html
https://github.com/VipulGulhane1/java8/blob/master/Test.java
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 ...
Here's a version to convert each value in a hex string to it's two's complement version.
In [5159]: twoscomplement('f0079debdd9abe0fdb8adca9dbc89a807b707f')
Out[5159]: '10097325337652013586346735487680959091'
def twoscomplement(hm):
twoscomplement=''
for x in range(0,len(hm)):
value = int(hm[x],16)
if value % 2 == 1:
twoscomplement+=hex(value ^ 14)[2:]
else:
twoscomplement+=hex(((value-1)^15)&0xf)[2:]
return twoscomplement
When we open a modal it accept size as a paramenter:
Possible values for it size: sm, md, lg
$scope.openModal = function (size) {
var modal = $modal.open({
size: size,
templateUrl: "/app/user/welcome.html",
......
});
}
HTML:
<button type="button"
class="btn btn-default"
ng-click="openModal('sm')">Small Modal</button>
<button type="button"
class="btn btn-default"
ng-click="openModal('md')">Medium Modal</button>
<button type="button"
class="btn btn-default"
ng-click="openModal('lg')">Large Modal</button>
If you want any specific size, add style on model HTML:
<style>.modal-dialog {width: 500px;} </style>
XAML:
<ComboBox Height="23" HorizontalAlignment="Left" Margin="19,123,0,0" Name="comboBox1" VerticalAlignment="Top" Width="33" ItemsSource="{Binding}" AllowDrop="True" AlternationCount="1">
<ComboBoxItem Content="1" Name="ComboBoxItem1" />
<ComboBoxItem Content="2" Name="ComboBoxItem2" />
<ComboBoxItem Content="3" Name="ComboBoxItem3" />
</ComboBox>
C#:
if (ComboBoxItem1.IsSelected)
{
// Your code
}
else if (ComboBoxItem2.IsSelected)
{
// Your code
}
else if(ComboBoxItem3.IsSelected)
{
// Your code
}
A good resource start off point would be MSDN as your looking into a microsoft product
The answer by Nils describes how to convert objects to maps, which I found very useful. However, the OP was also wondering where this information is in the MDN docs. While it may not have been there when the question was originally asked, it is now on the MDN page for Object.entries() under the heading Converting an Object to a Map which states:
Converting an Object to a Map
The
new Map()
constructor accepts an iterable ofentries
. WithObject.entries
, you can easily convert fromObject
toMap
:const obj = { foo: 'bar', baz: 42 }; const map = new Map(Object.entries(obj)); console.log(map); // Map { foo: "bar", baz: 42 }
may be this will help also:
.navbar .divider-vertical {
margin-top: 14px;
height: 24px;
border-left: 1px solid #f2f2f2;
border-image: linear-gradient(to bottom, gray, rgba(0, 0, 0, 0)) 1 100%;
}
You should be able to do it simply by adding a -r
wget -r http://stackoverflow.com/
Enumerable.Repeat(String.Empty, count).ToArray()
Will create array of empty strings repeated 'count' times. In case you want to initialize array with same yet special default element value. Careful with reference types, all elements will refer same object.
In my particular case, I fixed this error by looking in the Event Viewer to get a clue as to the source of the issue:
I then followed the steps outlined at Rebuilding Master Database in SQL Server.
Note: Take some good backups first. After erasing the master database, you will have to attach to all of your existing databases again by browsing to the
.mdf files
.
In my particular case, the command to rebuild the master database was:
C:\Program Files\Microsoft SQL Server\110\Setup Bootstrap\SQLServer2012>setup /ACTION=rebuilddatabase /INSTANCENAME=MSSQLSERVER /SQLSYSADMINACCOUNTS=mike /sapwd=[insert password]
Note that this will reset SQL server to its defaults, so you will have to hope that you can restore the master database from E:\backup\master.bak
. I couldn't find this file, so attached the existing databases (by browsing to the existing .mdf
files), and everything was back to normal.
After fixing everything, I created a maintenance plan to back up everything, including the master database, on a weekly basis.
In my particular case, this whole issue was caused by a Seagate hard drive getting bad sectors a couple of months after its 2-year warranty period expired. Most of the Seagate drives I have ever owned have ended up expiring either before or shortly after warranty - so I'm avoiding Seagate like the plague now!!
working for me after turn off ads block extension in chrome, this error sometime appear because something that block http in browser
The following regex matches alphanumeric characters and underscore:
^[a-zA-Z0-9_]+$
For example, in Perl:
#!/usr/bin/perl -w
my $arg1 = $ARGV[0];
# check that the string contains *only* one or more alphanumeric chars or underscores
if ($arg1 !~ /^[a-zA-Z0-9_]+$/) {
print "Failed.\n";
} else {
print "Success.\n";
}
tldr; fetch the file from the url, store it as a local Blob, inject a link element into the DOM, and click it to download the Blob
I had a PDF file that was stored in S3 behind a Cloudfront URL. I wanted the user to be able to click a button and immediately initiate a download without popping open a new tab with a PDF preview. Generally, if a file is hosted at a URL that has a different domain that the site the user is currently on, immediate downloads are blocked by many browsers for user security reasons. If you use this solution, do not initiate the file download unless a user clicks on a button to intentionally download.
In order to get by this, I needed to fetch the file from the URL getting around any CORS policies to save a local Blob that would then be the source of the downloaded file. In the code below, make sure you swap in your own fileURL
, Content-Type
, and FileName
.
fetch('https://cors-anywhere.herokuapp.com/' + fileURL, {
method: 'GET',
headers: {
'Content-Type': 'application/pdf',
},
})
.then((response) => response.blob())
.then((blob) => {
// Create blob link to download
const url = window.URL.createObjectURL(
new Blob([blob]),
);
const link = document.createElement('a');
link.href = url;
link.setAttribute(
'download',
`FileName.pdf`,
);
// Append to html link element page
document.body.appendChild(link);
// Start download
link.click();
// Clean up and remove the link
link.parentNode.removeChild(link);
});
This solution references solutions to getting a blob from a URL and using a CORS proxy.
Update As of January 31st, 2021, the cors-anywhere demo hosted on Heroku servers will only allow limited use for testing purposes and cannot be used for production applications. You will have to host your own cors-anywhere server by following cors-anywhere or cors-server.
Print the stack trace to a PrintStream
, then convert it to a String
:
// ...
catch (Exception e)
{
ByteArrayOutputStream out = new ByteArrayOutputStream();
e.printStackTrace(new PrintStream(out));
String str = new String(out.toByteArray());
System.out.println(str);
}
<script type="text/javascript">
$(document).ready(function() {
$(this).attr("title", "sometitle");
});
</script>
Given that the Apache Subversion server will be moved to this new DNS alias: sub.someaddress.com.tr
:
With Subversion 1.7 or higher, use svn relocate
. Relocate is used when the SVN server's location changes. switch
is only used if you want to change your local working copy to another branch or another path. If using TortoiseSVN, you may follow instructions from the TortoiseSVN Manual. If using the SVN command line interface, refer to this section of SVN's documentation. The command should look like this:
svn relocate svn://sub.someaddress.com.tr/project
Keep using /project
given that the actual contents of your repository probably won't change.
Note: svn relocate
is not available before version 1.7 (thanks to ColinM for the info). In older versions you would use:
svn switch --relocate OLD NEW
You need to add a reference to the .NET assembly System.Data.Entity.dll.