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Group by multiple columns in dplyr, using string vector input
...
Since this question was posted, dplyr added scoped versions of group_by (documentation here). This lets you use the same functions you would use with select, like so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = s...
How do I export UIImage array as a movie?
...catorDefault, frameSize.width,
frameSize.height, kCVPixelFormatType_32ARGB, (CFDictionaryRef) options,
&pxbuffer);
NSParameterAssert(status == kCVReturnSuccess && pxbuffer != NULL);
CVPixelBufferLockBaseAddress(pxbuffer, 0);
void *pxdata = CVPixelBufferGetBa...
What does the 'b' character do in front of a string literal?
...
Actually, if you've imported unicode_literals from __future__, this will "reverse" the behavior for this particular string (in Python 2.x)
– Romuald Brunet
Mar 14 '13 at 16:27
...
nonlocal keyword in Python 2.x
... @BobStein Sorry, I don't really understand what you mean. But by adding __slots__ = () and creating an object instead of using the class, e.g. context.z = 3 would raise an AttributeError. It is possible for all classes, unless they inherit from a class not defining slots.
– ...
Detect Android phone via Javascript / jQuery
...w.location = 'http://android.davidwalsh.name';
}
PHP:
$ua = strtolower($_SERVER['HTTP_USER_AGENT']);
if(stripos($ua,'android') !== false) { // && stripos($ua,'mobile') !== false) {
header('Location: http://android.davidwalsh.name');
exit();
}
Edit : As pointed out in some comments...
addEventListener vs onclick
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@Gaurav_soni No. The name of the function and all the code it contains are already exposed in the javascript file, which is in plaintext. Anyone can open a web console and execute or manipulate any javascript. If your javascript con...
Passing current scope to an AngularJS Service
...In the service constructor you can assign the scope to something like this._scope and then reference the scope within the service!
angular.module('blah').controller('BlahCtrl', function($scope, BlahService) {
$scope.someVar = 4;
$scope.blahService = new blahService($scope);
});
angular....
Is it pythonic to import inside functions?
...te the circular dependency)
Inserting a pdb breakpoint: import pdb; pdb.set_trace() This is handy b/c I don't want to put import pdb at the top of every module I might want to debug, and it easy to remember to remove the import when I remove the breakpoint.
Outside of these two cases, it's a good ...
What is a NullReferenceException, and how do I fix it?
...ic class Form1
{
private Customer customer;
private void Form1_Load(object sender, EventArgs e)
{
Customer customer = new Customer();
customer.Name = "John";
}
private void Button_Click(object sender, EventArgs e)
{
MessageBox.Show(customer....
Why split the tag when writing it with document.write()?
...ecx.images-amazon.com/images/G/01/javascripts/lib/jquery/jquery-1.2.6.pack._V265113567_.js"></script>');
}
// -->
</script>
...but to be honest, using document.write is not something I would consider best practice. Why not manipulating the DOM directly?
<script type="...