Programs & Examples On #Runpy

FailedPreconditionError: Attempting to use uninitialized in Tensorflow

Different use case, but set your session as the default session did the trick for me:

with sess.as_default():
    result = compute_fn([seed_input,1])

This is one of these mistakes that is so obvious, once you have solved it.

My use-case is the following:
1) store keras VGG16 as tensorflow graph
2) load kers VGG16 as a graph
3) run tf function on the graph and get:

FailedPreconditionError: Attempting to use uninitialized value block1_conv2/bias
     [[Node: block1_conv2/bias/read = Identity[T=DT_FLOAT, _class=["loc:@block1_conv2/bias"], _device="/job:localhost/replica:0/task:0/device:GPU:0"](block1_conv2/bias)]]
     [[Node: predictions/Softmax/_7 = _Recv[client_terminated=false, recv_device="/job:localhost/replica:0/task:0/device:CPU:0", send_device="/job:localhost/replica:0/task:0/device:GPU:0", send_device_incarnation=1, tensor_name="edge_168_predictions/Softmax", tensor_type=DT_FLOAT, _device="/job:localhost/replica:0/task:0/device:CPU:0"]()]]

ImportError: cannot import name main when running pip --version command in windows7 32 bit

i fixed the problem by reinstalling pip using get-pip.py.

  1. Download get-pip from official link: https://pip.pypa.io/en/stable/installing/#upgrading-pip
  2. run it using commande: python get-pip.py.

And pip is fixed and work perfectly.

How to implement a confirmation (yes/no) DialogPreference?

Android comes with a built-in YesNoPreference class that does exactly what you want (a confirm dialog with yes and no options). See the official source code here.

Unfortunately, it is in the com.android.internal.preference package, which means it is a part of Android's private APIs and you cannot access it from your application (private API classes are subject to change without notice, hence the reason why Google does not let you access them).

Solution: just re-create the class in your application's package by copy/pasting the official source code from the link I provided. I've tried this, and it works fine (there's no reason why it shouldn't).

You can then add it to your preferences.xml like any other Preference. Example:

<com.example.myapp.YesNoPreference
    android:dialogMessage="Are you sure you want to revert all settings to their default values?"
    android:key="com.example.myapp.pref_reset_settings_key"
    android:summary="Revert all settings to their default values."
    android:title="Reset Settings" />

Which looks like this:

screenshot

WebForms UnobtrusiveValidationMode requires a ScriptResourceMapping for jquery

Since .NET 4.5 the Validators use data-attributes and bounded Javascript to do the validation work, so .NET expects you to add a script reference for jQuery.

There are two possible ways to solve the error:


Disable UnobtrusiveValidationMode:

Add this to web.config:

<configuration>
    <appSettings>
        <add key="ValidationSettings:UnobtrusiveValidationMode" value="None" />
    </appSettings>
</configuration>

It will work as it worked in previous .NET versions and will just add the necessary Javascript to your page to make the validators work, instead of looking for the code in your jQuery file. This is the common solution actually.


Another solution is to register the script:

In Global.asax Application_Start add mapping to your jQuery file path:

void Application_Start(object sender, EventArgs e) 
{
    // Code that runs on application startup
    ScriptManager.ScriptResourceMapping.AddDefinition("jquery", 
    new ScriptResourceDefinition
    {
        Path = "~/scripts/jquery-1.7.2.min.js",
        DebugPath = "~/scripts/jquery-1.7.2.js",
        CdnPath = "http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.1.min.js",
        CdnDebugPath = "http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.4.1.js"
    });
}

Some details from MSDN:

ValidationSettings:UnobtrusiveValidationMode Specifies how ASP.NET globally enables the built-in validator controls to use unobtrusive JavaScript for client-side validation logic.

If this key value is set to "None" [default], the ASP.NET application will use the pre-4.5 behavior (JavaScript inline in the pages) for client-side validation logic.

If this key value is set to "WebForms", ASP.NET uses HTML5 data-attributes and late bound JavaScript from an added script reference for client-side validation logic.

postgresql: INSERT INTO ... (SELECT * ...)

You can use dblink to create a view that is resolved in another database. This database may be on another server.

How do I pass multiple attributes into an Angular.js attribute directive?

If you "require" 'exampleDirective' from another directive + your logic is in 'exampleDirective's' controller (let's say 'exampleCtrl'):

app.directive('exampleDirective', function () {
    return {
        restrict: 'A',
        scope: false,
        bindToController: {
            myCallback: '&exampleFunction'
        },
        controller: 'exampleCtrl',
        controllerAs: 'vm'
    };
});
app.controller('exampleCtrl', function () {
    var vm = this;
    vm.myCallback();
});

DELETE ... FROM ... WHERE ... IN

The canonical T-SQL (SqlServer) answer is to use a DELETE with JOIN as such

DELETE o
FROM Orders o
INNER JOIN Customers c
    ON o.CustomerId = c.CustomerId
WHERE c.FirstName = 'sklivvz'

This will delete all orders which have a customer with first name Sklivvz.

How can I calculate divide and modulo for integers in C#?

Division is performed using the / operator:

result = a / b;

Modulo division is done using the % operator:

result = a % b;

How do I find out what type each object is in a ArrayList<Object>?

Since Java 8


        mixedArrayList.forEach((o) -> {
            String type = o.getClass().getSimpleName();
            switch (type) {
                case "String":
                    // treat as a String
                    break;
                case "Integer":
                    // treat as an int
                    break;
                case "Double":
                    // treat as a double
                    break;
                ...
                default:
                    // whatever
            }
        });

Using variables in Nginx location rules

A modified python version of @danack's PHP generate script. It generates all files & folders that live inside of build/ to the parent directory, replacing all {{placeholder}} matches. You need to cd into build/ before running the script.

File structure

build/
-- (files/folders you want to generate)
-- build.py

sites-available/...
sites-enabled/...
nginx.conf
...

build.py

import os, re

# Configurations
target = os.path.join('.', '..')
variables = {
  'placeholder': 'your replacement here'
}


# Loop files
def loop(cb, subdir=''):
  dir = os.path.join('.', subdir);

  for name in os.listdir(dir):
    file = os.path.join(dir, name)
    newsubdir = os.path.join(subdir, name)

    if name == 'build.py': continue
    if os.path.isdir(file): loop(cb, newsubdir)
    else: cb(subdir, name)


# Update file
def replacer(subdir, name):
  dir  = os.path.join(target, subdir)
  file = os.path.join(dir, name)
  oldfile = os.path.join('.', subdir, name)

  with open(oldfile, "r") as fin:
    data = fin.read()

  for key, replacement in variables.iteritems():
    data = re.sub(r"{{\s*" + key + "\s*}}", replacement, data)

  if not os.path.exists(dir):
    os.makedirs(dir)

  with open(file, "w") as fout:
    fout.write(data)


# Start variable replacements.
loop(replacer)

Switch with if, else if, else, and loops inside case

Seems like kind of a homely way of doing things, but if you must... you could restructure it as such to fit your needs:

boolean found = false;

case 1:

for (Element arrayItem : array) {
    if (arrayItem == whateverValue) {
        found = true;    
    } // else if ...
}
if (found) {
    break;
}
case 2:

Best way to iterate through a Perl array

  • In terms of speed: #1 and #4, but not by much in most instances.

    You could write a benchmark to confirm, but I suspect you'll find #1 and #4 to be slightly faster because the iteration work is done in C instead of Perl, and no needless copying of the array elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.)

    #5 might be similar.

  • In terms memory usage: They're all the same except for #5.

    for (@a) is special-cased to avoid flattening the array. The loop iterates over the indexes of the array.

  • In terms of readability: #1.

  • In terms of flexibility: #1/#4 and #5.

    #2 does not support elements that are false. #2 and #3 are destructive.

Commands out of sync; you can't run this command now

Create two connections, use both separately

$mysqli = new mysqli("localhost", "Admin", "dilhdk", "SMS");

$conn = new mysqli("localhost", "Admin", "dilhdk", "SMS"); 

Simple way to create matrix of random numbers

random_matrix = [[random.random for j in range(collumns)] for i in range(rows)
for i in range(rows):
    print random_matrix[i]

how to remove time from datetime

I found this method to be quite useful. However it will convert your date/time format to just date but never the less it does the job for what I need it for. (I just needed to display the date on a report, the time was irrelevant).

CAST(start_date AS DATE)

UPDATE

(Bear in mind I'm a trainee ;))

I figured an easier way to do this IF YOU'RE USING SSRS.

It's easier to actually change the textbox properties where the field is located in the report. Right click field>Number>Date and select the appropriate format!

Convert from List into IEnumerable format

You don't need to convert it. List<T> implements the IEnumerable<T> interface so it is already an enumerable.

This means that it is perfectly fine to have the following:

public IEnumerable<Book> GetBooks()
{
    List<Book> books = FetchEmFromSomewhere();    
    return books;
}

as well as:

public void ProcessBooks(IEnumerable<Book> books)
{
    // do something with those books
}

which could be invoked:

List<Book> books = FetchEmFromSomewhere();    
ProcessBooks(books);

Insert some string into given string at given index in Python

Implementation

The functions below will allow one to insert one string into another string:

def str_insert(from_me, into_me, at):
    """
    Inserts the string <from_me> into <into_me>

    Input <at> must be an integer index of <into_me> or a substring of <into_me>

    Inserts <from_me> AFTER <at>, not before <at>

    Inputs <from_me> and <into_me> must have working __str__ methods defined.
    This is satisfied if they already are strings.

    If not already strings, <from_me>, <into_me> are converted into strings.

    If you try to insert an empty string, that's fine, and the result
    is no different from the original.

    In order to insert 'from_me' after nothing (insert at the beginning of the string) use:
        at = ''  or  at = 0
    """
    try:
        return str_insert_or_raise(from_me, into_me, at)
    except ValueError as err:
        serr = str(err)
        if (str_insert_or_raise.__name__ in serr) and 'not found' in serr and '<at>' in serr:
            # if can't find where to insert stuff, don't bother to insert it
            # use str_insert_or_raise if you want an exception instead
            return into_me
        else:
            raise err

##############################################################

def str_insert_or_raise(from_me, into_me, at):
    """
    Inserts the string <from_me> into <into_me>

    Inserts <from_me> AFTER <at>, not before <at>

    Input <at> must be an integer index of <into_me> or a substring of <into_me>

    If <at> is the string '15', that substring will be searched for,
    '15' will not be interpreted as an index/subscript.        

    Inputs <from_me> and <into_me> must have working __str__ methods defined.
    If not already strings, <from_me>, <into_me> are converted into strings. 

    If you try to insert something, but we cannot find the position where
    you said to insert it, then an exception is thrown guaranteed to at least
    contain the following three substrings:
        str_insert_or_raise.__name__
        'not found'
        '<at>'
    """
    try:
        if isinstance(at, int):
            return str_insert_by_int(from_me, into_me, at)
        # Below, the calls to str() work fine if <at> and <from_me> are already strings
        # it makes them strings if they are not already
        return str_insert_by_str(str(from_me), str(into_me), str(at))
    except ValueError as err:
        serr = str(err)
        if 'empty string' in serr:
            return into_me # We allow insertion of the empty string
        elif ("<at>" in serr) and 'not found' in serr:
            msg_start = "In " + str_insert_or_raise.__name__ + ":  "
            msg = [msg_start, "\ninput ", "<at> string", " not found in ", "<into_me>",
                              "\ninput <",   str(at)  , "> not found in <", str(into_me), ">"]
            msg = ''.join(msg)
            raise ValueError(msg) from None
        else:
           raise err
#############################################################
def str_insert_by_str(from_me, into_me, at):
    """
    Inserts the string <from_me> into <into_me>

    puts 'from_me' AFTER 'at', not before 'at'
    For example,
        str_insert_or_raise(at = '2',  from_me = '0', into_me = '123')
    puts the zero after the 2, not before the 2
    The call returns '1203' not '1023'

    Throws exceptions if input arguments are not strings.

    Also, if <from_me> is empty or <at> is not a substring of <into_me> then
    an exception is raised.

    For fewer exceptions, use <str_insert_or_raise> instead.
    """
    try:
        s = into_me.replace(at, at + from_me, 1)
    except TypeError as terr: # inputs to replace are not strings
        msg_list = ['Inputs to function ', str_insert_by_str.__name__, '() must be strings']
        raise TypeError(''.join(msg_list)) from None
    # At the end of call to replace(), the '1'  indicates we will replace
    # the leftmost occurrence of <at>, instead of every occurrence of <at>
    if (s == into_me): # <at> string not found and/or <from_me> is the empty string
        msg_start = "In " + str_insert_by_str.__name__ + ":  "
        if from_me == '':
            msg = ''.join([msg_start, "attempted to insert an empty string"])
            raise ValueError(msg) from None
        raise ValueError(msg_start, "Input <at> string not found in <into_me>.",
                                    "\nUnable to determine where you want the substring inserted.") from None
    return s
##################################################
def str_insert_by_int(from_me, into_me, at):
    """
    * Inserts the string <from_me> into <into_me> at integer index <at>    
    * throws exceptions if input arguments are not strings.    
    * Also, throws an  exception if you try to insert the empty string    
    * If <at> is less than zero, <from_me> gets placed at the
      beginning of <into_me>    
    * If <at> is greater than the largest index of <into_me>,
      <from_me> gets placed after the end of <into_me>

    For fewer exceptions, use <str_insert_or_raise> instead.
    """
    at = into_me[:(at if at > 0 else 0)]
    return str_insert_by_str(from_me, into_me, at)

Usage

The code below demonstrates how to call the str_insert function given earlier

def foo(*args):
    return args

F = 'F. '

s = 'Using the string \'John \' to specify where to make the insertion'
result = str_insert(from_me = F, into_me ='John Kennedy', at ='John ')
print(foo('\n\n', s, '\n', result))

s = 'Using an int returned by find(\'Ken\') to specify where to make the insertion'
index = 'John Kennedy'.find('Ken') # returns the position of the first letter of 'Ken', not the last letter
result = str_insert(from_me = F, into_me ='John Kennedy', at = index)
print(foo('\n\n', s, '\n', result))

s = 'Using an int (5) to specify where to make the insertion.'
result = str_insert(from_me = F, into_me ='John Kennedy', at = 5)
print(foo('\n\n', s, '\n', result))

s = "Looking for an 'at' string which does not exist"
result = str_insert(from_me = F, into_me ='John Kennedy', at ='x')
print(foo('\n\n', s, '\n', result))

s = ''.join(["Looking for the empty string.",
             "\nFind one immediately at the beginning of the string"])
result = str_insert(from_me = F, into_me ='John Kennedy', at = '')
print(foo('\n\n', s, '\n', result))

s = "Insert an empty string at index 3. No visible change"
result = str_insert(from_me = '', into_me = 'John Kennedy', at = 3)
print(foo('\n\n', s, '\n', result))    

for index in [-5, -1, 0, 1, 997, 999]:
    s = "index " + str(index)
    result = str_insert(from_me = F, into_me = 'John Kennedy', at = index)
    print(foo('\n\n', s, '\n', result))

Warning About Lack of Ability to Modify In-Place

None of the functions above will modify a string "in-place." The functions each return a modified copy of the string, but the original string remains intact.

For example,

s = ''.join(["Below is what we get when we forget ",
             "to overwrite the string with the value",
             " returned by str_insert_or_raise:"])

examp_str = 'John Kennedy'
str_insert('John ', F, examp_str)
print(foo('\n\n', s, '\n', examp_str))

# examp_str is still 'John Kennedy' without the F

How to show Snackbar when Activity starts?

I have had trouble myself displaying Snackbar until now. Here is the simplest way to display a Snackbar. To display it as your Main Activity Starts, just put these two lines inside your OnCreate()

    Snackbar snackbar = Snackbar.make(findViewById(android.R.id.content), "Welcome To Main Activity", Snackbar.LENGTH_LONG);
    snackbar.show();

P.S. Just make sure you have imported the Android Design Support.(As mentioned in the question).

For Kotlin,

Snackbar.make(findViewById(android.R.id.content), message, Snackbar.LENGTH_SHORT).show()

Rotating a view in Android

You could create an animation and apply it to your button view. For example:

    // Locate view
    ImageView diskView = (ImageView) findViewById(R.id.imageView3);

    // Create an animation instance
    Animation an = new RotateAnimation(0.0f, 360.0f, pivotX, pivotY);

    // Set the animation's parameters
    an.setDuration(10000);               // duration in ms
    an.setRepeatCount(0);                // -1 = infinite repeated
    an.setRepeatMode(Animation.REVERSE); // reverses each repeat
    an.setFillAfter(true);               // keep rotation after animation

    // Aply animation to image view
    diskView.setAnimation(an);

how to fetch data from database in Hibernate

Let me quote this:

Hibernate created a new language named Hibernate Query Language (HQL), the syntax is quite similar to database SQL language. The main difference between is HQL uses class name instead of table name, and property names instead of column name.

As far as I can see you are using the table name.

So it should be like this:

Query query = session.createQuery("from Employee");

calling another method from the main method in java

Check out for the static before the main method, this declares the method as a class method, which means it needs no instance to be called. So as you are going to call a non static method, Java complains because you are trying to call a so called "instance method", which, of course needs an instance first ;)

If you want a better understanding about classes and instances, create a new class with instance and class methods, create a object in your main loop and call the methods!

 class Foo{

    public static void main(String[] args){
       Bar myInstance = new Bar();
       myInstance.do(); // works!
       Bar.do(); // doesn't work!

       Bar.doSomethingStatic(); // works!
    }
 }

class Bar{

   public do() {
   // do something
   }

   public static doSomethingStatic(){
   }
}

Also remember, classes in Java should start with an uppercase letter.

What is "Connect Timeout" in sql server connection string?

That is the timeout to create the connection, NOT a timeout for commands executed over that connection.

See for instance http://www.connectionstrings.com/all-sql-server-connection-string-keywords/ (note that the property is "Connect Timeout" (or "Connection Timeout"), not just "Timeout")


From the comments:

It is not possible to set the command timeout through the connection string. However, the SqlCommand has a CommandTimeout property (derived from DbCommand) where you can set a timeout (in seconds) per command.

Do note that when you loop over query results with Read(), the timeout is reset on every read. The timeout is for each network request, not for the total connection.

How to define a default value for "input type=text" without using attribute 'value'?

You can set the value property using client script after the element is created:

<input type="text" id="fee" />

<script type="text/javascript>
document.getElementById('fee').value = '1000';
</script>

How can I change cols of textarea in twitter-bootstrap?

The other answers didn't work for me. This did:

    <div class="span6">
      <h2>Document</h2>
        </p>
        <textarea class="field span12" id="textarea" rows="6" placeholder="Enter a short synopsis"></textarea>
        <button class="btn">Upload</button>
    </div>

Note the span12 in a div with span6.

Why does range(start, end) not include end?

Because it's more common to call range(0, 10) which returns [0,1,2,3,4,5,6,7,8,9] which contains 10 elements which equals len(range(0, 10)). Remember that programmers prefer 0-based indexing.

Also, consider the following common code snippet:

for i in range(len(li)):
    pass

Could you see that if range() went up to exactly len(li) that this would be problematic? The programmer would need to explicitly subtract 1. This also follows the common trend of programmers preferring for(int i = 0; i < 10; i++) over for(int i = 0; i <= 9; i++).

If you are calling range with a start of 1 frequently, you might want to define your own function:

>>> def range1(start, end):
...     return range(start, end+1)
...
>>> range1(1, 10)
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

Make REST API call in Swift

You can do like this :

var url : String = "http://google.com?test=toto&test2=titi"
var request : NSMutableURLRequest = NSMutableURLRequest()
request.URL = NSURL(string: url)
request.HTTPMethod = "GET"

NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue(), completionHandler:{ (response:NSURLResponse!, data: NSData!, error: NSError!) -> Void in
    var error: AutoreleasingUnsafeMutablePointer<NSError?> = nil
    let jsonResult: NSDictionary! = NSJSONSerialization.JSONObjectWithData(data, options:NSJSONReadingOptions.MutableContainers, error: error) as? NSDictionary

    if (jsonResult != nil) {
        // process jsonResult
    } else {
       // couldn't load JSON, look at error
    }


})

EDIT : For people have problem with this maybe your JSON stream is an array [] and not an object {} so you have to change jsonResult to NSArray instead of NSDictionary

What are the differences between Mustache.js and Handlebars.js?

Another difference between them is the size of the file:

To see the performance benefits of Handlebars.js we must use precompiled templates.

Source: An Overview of JavaScript Templating Engines

What's the UIScrollView contentInset property for?

It's used to add padding in UIScrollView

Without contentInset, a table view is like this:

enter image description here

Then set contentInset:

tableView.contentInset = UIEdgeInsets(top: 20, left: 0, bottom: 0, right: 0)

The effect is as below:

enter image description here

Seems to be better, right?

And I write a blog to study the contentInset, criticism is welcome.

Append text using StreamWriter

Also look at log4net, which makes logging to 1 or more event stores — whether it's the console, the Windows event log, a text file, a network pipe, a SQL database, etc. — pretty trivial. You can even filter stuff in its configuration, for instance, so that only log records of a particular severity (say ERROR or FATAL) from a single component or assembly are directed to a particular event store.

http://logging.apache.org/log4net/

How can I perform a short delay in C# without using sleep?

Sorry for awakening an old question like this. But I think what the original author wanted as an answer was:

You need to force your program to make the graphic update after you make the change to the textbox1. You can do that by invoking Update();

textBox1.Text += "\r\nThread Sleeps!";
textBox1.Update();
System.Threading.Thread.Sleep(4000);
textBox1.Text += "\r\nThread awakens!";
textBox1.Update();

Normally this will be done automatically when the thread is done. Ex, you press a button, changes are made to the text, thread dies, and then .Update() is fired and you see the changes. (I'm not an expert so I cant really tell you when its fired, but its something similar to this any way.)

In this case, you make a change, pause the thread, and then change the text again, and when the thread finally dies the .Update() is fired. This resulting in you only seeing the last change made to the text.

You would experience the same issue if you had a long execution between the text changes.

What is the recommended way to delete a large number of items from DynamoDB?

What I ideally want to do is call LogTable.DeleteItem(user_id) - Without supplying the range, and have it delete everything for me.

An understandable request indeed; I can imagine advanced operations like these might get added over time by the AWS team (they have a history of starting with a limited feature set first and evaluate extensions based on customer feedback), but here is what you should do to avoid the cost of a full scan at least:

  1. Use Query rather than Scan to retrieve all items for user_id - this works regardless of the combined hash/range primary key in use, because HashKeyValue and RangeKeyCondition are separate parameters in this API and the former only targets the Attribute value of the hash component of the composite primary key..

    • Please note that you''ll have to deal with the query API paging here as usual, see the ExclusiveStartKey parameter:

      Primary key of the item from which to continue an earlier query. An earlier query might provide this value as the LastEvaluatedKey if that query operation was interrupted before completing the query; either because of the result set size or the Limit parameter. The LastEvaluatedKey can be passed back in a new query request to continue the operation from that point.

  2. Loop over all returned items and either facilitate DeleteItem as usual

    • Update: Most likely BatchWriteItem is more appropriate for a use case like this (see below for details).

Update

As highlighted by ivant, the BatchWriteItem operation enables you to put or delete several items across multiple tables in a single API call [emphasis mine]:

To upload one item, you can use the PutItem API and to delete one item, you can use the DeleteItem API. However, when you want to upload or delete large amounts of data, such as uploading large amounts of data from Amazon Elastic MapReduce (EMR) or migrate data from another database in to Amazon DynamoDB, this API offers an efficient alternative.

Please note that this still has some relevant limitations, most notably:

  • Maximum operations in a single request — You can specify a total of up to 25 put or delete operations; however, the total request size cannot exceed 1 MB (the HTTP payload).

  • Not an atomic operation — Individual operations specified in a BatchWriteItem are atomic; however BatchWriteItem as a whole is a "best-effort" operation and not an atomic operation. That is, in a BatchWriteItem request, some operations might succeed and others might fail. [...]

Nevertheless this obviously offers a potentially significant gain for use cases like the one at hand.

In Visual Studio C++, what are the memory allocation representations?

This link has more information:

https://en.wikipedia.org/wiki/Magic_number_(programming)#Debug_values

* 0xABABABAB : Used by Microsoft's HeapAlloc() to mark "no man's land" guard bytes after allocated heap memory
* 0xABADCAFE : A startup to this value to initialize all free memory to catch errant pointers
* 0xBAADF00D : Used by Microsoft's LocalAlloc(LMEM_FIXED) to mark uninitialised allocated heap memory
* 0xBADCAB1E : Error Code returned to the Microsoft eVC debugger when connection is severed to the debugger
* 0xBEEFCACE : Used by Microsoft .NET as a magic number in resource files
* 0xCCCCCCCC : Used by Microsoft's C++ debugging runtime library to mark uninitialised stack memory
* 0xCDCDCDCD : Used by Microsoft's C++ debugging runtime library to mark uninitialised heap memory
* 0xDDDDDDDD : Used by Microsoft's C++ debugging heap to mark freed heap memory
* 0xDEADDEAD : A Microsoft Windows STOP Error code used when the user manually initiates the crash.
* 0xFDFDFDFD : Used by Microsoft's C++ debugging heap to mark "no man's land" guard bytes before and after allocated heap memory
* 0xFEEEFEEE : Used by Microsoft's HeapFree() to mark freed heap memory

What does the question mark operator mean in Ruby?

It may be worth pointing out that ?s are only allowed in method names, not variables. In the process of learning Ruby, I assumed that ? designated a boolean return type so I tried adding them to flag variables, leading to errors. This led to me erroneously believing for a while that there was some special syntax involving ?s.

Relevant: Why can't a variable name end with `?` while a method name can?

How to set cursor position in EditText?

I want to set cursor position in edittext which contains no data

There is only one position in an empty EditText, it's setSelection(0).

Or did you mean you want to get focus to your EditText when your activity opens? In that case its requestFocus()

How to add a WiX custom action that happens only on uninstall (via MSI)?

You can do this with a custom action. You can add a refrence to your custom action under <InstallExecuteSequence>:

<InstallExecuteSequence>
...
  <Custom Action="FileCleaner" After='InstallFinalize'>
          Installed AND NOT UPGRADINGPRODUCTCODE</Custom>

Then you will also have to define your Action under <Product>:

<Product> 
...
  <CustomAction Id='FileCleaner' BinaryKey='FileCleanerEXE' 
                ExeCommand='' Return='asyncNoWait'  />

Where FileCleanerEXE is a binary (in my case a little c++ program that does the custom action) which is also defined under <Product>:

<Product> 
...
  <Binary Id="FileCleanerEXE" SourceFile="path\to\fileCleaner.exe" />

The real trick to this is the Installed AND NOT UPGRADINGPRODUCTCODE condition on the Custom Action, with out that your action will get run on every upgrade (since an upgrade is really an uninstall then reinstall). Which if you are deleting files is probably not want you want during upgrading.

On a side note: I recommend going through the trouble of using something like C++ program to do the action, instead of a batch script because of the power and control it provides -- and you can prevent the "cmd prompt" window from flashing while your installer runs.

What are ABAP and SAP?

I have worked with SAP since 1998. SAP is a type of software called ERP (Enterprise Resource Planning) that large companies use to manage their day to day affairs. On the macro, the software can be split into two categories: Technical and Functional

Let's go Technical first, as it answers the "What is ABAP" part of your question.

Technical

There are two technical "stacks" within the SAP software, the first is the ABAP stack which is inclusive of all the original technology that SAP was. ABAP is the proprietary coding language for SAP to develop RICEFW objects (Reports, Interfaces, Conversions, Extensions, Forms and Workflows) within the ABAP stack.

The ABAP stack is traditionally navigated via Transaction Codes (T-Codes) to take you to different screens within the SAP Environment. From a technical perspective, you will do all of your performance and tuning of the WORK PROCESSES in the SAP system here, as well as configuring all of the system RFCs, building user profiles and also doing the necessary interfacing between the OS (usually Windows or HPUX) and the Oracle Database (currently Enterprise 11g).

The JAVA stack controls the "Netweaver" aspect of SAP which encapsulates SAP's ability to be accessed via the Internet via SAP Portal and it's ability to interface with other SAP and non-SAP legacy systems via Process Integration (PI).

SAP also has extensive capabilities in the Business Intelligence Field (BI) by accessing information stored within the Business Warehouse (BW). Currently, there is a new technology called HANA 1.0 that compresses the time to run reports against these repositories.

There are two primarily technologists that run ALL of these functions, they are called SAP Basis (Netweaver) Administrators and ABAP Developers.

Functional

SAP has specific pre-populated functional packages for different business areas. For example, Exxon runs the "IS Oil & Gas" package while Bank of America runs the "Banking" package, while further still Lockheed Martin runs the "Aerospace & Defense" package. These packages were developed over time by the amalgamation of intelligent functional customizations that could be intelligently ported to the system via inclusion in dot releases.

However, there are some vanilla functional modules that almost all entities run, regardless of their specific industry:

  • HR: Human Resources
  • PM: Project Management
  • FI: Financial
  • CO: Controllers
  • MM: Materials Management
  • SD: Sales and Distribution
  • PP: Production Planning

and finally the biggie:

  • MDM: Master Data Management which encapsulates the data for customer/vendor/material etc.

Storing Images in PostgreSQL

In the database, there are two options:

  • bytea. Stores the data in a column, exported as part of a backup. Uses standard database functions to save and retrieve. Recommended for your needs.
  • blobs. Stores the data externally, not normally exported as part of a backup. Requires special database functions to save and retrieve.

I've used bytea columns with great success in the past storing 10+gb of images with thousands of rows. PG's TOAST functionality pretty much negates any advantage that blobs have. You'll need to include metadata columns in either case for filename, content-type, dimensions, etc.

Make a Bash alias that takes a parameter?

For taking parameters, you should use functions!

However $@ get interpreted when creating the alias instead of during the execution of the alias and escaping the $ doesn’t work either. How do I solve this problem?

You need to use shell function instead of an alias to get rid of this problem. You can define foo as follows:

function foo() { /path/to/command "$@" ;}

OR

foo() { /path/to/command "$@" ;}

Finally, call your foo() using the following syntax:

foo arg1 arg2 argN

Make sure you add your foo() to ~/.bash_profile or ~/.zshrc file.

In your case, this will work

function trash() { mv $@ ~/.Trash; }

Escape curly brace '{' in String.Format

Use double braces {{ or }} so your code becomes:

sb.AppendLine(String.Format("public {0} {1} {{ get; private set; }}", 
prop.Type, prop.Name));

// For prop.Type of "Foo" and prop.Name of "Bar", the result would be:
// public Foo Bar { get; private set; }

A quick and easy way to join array elements with a separator (the opposite of split) in Java

public String join(String[] str, String separator){
    String retval = "";
    for (String s: str){ retval+= separator + s;}
    return retval.replaceFirst(separator, "");
}

Make an HTTP request with android

UPDATE

This is a very old answer. I definitely won't recommend Apache's client anymore. Instead use either:

Original Answer

First of all, request a permission to access network, add following to your manifest:

<uses-permission android:name="android.permission.INTERNET" />

Then the easiest way is to use Apache http client bundled with Android:

    HttpClient httpclient = new DefaultHttpClient();
    HttpResponse response = httpclient.execute(new HttpGet(URL));
    StatusLine statusLine = response.getStatusLine();
    if(statusLine.getStatusCode() == HttpStatus.SC_OK){
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        response.getEntity().writeTo(out);
        String responseString = out.toString();
        out.close();
        //..more logic
    } else{
        //Closes the connection.
        response.getEntity().getContent().close();
        throw new IOException(statusLine.getReasonPhrase());
    }

If you want it to run on separate thread I'd recommend extending AsyncTask:

class RequestTask extends AsyncTask<String, String, String>{

    @Override
    protected String doInBackground(String... uri) {
        HttpClient httpclient = new DefaultHttpClient();
        HttpResponse response;
        String responseString = null;
        try {
            response = httpclient.execute(new HttpGet(uri[0]));
            StatusLine statusLine = response.getStatusLine();
            if(statusLine.getStatusCode() == HttpStatus.SC_OK){
                ByteArrayOutputStream out = new ByteArrayOutputStream();
                response.getEntity().writeTo(out);
                responseString = out.toString();
                out.close();
            } else{
                //Closes the connection.
                response.getEntity().getContent().close();
                throw new IOException(statusLine.getReasonPhrase());
            }
        } catch (ClientProtocolException e) {
            //TODO Handle problems..
        } catch (IOException e) {
            //TODO Handle problems..
        }
        return responseString;
    }
    
    @Override
    protected void onPostExecute(String result) {
        super.onPostExecute(result);
        //Do anything with response..
    }
}

You then can make a request by:

   new RequestTask().execute("http://stackoverflow.com");

Requests -- how to tell if you're getting a 404

Look at the r.status_code attribute:

if r.status_code == 404:
    # A 404 was issued.

Demo:

>>> import requests
>>> r = requests.get('http://httpbin.org/status/404')
>>> r.status_code
404

If you want requests to raise an exception for error codes (4xx or 5xx), call r.raise_for_status():

>>> r = requests.get('http://httpbin.org/status/404')
>>> r.raise_for_status()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "requests/models.py", line 664, in raise_for_status
    raise http_error
requests.exceptions.HTTPError: 404 Client Error: NOT FOUND
>>> r = requests.get('http://httpbin.org/status/200')
>>> r.raise_for_status()
>>> # no exception raised.

You can also test the response object in a boolean context; if the status code is not an error code (4xx or 5xx), it is considered ‘true’:

if r:
    # successful response

If you want to be more explicit, use if r.ok:.

How can I format the output of a bash command in neat columns

While awk's printf can be used, you may want to look into pr or (on BSDish systems) rs for formatting.

This IP, site or mobile application is not authorized to use this API key

I had the same issue and I found this.

On the url, it requires the server key in the end and not the api key for the app.

So Basically, you just add the server key in the end of the URL like this:

https://maps.googleapis.com/maps/api/place/nearbysearch/json?location=yourlatitude,yourlongitude&radius=5000&sensor=true&key=SERVERKEY

Now, to obtain the server key, just follow these steps:

1) Go to Developer Console https://code.google.com/apis/console/

2) In the Credentials, under Public API Access, Create New key

3) Select the server key from the option.

4) Enter your IP Address on the field and if you have more ip addresses, you can just add on every single line.NOTE: Enter the IP Address only when you want to use it for your testing purpose. Else leave the IP Address section blank.

5) Once you are done, click create and your new Server Key will be generated and you can then add that server key to your URL.

Last thing is that, instead of putting the sensor=true in the middle of the URL, you can add it in the end like this:

https://maps.googleapis.com/maps/api/place/nearbysearch/json?location=yourlatitude,yourlongitude&radius=5000&key=SERVERKEY&sensor=true

This will definitely solve the issue and just remember to use the server key for Places API.

EDIT

I believe the web URL has changed in the past years. You can access developers console from here now - https://console.developers.google.com/apis/dashboard

  • Navigate to developers console - https://console.developers.google.com/ or use the link from details to navigate directly to API dashboard.
  • Under developer console, find Label from the left navigation panel
  • Select project
  • Choose Credentials from the left Navigation panel
  • You could create credentials type from the Top nav bar as required.

Hope this answer will help you and other viewers. Good Luck .. :)

How to display multiple notifications in android

Another way of doing it is take the current date convert it into long just take the last 4 digits. There is a high probability that the number will be unique.

    long time = new Date().getTime();
    String tmpStr = String.valueOf(time);
    String last4Str = tmpStr.substring(tmpStr.length() -5);
    int notificationId = Integer.valueOf(last4Str);

Does mobile Google Chrome support browser extensions?

I imagine that there are not many browsers supporting extension. Indeed, I have been interested in this question for the last year and I only found Dolphin supporting add-ons and other cool features announced few days ago. I want to test it soon.

Eclipse: How to install a plugin manually?

  1. Download your plugin
  2. Open Eclipse
  3. From the menu choose: Help / Install New Software...
  4. Click the Add button
  5. In the Add Repository dialog that appears, click the Archive button next to the Location field
  6. Select your plugin file, click OK

You could also just copy plugins to the eclipse/plugins directory, but it's not recommended.

The model item passed into the dictionary is of type .. but this dictionary requires a model item of type

This question already has a great answer, but I ran into the same error, in a different scenario: displaying a List in an EditorTemplate.

I have a model like this:

public class Foo
{
    public string FooName { get; set; }
    public List<Bar> Bars { get; set; }
}

public class Bar
{
    public string BarName { get; set; }
}

And this is my main view:

@model Foo

@Html.TextBoxFor(m => m.Name, new { @class = "form-control" })  
@Html.EditorFor(m => m.Bars)

And this is my Bar EditorTemplate (Bar.cshtml)

@model List<Bar>

<div class="some-style">
    @foreach (var item in Model)
    {
        <label>@item.BarName</label>
    }
</div>

And I got this error:

The model item passed into the dictionary is of type 'Bar', but this dictionary requires a model item of type 'System.Collections.Generic.List`1[Bar]


The reason for this error is that EditorFor already iterates the List for you, so if you pass a collection to it, it would display the editor template once for each item in the collection.

This is how I fixed this problem:

Brought the styles outside of the editor template, and into the main view:

@model Foo

@Html.TextBoxFor(m => m.Name, new { @class = "form-control" })  
<div class="some-style">
    @Html.EditorFor(m => m.Bars)
</div>

And changed the EditorTemplate (Bar.cshtml) to this:

@model Bar

<label>@Model.BarName</label>

How to get correct timestamp in C#

var Timestamp = new DateTimeOffset(DateTime.UtcNow).ToUnixTimeSeconds();

How do I specify different Layouts in the ASP.NET MVC 3 razor ViewStart file?

This method is the simplest way for beginners to control Layouts rendering in your ASP.NET MVC application. We can identify the controller and render the Layouts as par controller, to do this we can write our code in _ViewStart file in the root directory of the Views folder. Following is an example shows how it can be done.

@{
    var controller = HttpContext.Current.Request.RequestContext.RouteData.Values["Controller"].ToString();
    string cLayout = "";

    if (controller == "Webmaster")
        cLayout = "~/Views/Shared/_WebmasterLayout.cshtml";
    else
        cLayout = "~/Views/Shared/_Layout.cshtml";

    Layout = cLayout;
}

Read Complete Article here "How to Render different Layout in ASP.NET MVC"

How Does Modulus Divison Work

Write out a table starting with 0.

{0,1,2,3,4}

Continue the table in rows.

{0,1,2,3,4}
{5,6,7,8,9}
{10,11,12,13,14}

Everything in column one is a multiple of 5. Everything in column 2 is a multiple of 5 with 1 as a remainder. Now the abstract part: You can write that (1) as 1/5 or as a decimal expansion. The modulus operator returns only the column, or in another way of thinking, it returns the remainder on long division. You are dealing in modulo(5). Different modulus, different table. Think of a Hash Table.

Alternative for PHP_excel

I wrote a very simple class for exporting to "Excel XML" aka SpreadsheetML. It's not quite as convenient for the end user as XSLX (depending on file extension and Excel version, they may get a warning message), but it's a lot easier to work with than XLS or XLSX.

http://github.com/elidickinson/php-export-data

Test if remote TCP port is open from a shell script

I needed a more flexible solution for working on multiple git repositories so I wrote the following sh code based on 1 and 2. You can use your server address instead of gitlab.com and your port in replace of 22.

SERVER=gitlab.com
PORT=22
nc -z -v -w5 $SERVER $PORT
result1=$?

#Do whatever you want

if [  "$result1" != 0 ]; then
  echo  'port 22 is closed'
else
  echo 'port 22 is open'
fi

Retaining file permissions with Git

Git is Version Control System, created for software development, so from the whole set of modes and permissions it stores only executable bit (for ordinary files) and symlink bit. If you want to store full permissions, you need third party tool, like git-cache-meta (mentioned by VonC), or Metastore (used by etckeeper). Or you can use IsiSetup, which IIRC uses git as backend.

See Interfaces, frontends, and tools page on Git Wiki.

Adding two numbers concatenates them instead of calculating the sum

This won't sum up the number; instead it will concatenate it:

var x = y + z;

You need to do:

var x = (y)+(z);

You must use parseInt in order to specify the operation on numbers. Example:

var x = parseInt(y) + parseInt(z); [final soulution, as everything us]

Simplest way to set image as JPanel background

Simplest way to set image as JPanel background

Don't use a JPanel. Just use a JLabel with an Icon then you don't need custom code.

See Background Panel for more information as well as a solution that will paint the image on a JPanel with 3 different painting options:

  1. scaled
  2. tiled
  3. actual

Jenkins Host key verification failed

As for the workaround (e.g. Windows slave), define the following environment variable in global properties:

GIT_SSH_COMMAND="ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no"

Jenkins, Global properties, Environment variables, GIT_SSH_COMMAND

Note: If you don't see the option, you probably need EnvInject plugin for it.

Java: how to represent graphs?

When learning algorithms, the programming language (Java) should not be considered in deciding the representation. Each problem could benefit from a unique representation, and moreover designing it can add a bit of learning. Solve the problem first without relying on a particular language, then the representation for any particular language will flow naturally.

Of course, general representations and libraries are useful in real-world applications. But some of them could benefit from some customization as well. Use the other answers to know the different techniques available, but consider customization when appropriate.

Expand a random range from 1–5 to 1–7

Simple and efficient:

int rand7 ( void )
{
    return 4; // this number has been calculated using
              // rand5() and is in the range 1..7
}

(Inspired by What's your favorite "programmer" cartoon?).

Simple prime number generator in Python

Similar to user107745, but using 'all' instead of double negation (a little bit more readable, but I think same performance):

import math
[x for x in xrange(2,10000) if all(x%t for t in xrange(2,int(math.sqrt(x))+1))]

Basically it iterates over the x in range of (2, 100) and picking only those that do not have mod == 0 for all t in range(2,x)

Another way is probably just populating the prime numbers as we go:

primes = set()
def isPrime(x):
  if x in primes:
    return x
  for i in primes:
    if not x % i:
      return None
  else:
    primes.add(x)
    return x

filter(isPrime, range(2,10000))

How do I prevent site scraping?

Most have been already said, but have you considered the CloudFlare protection? I mean this:

image description

Other companies probably do this too, CloudFlare is the only one I know.

I'm pretty sure that would complicate their work. I also once got IP banned automatically for 4 months when I tried to scrap data of a site protected by CloudFlare due to rate limit (I used simple AJAX request loop).

How to convert an integer to a character array using C

You may give a shot at using itoa. Another alternative is to use sprintf.

read word by word from file in C++

what you are doing here is reading one character at a time from the input stream and assume that all the characters between " " represent a word. BUT it's unlikely to be a " " after the last word, so that's probably why it does not work:

"word1 word2 word2EOF"

How to get the python.exe location programmatically?

This works in Linux & Windows:

Python 3.x

>>> import sys
>>> print(sys.executable)
C:\path\to\python.exe

Python 2.x

>>> import sys
>>> print sys.executable
/usr/bin/python

PHP error: Notice: Undefined index:

You're attempting to access indicies within an array which are not set. This raises a notice.

Mostly likely you're noticing it now because your code has moved to a server where php.ini has error_reporting set to include E_NOTICE. Either suppress notices by setting error_reporting to E_ALL & ~E_NOTICE (not recommended), or verify that the index exists before you attempt to access it:

$month = array_key_exists('month', $_POST) ? $_POST['month'] : null;

How to build and run Maven projects after importing into Eclipse IDE

I would recommend you don't use the m2eclipse command line tools (i.e. mvn eclipse:eclipse) and instead use the built-in Maven support, known as m2e.

Delete your project from Eclipse, then run mvn eclipse:clean on your project to remove the m2eclipse project data. Finally, with a modern version of Eclipse, just do "Import > Maven > Existing project into workspace..." and select your pom.xml.

M2e will automatically manage your dependencies and download them as required. It also supports Maven builds through a new "Run as Maven build..." interface. It's rather nifty.

Writing outputs to log file and console

I wanted to display logs on stdout and log file along with the timestamp. None of the above answers worked for me. I made use of process substitution and exec command and came up with the following code. Sample logs:

2017-06-21 11:16:41+05:30 Fetching information about files in the directory...

Add following lines at the top of your script:

LOG_FILE=script.log
exec > >(while read -r line; do printf '%s %s\n' "$(date --rfc-3339=seconds)" "$line" | tee -a $LOG_FILE; done)
exec 2> >(while read -r line; do printf '%s %s\n' "$(date --rfc-3339=seconds)" "$line" | tee -a $LOG_FILE; done >&2)

Hope this helps somebody!

Populating a ListView using an ArrayList?

Here's an example of how you could implement a list view:

 @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    //We have our list view
    final ListView dynamic = findViewById(R.id.dynamic);

    //Create an array of elements
    final ArrayList<String> classes = new ArrayList<>();
    classes.add("Data Structures");
    classes.add("Assembly Language");
    classes.add("Calculus 3");
    classes.add("Switching Systems");
    classes.add("Analysis Tools");

    //Create adapter for ArrayList
    final ArrayAdapter<String> adapter = new ArrayAdapter<>(this,android.R.layout.simple_list_item_1, classes);

    //Insert Adapter into List
    dynamic.setAdapter(adapter);

    //set click functionality for each list item
    dynamic.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            Log.i("User clicked ", classes.get(position));
        }
    });



}

Adb Devices can't find my phone

I have a ZTE Crescent phone (Orange San Francisco II).

When I connect the phone to the USB a disk shows up in OS X named 'ZTE_USB_Driver'.

Running adb devices displays no connected devices. But after I eject the 'ZTE_USB_Driver' disk from OS X, and run adb devices again the phone shows up as connected.

Display the current time and date in an Android application

SimpleDateFormat format = new SimpleDateFormat("dd/MM/yyyy");
Calendar c = Calendar.getInstance();
Date date = Calendar.getInstance().getTime();
String sDate = format.format(date);//31-12-9999
int mYear = c.get(Calendar.YEAR);//9999
int mMonth = c.get(Calendar.MONTH);
mMonth = mMonth + 1;//12
int hrs = c.get(Calendar.HOUR_OF_DAY);//24
int min = c.get(Calendar.MINUTE);//59
String AMPM;
if (c.get(Calendar.AM_PM) == 0) {
    AMPM = "AM";
} else {
    AMPM = "PM";
}

Apache POI Excel - how to configure columns to be expanded?

You can use setColumnWidth() if you want to expand your cell more.

Cannot delete directory with Directory.Delete(path, true)

I resolved one possible instance of the stated problem when methods were async and coded like this:

// delete any existing update content folder for this update
if (await fileHelper.DirectoryExistsAsync(currentUpdateFolderPath))
       await fileHelper.DeleteDirectoryAsync(currentUpdateFolderPath);

With this:

bool exists = false;                
if (await fileHelper.DirectoryExistsAsync(currentUpdateFolderPath))
    exists = true;

// delete any existing update content folder for this update
if (exists)
    await fileHelper.DeleteDirectoryAsync(currentUpdateFolderPath);

Conclusion? There is some asynchronous aspect of getting rid of the handle used to check existence that Microsoft has not been able to speak to. It's as if the asynchronous method inside an if statement has the if statement acting like a using statement.

Generating combinations in c++

A simple way using std::next_permutation:

#include <iostream>
#include <algorithm>
#include <vector>

int main() {
    int n, r;
    std::cin >> n;
    std::cin >> r;

    std::vector<bool> v(n);
    std::fill(v.end() - r, v.end(), true);

    do {
        for (int i = 0; i < n; ++i) {
            if (v[i]) {
                std::cout << (i + 1) << " ";
            }
        }
        std::cout << "\n";
    } while (std::next_permutation(v.begin(), v.end()));
    return 0;
}

or a slight variation that outputs the results in an easier to follow order:

#include <iostream>
#include <algorithm>
#include <vector>

int main() {
   int n, r;
   std::cin >> n;
   std::cin >> r;

   std::vector<bool> v(n);
   std::fill(v.begin(), v.begin() + r, true);

   do {
       for (int i = 0; i < n; ++i) {
           if (v[i]) {
               std::cout << (i + 1) << " ";
           }
       }
       std::cout << "\n";
   } while (std::prev_permutation(v.begin(), v.end()));
   return 0;
}

A bit of explanation:

It works by creating a "selection array" (v), where we place r selectors, then we create all permutations of these selectors, and print the corresponding set member if it is selected in in the current permutation of v.


You can implement it if you note that for each level r you select a number from 1 to n.

In C++, we need to 'manually' keep the state between calls that produces results (a combination): so, we build a class that on construction initialize the state, and has a member that on each call returns the combination while there are solutions: for instance

#include <iostream>
#include <iterator>
#include <vector>
#include <cstdlib>

using namespace std;

struct combinations
{
    typedef vector<int> combination_t;

    // initialize status
   combinations(int N, int R) :
       completed(N < 1 || R > N),
       generated(0),
       N(N), R(R)
   {
       for (int c = 1; c <= R; ++c)
           curr.push_back(c);
   }

   // true while there are more solutions
   bool completed;

   // count how many generated
   int generated;

   // get current and compute next combination
   combination_t next()
   {
       combination_t ret = curr;

       // find what to increment
       completed = true;
       for (int i = R - 1; i >= 0; --i)
           if (curr[i] < N - R + i + 1)
           {
               int j = curr[i] + 1;
               while (i <= R-1)
                   curr[i++] = j++;
               completed = false;
               ++generated;
               break;
           }

       return ret;
   }

private:

   int N, R;
   combination_t curr;
};

int main(int argc, char **argv)
{
    int N = argc >= 2 ? atoi(argv[1]) : 5;
    int R = argc >= 3 ? atoi(argv[2]) : 2;
    combinations cs(N, R);
    while (!cs.completed)
    {
        combinations::combination_t c = cs.next();
        copy(c.begin(), c.end(), ostream_iterator<int>(cout, ","));
        cout << endl;
    }
    return cs.generated;
}

test output:

1,2,
1,3,
1,4,
1,5,
2,3,
2,4,
2,5,
3,4,
3,5,
4,5,

How do I calculate percentiles with python/numpy?

import numpy as np
a = [154, 400, 1124, 82, 94, 108]
print np.percentile(a,95) # gives the 95th percentile

Why do we use Base64?

Media that is designed for textual data is of course eventually binary as well, but textual media often use certain binary values for control characters. Also, textual media may reject certain binary values as non-text.

Base64 encoding encodes binary data as values that can only be interpreted as text in textual media, and is free of any special characters and/or control characters, so that the data will be preserved across textual media as well.

Getting Access Denied when calling the PutObject operation with bucket-level permission

I was just banging my head against a wall just trying to get S3 uploads to work with large files. Initially my error was:

An error occurred (AccessDenied) when calling the CreateMultipartUpload operation: Access Denied

Then I tried copying a smaller file and got:

An error occurred (AccessDenied) when calling the PutObject operation: Access Denied

I could list objects fine but I couldn't do anything else even though I had s3:* permissions in my Role policy. I ended up reworking the policy to this:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:PutObject",
                "s3:GetObject",
                "s3:DeleteObject"
            ],
            "Resource": "arn:aws:s3:::my-bucket/*"
        },
        {
            "Effect": "Allow",
            "Action": [
                "s3:ListBucketMultipartUploads",
                "s3:AbortMultipartUpload",
                "s3:ListMultipartUploadParts"
            ],
            "Resource": [
                "arn:aws:s3:::my-bucket",
                "arn:aws:s3:::my-bucket/*"
            ]
        },
        {
            "Effect": "Allow",
            "Action": "s3:ListBucket",
            "Resource": "*"
        }
    ]
}

Now I'm able to upload any file. Replace my-bucket with your bucket name. I hope this helps somebody else that's going thru this.

Java: How to Indent XML Generated by Transformer

If you want the indentation, you have to specify it to the TransformerFactory.

TransformerFactory tf = TransformerFactory.newInstance();
tf.setAttribute("indent-number", new Integer(2));
Transformer t = tf.newTransformer();

Do standard windows .ini files allow comments?

USE A SEMI-COLON AT BEGINING OF LINE --->> ; <<---

Ex.

; last modified 1 April 2001 by John Doe
[owner]
name=John Doe
organization=Acme Widgets Inc.

Disable cross domain web security in Firefox

Check out my addon that works with the latest Firefox version, with beautiful UI and support JS regex: https://addons.mozilla.org/en-US/firefox/addon/cross-domain-cors

Update: I just add Chrome extension for this https://chrome.google.com/webstore/detail/cross-domain-cors/mjhpgnbimicffchbodmgfnemoghjakai

enter image description here

Git merge reports "Already up-to-date" though there is a difference

Silly but it might happen. Suppose your branch name is prefixed with an issue reference (for example #91-fix-html-markup), if you do this merge:

$ git merge #91-fix-html-markup

it will not work as intended because everything after the # is ignored, because # starts an inline comment.

In this case you can rename the branch omitting # or use single quotes to surround the branch name: git merge '#91-fix-html-markup'.

Check if an object exists

Since filter returns a QuerySet, you can use count to check how many results were returned. This is assuming you don't actually need the results.

num_results = User.objects.filter(email = cleaned_info['username']).count()

After looking at the documentation though, it's better to just call len on your filter if you are planning on using the results later, as you'll only be making one sql query:

A count() call performs a SELECT COUNT(*) behind the scenes, so you should always use count() rather than loading all of the record into Python objects and calling len() on the result (unless you need to load the objects into memory anyway, in which case len() will be faster).

num_results = len(user_object)

UIButton: set image for selected-highlighted state

In Swift 3.x, you can set highlighted image when button is selected in the following way:

// Normal state
button.setImage(UIImage(named: "normalImage"), for: .normal) 

// Highlighted state (before button is selected)
button.setImage(UIImage(named: "pressedImage"), for: .highlighted)

// Selected state
button.setImage(UIImage(named: "selectedImage"), for:  .selected)

// Highlighted state (after button is selected)
button.setImage(UIImage(named: "pressedAfterBeingSelectedImage"), 
                for:  UIControlState.selected.union(.highlighted))

Adding 'serial' to existing column in Postgres

Look at the following commands (especially the commented block).

DROP TABLE foo;
DROP TABLE bar;

CREATE TABLE foo (a int, b text);
CREATE TABLE bar (a serial, b text);

INSERT INTO foo (a, b) SELECT i, 'foo ' || i::text FROM generate_series(1, 5) i;
INSERT INTO bar (b) SELECT 'bar ' || i::text FROM generate_series(1, 5) i;

-- blocks of commands to turn foo into bar
CREATE SEQUENCE foo_a_seq;
ALTER TABLE foo ALTER COLUMN a SET DEFAULT nextval('foo_a_seq');
ALTER TABLE foo ALTER COLUMN a SET NOT NULL;
ALTER SEQUENCE foo_a_seq OWNED BY foo.a;    -- 8.2 or later

SELECT MAX(a) FROM foo;
SELECT setval('foo_a_seq', 5);  -- replace 5 by SELECT MAX result

INSERT INTO foo (b) VALUES('teste');
INSERT INTO bar (b) VALUES('teste');

SELECT * FROM foo;
SELECT * FROM bar;

How can I create a dynamically sized array of structs?

Another option for you is a linked list. You'll need to analyze how your program will use the data structure, if you don't need random access it could be faster than reallocating.

Access nested dictionary items via a list of keys?

Very late to the party, but posting in case this may help someone in the future. For my use case, the following function worked the best. Works to pull any data type out of dictionary

dict is the dictionary containing our value

list is a list of "steps" towards our value

def getnestedvalue(dict, list):

    length = len(list)
    try:
        for depth, key in enumerate(list):
            if depth == length - 1:
                output = dict[key]
                return output
            dict = dict[key]
    except (KeyError, TypeError):
        return None

    return None

Generate sha256 with OpenSSL and C++

I think that you only have to replace SHA1 function with SHA256 function with tatk code from link in Your post

Multi-dimensional arraylist or list in C#?

you just make a list of lists like so:

List<List<string>> results = new List<List<string>>();

and then it's just a matter of using the functionality you want

results.Add(new List<string>()); //adds a new list to your list of lists
results[0].Add("this is a string"); //adds a string to the first list
results[0][0]; //gets the first string in your first list

stdlib and colored output in C

#include <stdio.h>

#define BLUE(string) "\x1b[34m" string "\x1b[0m"
#define RED(string) "\x1b[31m" string "\x1b[0m"

int main(void)
{
    printf("this is " RED("red") "!\n");

    // a somewhat more complex ...
    printf("this is " BLUE("%s") "!\n","blue");

    return 0;
}

reading Wikipedia:

  • \x1b[0m resets all attributes
  • \x1b[31m sets foreground color to red
  • \x1b[44m would set the background to blue.
  • both : \x1b[31;44m
  • both but inversed : \x1b[31;44;7m
  • remember to reset afterwards \x1b[0m ...

java howto ArrayList push, pop, shift, and unshift

I was facing with this problem some time ago and I found java.util.LinkedList is best for my case. It has several methods, with different namings, but they're doing what is needed:

push()    -> LinkedList.addLast(); // Or just LinkedList.add();
pop()     -> LinkedList.pollLast();
shift()   -> LinkedList.pollFirst();
unshift() -> LinkedList.addFirst();

Store select query's output in one array in postgres

I had exactly the same problem. Just one more working modification of the solution given by Denis (the type must be specified):

SELECT ARRAY(
SELECT column_name::text
FROM information_schema.columns
WHERE table_name='aean'
)

Detecting input change in jQuery?

As others already suggested, the solution in your case is to sniff multiple events.
Plugins doing this job often listen for the following events:

$input.on('change keydown keypress keyup mousedown click mouseup', handler);

If you think it may fit, you can add focus, blur and other events too.
I suggest not to exceed in the events to listen, as it loads in the browser memory further procedures to execute according to the user's behaviour.

Attention: note that changing the value of an input element with JavaScript (e.g. through the jQuery .val() method) won't fire any of the events above.
(Reference: https://api.jquery.com/change/).

Get program execution time in the shell

You can get much more detailed information than the bash built-in time (which Robert Gamble mentions) using time(1). Normally this is /usr/bin/time.

Editor's note: To ensure that you're invoking the external utility time rather than your shell's time keyword, invoke it as /usr/bin/time.
time is a POSIX-mandated utility, but the only option it is required to support is -p.
Specific platforms implement specific, nonstandard extensions: -v works with GNU's time utility, as demonstrated below (the question is tagged ); the BSD/macOS implementation uses -l to produce similar output - see man 1 time.

Example of verbose output:

$ /usr/bin/time -v sleep 1
       Command being timed: "sleep 1"
       User time (seconds): 0.00
       System time (seconds): 0.00
       Percent of CPU this job got: 1%
       Elapsed (wall clock) time (h:mm:ss or m:ss): 0:01.05
       Average shared text size (kbytes): 0
       Average unshared data size (kbytes): 0
       Average stack size (kbytes): 0
       Average total size (kbytes): 0
       Maximum resident set size (kbytes): 0
       Average resident set size (kbytes): 0
       Major (requiring I/O) page faults: 0
       Minor (reclaiming a frame) page faults: 210
       Voluntary context switches: 2
       Involuntary context switches: 1
       Swaps: 0
       File system inputs: 0
       File system outputs: 0
       Socket messages sent: 0
       Socket messages received: 0
       Signals delivered: 0
       Page size (bytes): 4096
       Exit status: 0

javascript check for not null

Check https://softwareengineering.stackexchange.com/a/253723

if(value) {
}

will evaluate to true if value is not:

null
undefined
NaN
empty string ("")
0
false

How to add element in List while iterating in java?

Just iterate the old-fashion way, because you need explicit index handling:

List myList = ...
...
int length = myList.size();
for(int i = 0; i < length; i++) {
   String s = myList.get(i);
   // add items here, if you want to
}

How to use fetch in typescript

If you take a look at @types/node-fetch you will see the body definition

export class Body {
    bodyUsed: boolean;
    body: NodeJS.ReadableStream;
    json(): Promise<any>;
    json<T>(): Promise<T>;
    text(): Promise<string>;
    buffer(): Promise<Buffer>;
}

That means that you could use generics in order to achieve what you want. I didn't test this code, but it would looks something like this:

import { Actor } from './models/actor';

fetch(`http://swapi.co/api/people/1/`)
      .then(res => res.json<Actor>())
      .then(res => {
          let b:Actor = res;
      });

How to set the max size of upload file

To avoid this exception you can take help of VM arguments just as I used in Spring 1.5.8.RELEASE:

-Dspring.http.multipart.maxFileSize=70Mb
-Dspring.http.multipart.maxRequestSize=70Mb

Twitter Bootstrap Datepicker within modal window

if You use bootstrap V3 try this.


    .bootstrap-datetimepicker-widget 
    {
        z-index: 1200   !important;
    }

Is there any way to call a function periodically in JavaScript?

The native way is indeed setInterval()/clearInterval(), but if you are already using the Prototype library you can take advantage of PeriodicalExecutor:

new PeriodicalUpdator(myEvent, seconds);

This prevents overlapping calls. From http://www.prototypejs.org/api/periodicalExecuter:

"it shields you against multiple parallel executions of the callback function, should it take longer than the given interval to execute (it maintains an internal “running” flag, which is shielded against exceptions in the callback function). This is especially useful if you use one to interact with the user at given intervals (e.g. use a prompt or confirm call): this will avoid multiple message boxes all waiting to be actioned."

Ping a site in Python?

You may find Noah Gift's presentation Creating Agile Commandline Tools With Python. In it he combines subprocess, Queue and threading to develop solution that is capable of pinging hosts concurrently and speeding up the process. Below is a basic version before he adds command line parsing and some other features. The code to this version and others can be found here

#!/usr/bin/env python2.5
from threading import Thread
import subprocess
from Queue import Queue

num_threads = 4
queue = Queue()
ips = ["10.0.1.1", "10.0.1.3", "10.0.1.11", "10.0.1.51"]
#wraps system ping command
def pinger(i, q):
    """Pings subnet"""
    while True:
        ip = q.get()
        print "Thread %s: Pinging %s" % (i, ip)
        ret = subprocess.call("ping -c 1 %s" % ip,
            shell=True,
            stdout=open('/dev/null', 'w'),
            stderr=subprocess.STDOUT)
        if ret == 0:
            print "%s: is alive" % ip
        else:
            print "%s: did not respond" % ip
        q.task_done()
#Spawn thread pool
for i in range(num_threads):

    worker = Thread(target=pinger, args=(i, queue))
    worker.setDaemon(True)
    worker.start()
#Place work in queue
for ip in ips:
    queue.put(ip)
#Wait until worker threads are done to exit    
queue.join()

He is also author of: Python for Unix and Linux System Administration

http://ecx.images-amazon.com/images/I/515qmR%2B4sjL._SL500_AA240_.jpg

What does "Changes not staged for commit" mean

Try following int git bash

1.git add -u :/

2.git commit -m "your commit message"

  1. git push -u origin master

Note:if you have not initialized your repo.

First of all

git init 

and follow above mentioned steps in order. This worked for me

How to change Angular CLI favicon

Deleting chromes favicon cache and restarting the browser on the mac worked for me.

rm ~/Library/Application\ Support/Google/Chrome/Default/Favicons

Unable to start debugging on the web server. Could not start ASP.NET debugging VS 2010, II7, Win 7 x64

Visual Studio, when starting up, will (for some reason) attempt to access the URL:

/debugattach.aspx

If you have a rewrite rule that redirects (or otherwise catches), say, .aspx files, somewhere else then you will get this error. The solution is to add this section to the beginning of your web.config's <system.webServer>/<rewrite>/<rules> section:

<rule name="Ignore Default.aspx" enabled="true" stopProcessing="true">
    <match url="^debugattach\.aspx" />
    <conditions logicalGrouping="MatchAll" trackAllCaptures="false" />
    <action type="None" />
</rule>

This will make sure to catch this one particular request, do nothing, and, most importantly, stop execution so none of your other rules will get run. This is a robust solution, so feel free to keep this in your config file for production.

jQuery textbox change event doesn't fire until textbox loses focus?

Binding to both events is the typical way to do it. You can also bind to the paste event.

You can bind to multiple events like this:

$("#textbox").on('change keyup paste', function() {
    console.log('I am pretty sure the text box changed');
});

If you wanted to be pedantic about it, you should also bind to mouseup to cater for dragging text around, and add a lastValue variable to ensure that the text actually did change:

var lastValue = '';
$("#textbox").on('change keyup paste mouseup', function() {
    if ($(this).val() != lastValue) {
        lastValue = $(this).val();
        console.log('The text box really changed this time');
    }
});

And if you want to be super duper pedantic then you should use an interval timer to cater for auto fill, plugins, etc:

var lastValue = '';
setInterval(function() {
    if ($("#textbox").val() != lastValue) {
        lastValue = $("#textbox").val();
        console.log('I am definitely sure the text box realy realy changed this time');
    }
}, 500);

How do I run Visual Studio as an administrator by default?

For Windows 8

  1. right click on the shortcut
  2. click on properties
  3. click on the "Shortcut" tab
  4. click on Advanced

You will find Run As administrator (Checkbox)

Programmatically Lighten or Darken a hex color (or rgb, and blend colors)

The following method will allow you to lighten or darken the exposure value of a Hexadecimal (Hex) color string:

private static string GetHexFromRGB(byte r, byte g, byte b, double exposure)
{
    exposure = Math.Max(Math.Min(exposure, 1.0), -1.0);
    if (exposure >= 0)
    {
        return "#"
            + ((byte)(r + ((byte.MaxValue - r) * exposure))).ToString("X2")
            + ((byte)(g + ((byte.MaxValue - g) * exposure))).ToString("X2")
            + ((byte)(b + ((byte.MaxValue - b) * exposure))).ToString("X2");
    }
    else
    {
        return "#"
            + ((byte)(r + (r * exposure))).ToString("X2")
            + ((byte)(g + (g * exposure))).ToString("X2")
            + ((byte)(b + (b * exposure))).ToString("X2");
    }

}

For the last parameter value in GetHexFromRGB(), Pass in a double value somewhere between -1 and 1 (-1 is black, 0 is unchanged, 1 is white):

// split color (#e04006) into three strings
var r = Convert.ToByte("e0", 16);
var g = Convert.ToByte("40", 16);
var b = Convert.ToByte("06", 16);

GetHexFromRGB(r, g, b, 0.25);  // Lighten by 25%;

Apache Spark: The number of cores vs. the number of executors

I think one of the major reasons is locality. Your input file size is 165G, the file's related blocks certainly distributed over multiple DataNodes, more executors can avoid network copy.

Try to set executor num equal blocks count, i think can be faster.

Increment value in mysql update query

You should use PDO to prevent SQL injection risk.

You can connect to DB like this :

try {
    $pdo_options[PDO::ATTR_ERRMODE] = PDO::ERRMODE_EXCEPTION;
    $bdd = new PDO('mysql:host=xxxx;dbname=xxxx', 'user', 'password', $pdo_options);
    $bdd->query('SET NAMES "utf8"');
} catch (PDOException $e) {
    exit('Error');
}

No need to query DB to get the number of points. You can increment directly in the update query (points = points + 1).

(note : Also, it’s not a good idea to increment the value with PHP because you need to select first the data and the value can changed if other users are updated it.)

$req = $bdd->prepare('UPDATE member_profile SET 
            points = points + 1
            WHERE user_id = :user_id');

$req->execute(array(
    'user_id' => $userid
));

Browse files and subfolders in Python

Slightly altered version of Sven Marnach's solution..


import os

folder_location = 'C:\SomeFolderName' file_list = create_file_list(folder_location)

def create_file_list(path): return_list = []

for filenames in os.walk(path): for file_list in filenames: for file_name in file_list: if file_name.endswith((".txt")): return_list.append(file_name) return return_list

SQL update trigger only when column is modified

One should check if QtyToRepair is updated at first.

ALTER TRIGGER [dbo].[tr_SCHEDULE_Modified]
   ON [dbo].[SCHEDULE]
   AFTER UPDATE
AS 
BEGIN
SET NOCOUNT ON;
    IF UPDATE (QtyToRepair) 
    BEGIN
        UPDATE SCHEDULE 
        SET modified = GETDATE()
           , ModifiedUser = SUSER_NAME()
           , ModifiedHost = HOST_NAME()
        FROM SCHEDULE S INNER JOIN Inserted I 
            ON S.OrderNo = I.OrderNo and S.PartNumber =    I.PartNumber
        WHERE S.QtyToRepair <> I.QtyToRepair
    END
END

How to convert a JSON string to a dictionary?

I found code which converts the json string to NSDictionary or NSArray. Just add the extension.

SWIFT 3.0

HOW TO USE

let jsonData = (convertedJsonString as! String).parseJSONString

EXTENSION

extension String
{
var parseJSONString: AnyObject?
{
    let data = self.data(using: String.Encoding.utf8, allowLossyConversion: false)
    if let jsonData = data
    {
        // Will return an object or nil if JSON decoding fails
        do
        {
            let message = try JSONSerialization.jsonObject(with: jsonData, options:.mutableContainers)
            if let jsonResult = message as? NSMutableArray {
                return jsonResult //Will return the json array output
            } else if let jsonResult = message as? NSMutableDictionary {
                return jsonResult //Will return the json dictionary output
            } else {
                return nil
            }
        }
        catch let error as NSError
        {
            print("An error occurred: \(error)")
            return nil
        }
    }
    else
    {
        // Lossless conversion of the string was not possible
        return nil
    }
}

}

How can I fix assembly version conflicts with JSON.NET after updating NuGet package references in a new ASP.NET MVC 5 project?

I found to delete this section from the project file fix the problem.

<ItemGroup>
<Reference Include="Newtonsoft.Json">
  <HintPath>..\packages\Newtonsoft.Json.6.0.1\lib\net45\Newtonsoft.Json.dll</HintPath>
</Reference>

SQL Views - no variables?

How often do you need to refresh the view? I have a similar case where the new data comes once a month; then I have to load it, and during the loading processes I have to create new tables. At that moment I alter my view to consider the changes. I used as base the information in this other question:

Create View Dynamically & synonyms

In there, it is proposed to do it 2 ways:

  1. using synonyms.
  2. Using dynamic SQL to create view (this is what helped me achieve my result).

Grab a segment of an array in Java without creating a new array on heap

The Lists allow you to use and work with subList of something transparently. Primitive arrays would require you to keep track of some kind of offset - limit. ByteBuffers have similar options as I heard.

Edit: If you are in charge of the useful method, you could just define it with bounds (as done in many array related methods in java itself:

doUseful(byte[] arr, int start, int len) {
    // implementation here
}
doUseful(byte[] arr) {
    doUseful(arr, 0, arr.length);
}

It's not clear, however, if you work on the array elements themselves, e.g. you compute something and write back the result?

Breaking out of a nested loop

Throw a custom exception which goes out outter loop.

It works for for,foreach or while or any kind of loop and any language that uses try catch exception block

try 
{
   foreach (object o in list)
   {
      foreach (object another in otherList)
      {
         // ... some stuff here
         if (condition)
         {
            throw new CustomExcpetion();
         }
      }
   }
}
catch (CustomException)
{
   // log 
}

Iterate over object in Angular

try to use this pipe

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({ name: 'values',  pure: false })
export class ValuesPipe implements PipeTransform {
  transform(value: any, args: any[] = null): any {
    return Object.keys(value).map(key => value[key]);
  }
}

<div *ngFor="#value of object | values"> </div>

Could not load file or assembly Microsoft.SqlServer.management.sdk.sfc version 11.0.0.0

Problem: (Sql server 2014) This issue happens when assembly Microsoft.SqlServer.management.sdk.sfc version 12.0.0.0 not found by visual studio.

Solution: just go to http://www.microsoft.com/en-us/download/details.aspx?id=42295 and download:

  • ENU\x64\SharedManagementObjects.msi for X64 OS or
  • ENU\x86\SharedManagementObjects.msi for X86 OS,

then install it, and restart visual studio.

PS: You may need install DB2OLEDBV5_x64.msi or DB2OLEDBV5_x86.msi too.


Problem: (Sql server 2012) This issue happens when assembly Microsoft.SqlServer.management.sdk.sfc version 11.0.0.0 not found by visual studio.

Solution: just go to http://www.microsoft.com/en-us/download/details.aspx?id=35580 and download:

  • ENU\x64\SharedManagementObjects.msi for X64 OS or
  • ENU\x86\SharedManagementObjects.msi for X86 OS,

then install it, and restart visual studio.


Problem: (Sql server 2008) This issue happens when assembly Microsoft.SqlServer.management.sdk.sfc version 10.0.0.0 not found by visual studio.

Solution: just go to http://www.microsoft.com/en-us/download/details.aspx?id=26728 and download:

  • 1033\x64\SharedManagementObjects.msi for X64 OS or
  • 1033\x86\SharedManagementObjects.msi for X86 OS,

(In most cases downloading this is better http://go.microsoft.com/fwlink/?LinkId=123708&clcid=0x409)

then install it, and restart visual studio.


Problem: I recently got similar problem after installing SharedManagementObjects. assembly Microsoft.SqlServer.ConnectionInfo, Version=12.0.0.0 not found by visual studio. The problem was Visual C++ Redistributable Packages for Visual Studio was not installed yet.

Solution: for Visual Studio 2013 just go to http://www.microsoft.com/en-us/download/details.aspx?id=40784 and download:

  • vcredist_x64.exe for X64 OS or
  • vcredist_x86.exe for X86 OS,

then install it, and restart visual studio.

PS: You can find Visual C++ Redistributable Packages for Visual Studio 20XX for other versions of Visual Studio easily by googling it.

How to use a calculated column to calculate another column in the same view

In SQL Server

You can do this using With CTE

WITH common_table_expression (Transact-SQL)

CREATE TABLE tab(ColumnA DECIMAL(10,2), ColumnB DECIMAL(10,2), ColumnC DECIMAL(10,2))

INSERT INTO tab(ColumnA, ColumnB, ColumnC) VALUES (2, 10, 2),(3, 15, 6),(7, 14, 3)

WITH tab_CTE (ColumnA, ColumnB, ColumnC,calccolumn1)  
AS  
(  
Select
    ColumnA,
    ColumnB,
    ColumnC,
    ColumnA + ColumnB As calccolumn1
  from tab
)  

SELECT
  ColumnA,
  ColumnB,
  calccolumn1,
  calccolumn1 / ColumnC AS calccolumn2
FROM  tab_CTE

DBFiddle Demo

Receiving login prompt using integrated windows authentication

I had the same problem cause the user (Identity) that I used in the application pool was not belowing to IIS_IUSRS group. Added the user to the group and everything work

Get selected value of a dropdown's item using jQuery

Try this, it gets the value:

$('select#myField').find('option:selected').val();

Determine the number of NA values in a column

A tidyverse way to count the number of nulls in every column of a dataframe:

library(tidyverse)
library(purrr)

df %>%
    map_df(function(x) sum(is.na(x))) %>%
    gather(feature, num_nulls) %>%
    print(n = 100)

Could not find tools.jar. Please check that C:\Program Files\Java\jre1.8.0_151 contains a valid JDK installation

What worked for me was updating Android Studio and updating JAVA_HOME and ANDROID_HOME environment variables. I believe it was caused due to the fact that I updated Java Version (through updater) but did not update jdk.

Is it possible to see more than 65536 rows in Excel 2007?

I have found that the 65536 limit still applies to pivot tables, even in Excel 2007.

C++ String Concatenation operator<<

nametext is an std::string but these do not have the stream insertion operator (<<) like output streams do.

To concatenate strings you can use the append member function (or its equivalent, +=, which works in the exact same way) or the + operator, which creates a new string as a result of concatenating the previous two.

Select distinct rows from datatable in Linq

Dim distinctValues As List(Of Double) = (From r In _
DirectCast(DataTable.AsEnumerable(),IEnumerable(Of DataRow)) Where (Not r.IsNull("ColName")) _
Select r.Field(Of Double)("ColName")).Distinct().ToList()

Removing duplicates in the lists

You can use set to remove duplicates:

mylist = list(set(mylist))

But note the results will be unordered. If that's an issue:

mylist.sort()

PHP string "contains"

You can use stristr() or strpos(). Both return false if nothing is found.

C++ pointer to objects

if you want to access a method :

1) while using an object of a class:

Myclass myclass;
myclass.DoSomething();

2) while using a pointer to an object of a class:

Myclass *myclass=&abc;
myclass->DoSomething();

How to run crontab job every week on Sunday

* * * * 0 

you can use above cron job to run on every week on sunday, but in addition on what time you want to run this job for that you can follow below concept :

* * * * *  Command_to_execute
- ? ? ? -
| | | | |
| | | | +?? Day of week (0?6) (Sunday=0) or Sun, Mon, Tue,...
| | | +???- Month (1?12) or Jan, Feb,...
| | +????-? Day of month (1?31)
| +??????? Hour (0?23)
+????????- Minute (0?59)

How to strip a specific word from a string?

You can also use a regexp with re.sub:

article_title_str = re.sub(r'(\s?-?\|?\s?Times of India|\s?-?\|?\s?the Times of India|\s?-?\|?\s+?Gadgets No'',
                           article_title_str, flags=re.IGNORECASE)

SQL split values to multiple rows

Here is my attempt: The first select presents the csv field to the split. Using recursive CTE, we can create a list of numbers that are limited to the number of terms in the csv field. The number of terms is just the difference in the length of the csv field and itself with all the delimiters removed. Then joining with this numbers, substring_index extracts that term.

with recursive
    T as ( select 'a,b,c,d,e,f' as items),
    N as ( select 1 as n union select n + 1 from N, T
        where n <= length(items) - length(replace(items, ',', '')))
    select distinct substring_index(substring_index(items, ',', n), ',', -1)
group_name from N, T

How can I connect to MySQL in Python 3 on Windows?

I also tried using pymysql (on my Win7 x64 machine, Python 3.3), without too much luck. I downloaded the .tar.gz, extract, ran "setup.py install", and everything seemed fine. Until I tried connecting to a database, and got "KeyError [56]". An error which I was unable to find documented anywhere.

So I gave up on pymysql, and I settled on the Oracle MySQL connector.

It comes as a setup package, and works out of the box. And it also seems decently documented.

Catching KeyboardInterrupt in Python during program shutdown

Checkout this thread, it has some useful information about exiting and tracebacks.

If you are more interested in just killing the program, try something like this (this will take the legs out from under the cleanup code as well):

if __name__ == '__main__':
    try:
        main()
    except KeyboardInterrupt:
        print('Interrupted')
        try:
            sys.exit(0)
        except SystemExit:
            os._exit(0)

JQuery - Storing ajax response into global variable

I'd suggest that fetching large XML files from the server should be avoided: the variable "xml" should used like a cache, and not as the data store itself.

In most scenarios, it is possible to examine the cache and see if you need to make a request to the server to get the data that you want. This will make your app lighter and faster.

cheers, jrh.

1067 error on attempt to start MySQL

I also get log with Table 'mysql.plugin' doesn't exist if install MYSQL Server 5.1 by 'msiexec.exe' DataDir I put as C:\MYSQL\MySQL_Server_5_1\data\

but to my surprise was create data in a C:\MYSQL\MySQL_Server_5_1\data\data

There are was add word data . So I change my.ini file from

datadir="C:/MySQL/MySQL_Server_5_1/Data/" .

to the

datadir="C:/MySQL/MySQL_Server_5_1/Data/data"

and then I can use net start MYSQL51 and then mysqld.exe run and appear in a Task Manager

How to open this .DB file?

I don't think there is a way to tell which program to use from just the .db extension. It could even be an encrypted database which can't be opened. You can MS Access, or a sqlite manager.

Edit: Try to rename the file to .txt and open it with a text editor. The first couple of words in the file could tell you the DB Type.

If it is a SQLite database, it will start with "SQLite format 3"

How to get a single value from FormGroup

You can use getRawValue()

this.formGroup.getRawValue().attribute

The server is not responding (or the local MySQL server's socket is not correctly configured) in wamp server

I use XAMPP and had the same error. I used Paul Gobée solution above and it worked for me. I navigated to C:\xampp\mysql\bin\mysqld-debug.exe and upon starting the .exe my Windows Firewall popped up asking for permission. Once I allowed it, it worked fine. I would have commented under his post but I do not have that much rep yet... sry! Just wanted to let everyone know this worked for me as well.

Curl error 60, SSL certificate issue: self signed certificate in certificate chain

Important: This issue drove me crazy for a couple days and I couldn't figure out what was going on with my curl & openssl installations. I finally figured out that it was my intermediate certificate (in my case, GoDaddy) which was out of date. I went back to my godaddy SSL admin panel, downloaded the new intermediate certificate, and the issue disappeared.

I'm sure this is the issue for some of you.

Apparently, GoDaddy had changed their intermediate certificate at some point, due to scurity issues, as they now display this warning:

"Please be sure to use the new SHA-2 intermediate certificates included in your downloaded bundle."

Hope this helps some of you, because I was going nuts and this cleaned up the issue on ALL my servers.

Adding form action in html in laravel

Use action="{{ action('WelcomeController@log_in') }}"

however TokenMismatchException means that you are missing a CSRF token in your form.

You can add this by using <input name="_token" type="hidden" value="{{ csrf_token() }}">

Child inside parent with min-height: 100% not inheriting height

This usually works for me:


_x000D_
_x000D_
.parent {_x000D_
  min-height: 100px;_x000D_
  background-color: green;_x000D_
  display: flex;_x000D_
}_x000D_
.child {_x000D_
  height: inherit;_x000D_
  width: 100%;_x000D_
  background-color: red;_x000D_
}
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
  <body>_x000D_
    <div class="parent">_x000D_
      <div class="child">_x000D_
      </div>_x000D_
    </div>_x000D_
  </body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

Find duplicate entries in a column

Try this query.. It uses the Analytic function SUM:

SELECT * FROM
(  
 SELECT SUM(1) OVER(PARTITION BY ctn_no) cnt, A.*
 FROM table1 a 
 WHERE s_ind ='Y'   
)
WHERE cnt > 2

Am not sure why you are identifying a record as a duplicate if the ctn_no repeats more than 2 times. FOr me it repeats more than once it is a duplicate. In this case change the las part of the query to WHERE cnt > 1

How to use img src in vue.js?

Try this:

<img v-bind:src="'/media/avatars/' + joke.avatar" /> 

Don't forget single quote around your path string. also in your data check you have correctly defined image variable.

joke: {
  avatar: 'image.jpg'
}

A working demo here: http://jsbin.com/pivecunode/1/edit?html,js,output

How do I format date in jQuery datetimepicker?

For example, I get date/time in format Spanish.

$('#timePicker').datetimepicker({
    defaultDate: new Date(),
    format:'DD/MM/YYYY HH:mm'
});

Check whether IIS is installed or not?

Refer this a step by step approach:

http://www.codeproject.com/Tips/365704/Install-IIS-on-Windows

For many users you have to enable the windows feature on then check IIS and then go with RUN followed by searching for inetmgr.

Clicking the back button twice to exit an activity

You can also use the visibility of a Toast, so you don't need that Handler/postDelayed ultra solution.

Toast doubleBackButtonToast;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    doubleBackButtonToast = Toast.makeText(this, "Double tap back to exit.", Toast.LENGTH_SHORT);
}

@Override
public void onBackPressed() {
    if (doubleBackButtonToast.getView().isShown()) {
        super.onBackPressed();
    }

    doubleBackButtonToast.show();
}

Convert a numpy.ndarray to string(or bytes) and convert it back to numpy.ndarray

If you use tostring you lose information on both shape and data type:

>>> import numpy as np
>>> a = np.arange(12).reshape(3, 4)
>>> a
array([[ 0,  1,  2,  3],
       [ 4,  5,  6,  7],
       [ 8,  9, 10, 11]])
>>> s = a.tostring()
>>> aa = np.fromstring(a)
>>> aa
array([  0.00000000e+000,   4.94065646e-324,   9.88131292e-324,
         1.48219694e-323,   1.97626258e-323,   2.47032823e-323,
         2.96439388e-323,   3.45845952e-323,   3.95252517e-323,
         4.44659081e-323,   4.94065646e-323,   5.43472210e-323])
>>> aa = np.fromstring(a, dtype=int)
>>> aa
array([ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11])
>>> aa = np.fromstring(a, dtype=int).reshape(3, 4)
>>> aa
array([[ 0,  1,  2,  3],
       [ 4,  5,  6,  7],
       [ 8,  9, 10, 11]])

This means you have to send the metadata along with the data to the recipient. To exchange auto-consistent objects, try cPickle:

>>> import cPickle
>>> s = cPickle.dumps(a)
>>> cPickle.loads(s)
array([[ 0,  1,  2,  3],
       [ 4,  5,  6,  7],
       [ 8,  9, 10, 11]])

Convert utf8-characters to iso-88591 and back in PHP

Have a look at iconv() or mb_convert_encoding(). Just by the way: why don't utf8_encode() and utf8_decode() work for you?

utf8_decode — Converts a string with ISO-8859-1 characters encoded with UTF-8 to single-byte ISO-8859-1

utf8_encode — Encodes an ISO-8859-1 string to UTF-8

So essentially

$utf8 = 'ÄÖÜ'; // file must be UTF-8 encoded
$iso88591_1 = utf8_decode($utf8);
$iso88591_2 = iconv('UTF-8', 'ISO-8859-1', $utf8);
$iso88591_2 = mb_convert_encoding($utf8, 'ISO-8859-1', 'UTF-8');

$iso88591 = 'ÄÖÜ'; // file must be ISO-8859-1 encoded
$utf8_1 = utf8_encode($iso88591);
$utf8_2 = iconv('ISO-8859-1', 'UTF-8', $iso88591);
$utf8_2 = mb_convert_encoding($iso88591, 'UTF-8', 'ISO-8859-1');

all should do the same - with utf8_en/decode() requiring no special extension, mb_convert_encoding() requiring ext/mbstring and iconv() requiring ext/iconv.

How to find available directory objects on Oracle 11g system?

The ALL_DIRECTORIES data dictionary view will have information about all the directories that you have access to. That includes the operating system path

SELECT owner, directory_name, directory_path
  FROM all_directories

Show history of a file?

You can use git log to display the diffs while searching:

git log -p -- path/to/file

Populating VBA dynamic arrays

in your for loop use a Redim on the array like here:

For i = 0 to 3
  ReDim Preserve test(i)
  test(i) = 3 + i
Next i

Laravel 5.2 Missing required parameters for [Route: user.profile] [URI: user/{nickname}/profile]

My Solution in laravel 5.2

{{ Form::open(['route' => ['votes.submit', $video->id],  'method' => 'POST']) }}
    <button type="submit" class="btn btn-primary">
        <span class="glyphicon glyphicon-thumbs-up"></span> Votar
    </button>
{{ Form::close() }}

My Routes File (under middleware)

Route::post('votar/{id}', [
    'as' => 'votes.submit',
    'uses' => 'VotesController@submit'
]);

Route::delete('votar/{id}', [
    'as' => 'votes.destroy',
    'uses' => 'VotesController@destroy'
]);

How to encode a string in JavaScript for displaying in HTML?

function htmlEntities(str) {
    return String(str).replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;');
}

So then with var unsafestring = "<oohlook&atme>"; you would use htmlEntities(unsafestring);

How do I push amended commit to the remote Git repository?

You are getting this error because the Git remote already has these commit files. You have to force push the branch for this to work:

git push -f origin branch_name

Also make sure you pull the code from remote as someone else on your team might have pushed to the same branch.

git pull origin branch_name

This is one of the cases where we have to force push the commit to remote.

Converting dd/mm/yyyy formatted string to Datetime

use DateTime.ParseExact

string strDate = "24/01/2013";
DateTime date = DateTime.ParseExact(strDate, "dd/MM/YYYY", null)

null will use the current culture, which is somewhat dangerous. Try to supply a specific culture

DateTime date = DateTime.ParseExact(strDate, "dd/MM/YYYY", CultureInfo.InvariantCulture)

simple Jquery hover enlarge

Well I'm not exactly sure why your code is not working because I usually follow a different approach when trying to accomplish something similar.

But your code is erroring out.. There seems to be an issue with the way you are using scale I got the jQuery to actually execute by changing your code to the following.

$(document).ready(function(){
    $('img').hover(function() {
        $(this).css("cursor", "pointer");
        $(this).toggle({
          effect: "scale",
          percent: "90%"
        },200);
    }, function() {
         $(this).toggle({
           effect: "scale",
           percent: "80%"
         },200);

    });
});  

But I have always done it by using CSS to setup my scaling and transition..

Here is an example, hopefully it helps.

$(document).ready(function(){
    $('#content').hover(function() {
        $("#content").addClass('transition');

    }, function() {
        $("#content").removeClass('transition');
    });
});

http://jsfiddle.net/y4yAP/

Deploying Java webapp to Tomcat 8 running in Docker container

There's a oneliner for this one.

You can simply run,

docker run -v /1.0-SNAPSHOT/my-app-1.0-SNAPSHOT.war:/usr/local/tomcat/webapps/myapp.war -it -p 8080:8080 tomcat

This will copy the war file to webapps directory and get your app running in no time.

C++ template constructor

You could do this:

class C 
{
public:
    template <typename T> C(T*);
};
template <typename T> T* UseType() 
{
    static_cast<T*>(nullptr);
}

Then to create an object of type C using int as the template parameter to the constructor:

C obj(UseType<int>());

Since you can't pass template parameters to a constructor, this solution essentially converts the template parameter to a regular parameter. Using the UseType<T>() function when calling the constructor makes it clear to someone looking at the code that the purpose of that parameter is to tell the constructor what type to use.

One use case for this would be if the constructor creates a derived class object and assigns it to a member variable that is a base class pointer. (The constructor needs to know which derived class to use, but the class itself doesn't need to be templated since the same base class pointer type is always used.)

ImportError: No module named PyQt4.QtCore

You don't have g++ installed, simple way to have all the needed build tools is to install the package build-essential:

sudo apt-get install build-essential

, or just the g++ package:

sudo apt-get install g++

The authorization mechanism you have provided is not supported. Please use AWS4-HMAC-SHA256

AWS_S3_REGION_NAME = "ap-south-1"

AWS_S3_SIGNATURE_VERSION = "s3v4"

this also saved my time after surfing for 24Hours..

What are native methods in Java and where should they be used?

Native methods allow you to use code from other languages such as C or C++ in your java code. You use them when java doesn't provide the functionality that you need. For example, if I were writing a program to calculate some equation and create a line graph of it, I would use java, because it is the language I am best in. However, I am also proficient in C. Say in part of my program I need to calculate a really complex equation. I would use a native method for this, because I know some C++ and I know that C++ is much faster than java, so if I wrote my method in C++ it would be quicker. Also, say I want to interact with another program or device. This would also use a native method, because C++ has something called pointers, which would let me do that.

Two Page Login with Spring Security 3.2.x

There should be three pages here:

  1. Initial login page with a form that asks for your username, but not your password.
  2. You didn't mention this one, but I'd check whether the client computer is recognized, and if not, then challenge the user with either a CAPTCHA or else a security question. Otherwise the phishing site can simply use the tendered username to query the real site for the security image, which defeats the purpose of having a security image. (A security question is probably better here since with a CAPTCHA the attacker could have humans sitting there answering the CAPTCHAs to get at the security images. Depends how paranoid you want to be.)
  3. A page after that that displays the security image and asks for the password.

I don't see this short, linear flow being sufficiently complex to warrant using Spring Web Flow.

I would just use straight Spring Web MVC for steps 1 and 2. I wouldn't use Spring Security for the initial login form, because Spring Security's login form expects a password and a login processing URL. Similarly, Spring Security doesn't provide special support for CAPTCHAs or security questions, so you can just use Spring Web MVC once again.

You can handle step 3 using Spring Security, since now you have a username and a password. The form login page should display the security image, and it should include the user-provided username as a hidden form field to make Spring Security happy when the user submits the login form. The only way to get to step 3 is to have a successful POST submission on step 1 (and 2 if applicable).

Bootstrap: wider input field

I made a wider input field by using either span4 or span6 as class.

<input type="text" class="span6 input-large search-query">

This way you don't need the additional custom css, mentioned earlier.

Angular.js vs Knockout.js vs Backbone.js

It depends on the nature of your application. And, since you did not describe it in great detail, it is an impossible question to answer. I find Backbone to be the easiest, but I work in Angular all day. Performance is more up to the coder than the framework, in my opinion.

Are you doing heavy DOM manipulation? I would use jQuery and Backbone.

Very data driven app? Angular with its nice data binding.

Game programming? None - direct to canvas; maybe a game engine.

NodeJS - Error installing with NPM

Make sure you have all the required software to run node-gyp:

You can configure version of Visual Studio used by node-gyp via an environment variable so you can avoid having to set the --msvs_version=2012 property every time you do an npm install.

Examples:

  • set GYP_MSVS_VERSION=2012 for Visual Studio 2012
  • set GYP_MSVS_VERSION=2013e (the 'e' stands for FREE 'express edition')

For the full list see - https://github.com/joyent/node/blob/v0.10.29/tools/gyp/pylib/gyp/MSVSVersion.py#L209-294

This is still painful for Windows users of NodeJS as it assumes you have a copy of Visual Studio installed and many end users will never have this. So I'm lobbying Joyent to the encourage them to include web sockets as part of CORE node and also to possible ship a GNU gcc compiler as part of NodeJS install so we can permanently fix this problem.

Feel free to add your vote at:

How can I execute Python scripts using Anaconda's version of Python?

I know this is old, but none of the answers here is a real solution if you want to be able to double-click Python files and have the correct interpreter used without modifying your PYTHONPATH or PATH every time you want to use a different interpreter. Sure, from the command line, activate my-environment works, but OP specifically asked about double-clicking.

In this case, the correct thing to do is use the Python launcher for Windows. Then, all you have to do is add #! path\to\interpreter\python.exe to the top of your script. Unfortunately, although the launcher comes standard with Python 3.3+, it is not included with Anaconda (see Python & Windows: Where is the python launcher?), and the simplest thing to do is to install it separately from here.

How can I use onItemSelected in Android?

Joseph: spinner.setOnItemSelectedListener(this) should be below Spinner firstSpinner = (Spinner) findViewById(R.id.spinner1); on onCreate

Python Function to test ping

Adding on to the other answers, you can check the OS and decide whether to use "-c" or "-n":

import os, platform
host = "8.8.8.8"
os.system("ping " + ("-n 1 " if  platform.system().lower()=="windows" else "-c 1 ") + host)

This will work on Windows, OS X, and Linux

You can also use sys:

import os, sys
host = "8.8.8.8"
os.system("ping " + ("-n 1 " if  sys.platform().lower()=="win32" else "-c 1 ") + host)

Forbidden: You don't have permission to access / on this server, WAMP Error

This could be one solution.

public class RegisterActivity extends AppCompatActivity {

    private static final String TAG = "RegisterActivity";
    private static final String URL_FOR_REGISTRATION = "http://192.168.10.4/android_login_example/register.php";
    ProgressDialog progressDialog;

    private EditText signupInputName, signupInputEmail, signupInputPassword, signupInputAge;
    private Button btnSignUp;
    private Button btnLinkLogin;
    private RadioGroup genderRadioGroup;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_register);
        // Progress dialog
        progressDialog = new ProgressDialog(this);
        progressDialog.setCancelable(false);

        signupInputName = (EditText) findViewById(R.id.signup_input_name);
        signupInputEmail = (EditText) findViewById(R.id.signup_input_email);
        signupInputPassword = (EditText) findViewById(R.id.signup_input_password);
        signupInputAge = (EditText) findViewById(R.id.signup_input_age);

        btnSignUp = (Button) findViewById(R.id.btn_signup);
        btnLinkLogin = (Button) findViewById(R.id.btn_link_login);

        genderRadioGroup = (RadioGroup) findViewById(R.id.gender_radio_group);
        btnSignUp.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                submitForm();
            }
        });
        btnLinkLogin.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                Intent i = new Intent(getApplicationContext(),MainActivity.class);
                startActivity(i);
            }
        });
    }

    private void submitForm() {

        int selectedId = genderRadioGroup.getCheckedRadioButtonId();
        String gender;
        if(selectedId == R.id.female_radio_btn)
            gender = "Female";
        else
            gender = "Male";

        registerUser(signupInputName.getText().toString(),
                signupInputEmail.getText().toString(),
                signupInputPassword.getText().toString(),
                gender,
                signupInputAge.getText().toString());
    }

    private void registerUser(final String name,  final String email, final String password,
                              final String gender, final String dob) {
        // Tag used to cancel the request
        String cancel_req_tag = "register";

        progressDialog.setMessage("Adding you ...");
        showDialog();

        StringRequest strReq = new StringRequest(Request.Method.POST,
                URL_FOR_REGISTRATION, new Response.Listener<String>() {

            @Override
            public void onResponse(String response) {
                Log.d(TAG, "Register Response: " + response.toString());
                hideDialog();

                try {
                    JSONObject jObj = new JSONObject(response);
                    boolean error = jObj.getBoolean("error");

                    if (!error) {
                        String user = jObj.getJSONObject("user").getString("name");
                        Toast.makeText(getApplicationContext(), "Hi " + user +", You are successfully Added!", Toast.LENGTH_SHORT).show();

                        // Launch login activity
                        Intent intent = new Intent(
                                RegisterActivity.this,
                                MainActivity.class);
                        startActivity(intent);
                        finish();
                    } else {



                        String errorMsg = jObj.getString("error_msg");
                        Toast.makeText(getApplicationContext(),
                                errorMsg, Toast.LENGTH_LONG).show();
                    }
                } catch (JSONException e) {
                    e.printStackTrace();
                }

            }
        }, new Response.ErrorListener() {

            @Override
            public void onErrorResponse(VolleyError error) {
                Log.e(TAG, "Registration Error: " + error.getMessage());
                Toast.makeText(getApplicationContext(),
                        error.getMessage(), Toast.LENGTH_LONG).show();
                hideDialog();
            }
        }) {
            @Override
            protected Map<String, String> getParams() {
                // Posting params to register url
                Map<String, String> params = new HashMap<String, String>();
                params.put("name", name);
                params.put("email", email);
                params.put("password", password);
                params.put("gender", gender);
                params.put("age", dob);
                return params;
            }
        };
        // Adding request to request queue
        AppSingleton.getInstance(getApplicationContext()).addToRequestQueue(strReq, cancel_req_tag);
    }

    private void showDialog() {
        if (!progressDialog.isShowing())
            progressDialog.show();
    }

    private void hideDialog() {
        if (progressDialog.isShowing())
            progressDialog.dismiss();
    }
    }

matplotlib does not show my drawings although I call pyplot.show()

For me the problem happens if I simply create an empty matplotlibrc file under ~/.matplotlib on macOS. Adding "backend: macosx" in it fixes the problem.

I think it is a bug: if backend is not specified in my matplotlibrc it should take the default value.

How to change an application icon programmatically in Android?

Try this, it works fine for me:

1 . Modify your MainActivity section in AndroidManifest.xml, delete from it, line with MAIN category in intent-filter section

<activity android:name="ru.quickmessage.pa.MainActivity"
    android:configChanges="keyboardHidden|orientation"
    android:screenOrientation="portrait"
    android:label="@string/app_name"
    android:theme="@style/CustomTheme"
    android:launchMode="singleTask">
    <intent-filter>
        ==> <action android:name="android.intent.action.MAIN" /> <== Delete this line
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>

2 . Create <activity-alias>, for each of your icons. Like this

<activity-alias android:label="@string/app_name" 
    android:icon="@drawable/icon" 
    android:name=".MainActivity-Red"
    android:enabled="false"
    android:targetActivity=".MainActivity">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>   
</activity-alias>

3 . Set programmatically: set ENABLE attribute for the appropriate activity-alias

 getPackageManager().setComponentEnabledSetting(
        new ComponentName("ru.quickmessage.pa", "ru.quickmessage.pa.MainActivity-Red"), 
            PackageManager.COMPONENT_ENABLED_STATE_ENABLED, PackageManager.DONT_KILL_APP);

Note, At least one must be enabled at all times.

Add context path to Spring Boot application

please note that the "server.context-path" or "server.servlet.context-path" [starting from springboot 2.0.x] properties will only work if you are deploying to an embedded container e.g., embedded tomcat. These properties will have no effect if you are deploying your application as a war to an external tomcat for example.

see this answer here: https://stackoverflow.com/a/43856300/4449859

How to redirect to a 404 in Rails?

The newly Selected answer submitted by Steven Soroka is close, but not complete. The test itself hides the fact that this is not returning a true 404 - it's returning a status of 200 - "success". The original answer was closer, but attempted to render the layout as if no failure had occurred. This fixes everything:

render :text => 'Not Found', :status => '404'

Here's a typical test set of mine for something I expect to return 404, using RSpec and Shoulda matchers:

describe "user view" do
  before do
    get :show, :id => 'nonsense'
  end

  it { should_not assign_to :user }

  it { should respond_with :not_found }
  it { should respond_with_content_type :html }

  it { should_not render_template :show }
  it { should_not render_with_layout }

  it { should_not set_the_flash }
end

This healthy paranoia allowed me to spot the content-type mismatch when everything else looked peachy :) I check for all these elements: assigned variables, response code, response content type, template rendered, layout rendered, flash messages.

I'll skip the content type check on applications that are strictly html...sometimes. After all, "a skeptic checks ALL the drawers" :)

http://dilbert.com/strips/comic/1998-01-20/

FYI: I don't recommend testing for things that are happening in the controller, ie "should_raise". What you care about is the output. My tests above allowed me to try various solutions, and the tests remain the same whether the solution is raising an exception, special rendering, etc.

JQuery - Get select value

val() returns the value of the <select> element, i.e. the value attribute of the selected <option> element.

Since you actually want the inner text of the selected <option> element, you should match that element and use text() instead:

var nationality = $("#dancerCountry option:selected").text();

How to install MinGW-w64 and MSYS2?

Unfortunately, the MinGW-w64 installer you used sometimes has this issue. I myself am not sure about why this happens (I think it has something to do with Sourceforge URL redirection or whatever that the installer currently can't handle properly enough).

Anyways, if you're already planning on using MSYS2, there's no need for that installer.

  1. Download MSYS2 from this page (choose 32 or 64-bit according to what version of Windows you are going to use it on, not what kind of executables you want to build, both versions can build both 32 and 64-bit binaries).

  2. After the install completes, click on the newly created "MSYS2 Shell" option under either MSYS2 64-bit or MSYS2 32-bit in the Start menu. Update MSYS2 according to the wiki (although I just do a pacman -Syu, ignore all errors and close the window and open a new one, this is not recommended and you should do what the wiki page says).

  3. Install a toolchain

    a) for 32-bit:

    pacman -S mingw-w64-i686-gcc
    

    b) for 64-bit:

    pacman -S mingw-w64-x86_64-gcc
    
  4. install any libraries/tools you may need. You can search the repositories by doing

    pacman -Ss name_of_something_i_want_to_install
    

    e.g.

    pacman -Ss gsl
    

    and install using

    pacman -S package_name_of_something_i_want_to_install
    

    e.g.

    pacman -S mingw-w64-x86_64-gsl
    

    and from then on the GSL library is automatically found by your MinGW-w64 64-bit compiler!

  5. Open a MinGW-w64 shell:

    a) To build 32-bit things, open the "MinGW-w64 32-bit Shell"

    b) To build 64-bit things, open the "MinGW-w64 64-bit Shell"

  6. Verify that the compiler is working by doing

    gcc -v
    

If you want to use the toolchains (with installed libraries) outside of the MSYS2 environment, all you need to do is add <MSYS2 root>/mingw32/bin or <MSYS2 root>/mingw64/bin to your PATH.

Postgres: check if array field contains value?

Instead of IN we can use ANY with arrays casted to enum array, for example:

create type example_enum as enum (
  'ENUM1', 'ENUM2'
);

create table example_table (
  id integer,
  enum_field example_enum
);

select 
  * 
from 
  example_table t
where
  t.enum_field = any(array['ENUM1', 'ENUM2']::example_enum[]);

Or we can still use 'IN' clause, but first, we should 'unnest' it:

select 
  * 
from 
  example_table t
where
  t.enum_field in (select unnest(array['ENUM1', 'ENUM2']::example_enum[]));

Example: https://www.db-fiddle.com/f/LaUNi42HVuL2WufxQyEiC/0

How to create a .NET DateTime from ISO 8601 format

using System.Globalization;

DateTime d;
DateTime.TryParseExact(
    "2010-08-20T15:00:00",
    "s",
    CultureInfo.InvariantCulture,
    DateTimeStyles.AssumeUniversal, out d);

How to remove tab indent from several lines in IDLE?

By default, IDLE has it on Shift-Left Bracket. However, if you want, you can customise it to be Shift-Tab by clicking Options --> Configure IDLE --> Keys --> Use a Custom Key Set --> dedent-region --> Get New Keys for Selection

Then you can choose whatever combination you want. (Don't forget to click apply otherwise all the settings would not get affected.)

android splash screen sizes for ldpi,mdpi, hdpi, xhdpi displays ? - eg : 1024X768 pixels for ldpi

For Android Mobile Devices

LDPI- icon-36x36, splash-426x320 (now with correct values)


MDPI- icon-48x48, splash-470x320


HDPI- icon 72x72, splash- 640x480


XHDPI- icon-96x96, splash- 960x720


XXHDPI- icon- 144x144

All in pixels.

For Android Tablet Devices

LDPI:
    Portrait: 200x320px
    Landscape: 320x200px
MDPI:
    Portrait: 320x480px
    Landscape: 480x320px
HDPI:
    Portrait: 480x800px
    Landscape: 800x480px
XHDPI:
    Portrait: 720px1280px
    Landscape: 1280x720px

How to edit the size of the submit button on a form?

Change height using:

input[type=submit] {
  border: none; /*rewriting standard style, it is necessary to be able to change the size*/
  height: 100px;
  width: 200px
}

javascript regex for special characters

What's the difference?

/[a-zA-Z0-9]/ is a character class which matches one character that is inside the class. It consists of three ranges.

/a-zA-Z0-9/ does mean the literal sequence of those 9 characters.

Which chars from .!@#$%^&*()_+-= are needed to be escaped?

Inside a character class, only the minus (if not at the end) and the circumflex (if at the beginning). Outside of a charclass, .$^*+() have a special meaning and need to be escaped to match literally.

allows only the a-zA-Z0-9 characters and .!@#$%^&*()_+-=

Put them in a character class then, let them repeat and require to match the whole string with them by anchors:

var regex = /^[a-zA-Z0-9!@#$%\^&*)(+=._-]*$/

How to get the browser language using JavaScript

Try this script to get your browser language

_x000D_
_x000D_
<script type="text/javascript">_x000D_
var userLang = navigator.language || navigator.userLanguage; _x000D_
alert ("The language is: " + userLang);_x000D_
</script>
_x000D_
_x000D_
_x000D_

Cheers

Can iterators be reset in Python?

list(generator()) returns all remaining values for a generator and effectively resets it if it is not looped.

Changing image size in Markdown

One might draw on the alt attribute that can be set in almost all Markdown implementations/renderes together with CSS-selectors based on attribute values. The advantage is that one can easily define a whole set of different picture sizes (and further attributes).

Markdown:

![minipic](mypic.jpg)

CSS:

img[alt="minipic"] { 
  max-width:  20px; 
  display: block;
}

correct way of comparing string jquery operator =

First of all you should use double "==" instead of "=" to compare two values. Using "=" You assigning value to variable in this case "somevar"

How to express a One-To-Many relationship in Django

django is smart enough. Actually we don't need to define oneToMany field. It will be automatically generated by django for you :-). We only need to define foreignKey in related table. In other words, we only need to define ManyToOne relation by using foreignKey.

class Car(models.Model):
    // wheels = models.oneToMany() to get wheels of this car [**it is not required to define**].


class Wheel(models.Model):
    car = models.ForeignKey(Car, on_delete=models.CASCADE)  

if we want to get the list of wheels of particular car. we will use python's auto generated object wheel_set. For car c you will use c.wheel_set.all()

Passing null arguments to C# methods

From C# 2.0:

private void Example(int? arg1, int? arg2)
{
    if(arg1 == null)
    {
        //do something
    }
    if(arg2 == null)
    {
        //do something else
    }
}

Trouble setting up git with my GitHub Account error: could not lock config file

I've gotten this error when a lock file exists for gitconfig. Try and find and remove .gitconfig.lock (on my linux box it was in my home dir)

How can I show line numbers in Eclipse?

Go to Windows ? Preferences ? General ? Text Editors ? Show numberlines. Click OK, then Apply changes. Then it will show the line count automatically.

How to get text with Selenium WebDriver in Python

The answer is:

driver.find_element_by_class_name("ctsymbol").text

How do I access call log for android?

Before considering making Read Call Log or Read SMS permissions a part of your application I strongly advise you to have a look at this policy of Google Play Market: https://support.google.com/googleplay/android-developer/answer/9047303?hl=en

Those permissions are very sensitive and you will have to prove that your application needs them. But even if it really needs them Google Play Support team may easily reject your request without proper explanations.

This is what happened to me. After providing all the needed information along with the Demonstration video of my application it was rejected with the explanation that my "account is not authorized to provide a certain use case solution in my application" (the list of use cases they may consider as an exception is listed on that Policy page). No link to any policy statement was provided to explain what it all means. Basically they just judged my app as not to go without proper explanation.

I wish you good luck of cause with your applications guys but be careful.

How to sort a Ruby Hash by number value?

Already answered but still. Change your code to:

metrics.sort {|a1,a2| a2[1].to_i <=> a1[1].to_i }

Converted to strings along the way or not, this will do the job.

Create a string with n characters

The for loop will be optimized by the compiler. In such cases like yours you don't need to care about optimization on your own. Trust the compiler.

BTW, if there is a way to create a string with n space characters, than it's coded the same way like you just did.

scroll up and down a div on button click using jquery

To solve your other problem, where you need to set scrolled if the user scrolls manually, you'd have to attach a handler to the window scroll event. Generally this is a bad idea as the handler will fire a lot, a common technique is to set a timeout, like so:

var timer = 0;
$(window).scroll(function() {
  if (timer) {
    clearTimeout(timer);
  }
  timer = setTimeout(function() {
    scrolled = $(window).scrollTop();
  }, 250);
});

Casting to string in JavaScript

There are differences, but they are probably not relevant to your question. For example, the toString prototype does not exist on undefined variables, but you can cast undefined to a string using the other two methods:

?var foo;

?var myString1 = String(foo); // "undefined" as a string

var myString2 = foo + ''; // "undefined" as a string

var myString3 = foo.toString(); // throws an exception

http://jsfiddle.net/f8YwA/

How to integrate SAP Crystal Reports in Visual Studio 2017

Please wait Support Pack 21 in September 2017

UPDATE: More info

https://wiki.scn.sap.com/wiki/display/BOBJ/Crystal+Reports%2C+Developer+for+Visual+Studio+Downloads

VS 2017 - Tested opening existing app and it works, CR for VS is not integrated into the app so no new CR projects available- should be fully integrated in SP 21

About release

Link: https://answers.sap.com/questions/168439/crystal-report-for-vs-2017.html

Moderator Don Williams said:

Not supported yet, I tried to get it into SP 20 but due to time constraints DEV can't get it into VS until SP 21, due out in September time...

Get ASCII value at input word

char a='a';
char A='A';
System.out.println((int)a +" "+(int)A);

Output:
97 65

Is module __file__ attribute absolute or relative?

__file__ is absolute since Python 3.4, except when executing a script directly using a relative path:

Module __file__ attributes (and related values) should now always contain absolute paths by default, with the sole exception of __main__.__file__ when a script has been executed directly using a relative path. (Contributed by Brett Cannon in bpo-18416.)

Not sure if it resolves symlinks though.

Example of passing a relative path:

$ python script.py

How to display my application's errors in JSF?

I tried this as a best guess, but no luck:

It looks right to me. Have you tried setting a message severity explicitly? Also I believe the ID needs to be the same as that of a component (i.e., you'd need to use newPassword1 or newPassword2, if those are your IDs, and not newPassword as you had in the example).

FacesContext.getCurrentInstance().addMessage("newPassword1", 
                    new FacesMessage(FacesMessage.SEVERITY_ERROR, "Error Message"));

Then use <h:message for="newPassword1" /> to display the error message on the JSF page.

How to Test Facebook Connect Locally

You don't have to do anything difficult!

Facebook ? Settings ? Basic:
write "localhost" in the "App Domains" field then click on "+Add Platform" choose "Web Site".

After that, in the "Site Url" field write your localhost url
(e.g.: http://localhost:1337/something).

This will allow you to test your facebook plugins locally.

Change a column type from Date to DateTime during ROR migration

There's a change_column method, just execute it in your migration with datetime as a new type.

change_column(:my_table, :my_column, :my_new_type)

Is there an SQLite equivalent to MySQL's DESCRIBE [table]?

If you're using a graphical tool. It shows you the schema right next to the table name. In case of DB Browser For Sqlite, click to open the database(top right corner), navigate and open your database, you'll see the information populated in the table as below.

enter image description here

right click on the record/table_name, click on copy create statement and there you have it.

Hope it helped some beginner who failed to work with the commandline.

How to rename a file using svn?

Using TortoiseSVN worked easily on Windows for me.

http://tortoisesvn.net/

Right click file -> TortoiseSVN menu -> Repo-browser -> right click file in repository -> rename -> press Enter -> click Ok

Using SVN 1.8.8 TortoiseSVN version 1.8.5