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Referring to the null object in Python
...n addition to False itself, the property is shared by empty lists, tuples, sets, dicts, strings, as well as 0, and all objects from classes that implement the __bool__() magic method to return False.
>>> bool(None)
False
>>> not None
True
>>> bool([])
False
>>> n...
Asp.NET Web API - 405 - HTTP verb used to access this page is not allowed - how to set handler mappi
I wrote REST service using ASP.NET Web API.
I'm trying to send HttpDelete request, however I get the following error:
14 An...
How to Reverse Fragment Animations on BackStack?
...
According to the android documentation for custom animation:
Change:
ft.setCustomAnimations(R.anim.slide_in, R.anim.hyperspace_out);
To:
ft.setCustomAnimations(R.anim.slide_in, R.anim.hyperspace_out, R.anim.hyperspace_in, R.anim.slide_out );
and now the backstack animates - In reverse!!
...
Strange \n in base64 encoded string in Ruby
... editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
...
What is copy-on-write?
I would like to know what copy-on-write is and what it is used for? The term 'copy-on-write array' is mentioned several times in the Sun JDK tutorials but I didn't understand what it meant.
...
Android SDK installation doesn't find JDK
...
Doesn't work for me on Windows 7 x64. I'm not joking. I set JAVA_HOME and I tried clicking back and next several times, but it's still not working. Neither does running SDK Manager.exe from the archive and I am positive I have JDK 7 installed (even ran the installer again and it t...
How to count certain elements in array?
...ict stresses it uses the == operator.)
Also consider using your own multiset data structure (e.g. like python's 'collections.Counter') to avoid having to do the counting in the first place.
class Multiset extends Map {
constructor(...args) {
super(...args);
}
add(elem) {
...
Correct way to convert size in bytes to KB, MB, GB in JavaScript
...lector('p'),
input = document.querySelector('input');
function setText(v){
p.innerHTML = formatBytes(v);
}
// bind 'input' event
input.addEventListener('input', function(){
setText( this.value )
})
// set initial text
setText(input.value);
<input type="text" value="1...
Git for beginners: The definitive practical guide
...sitory: this has one gotcha: if you have the environment variable $GIT_DIR set in your current shell, git will ignore your current location and use the repository at $GIT_DIR. I should know, I lost an hour to that yesterday.
– sanmiguel
Mar 1 '12 at 12:17
...
What is :: (double colon) in Python when subscripting sequences?
...w???"... Read on! (We can do this in a 2-step approach)
Step 1 - Obtain subset
Specify the "start index" and "end index" in both row-wise and column-wise directions.
In code:
In [5]: X2 = X[2:9,3:8]
In [6]: X2
Out[6]:
array([[23, 24, 25, 26, 27],
[33, 34, 35, 36, 37],
[43, 44, 45, 46...