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Random row selection in Pandas dataframe
...me(x, n):
return x.ix[random.sample(x.index, n)]
Note: As of Pandas v0.20.0, ix has been deprecated in favour of loc for label based indexing.
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Using HTML5/Canvas/JavaScript to take in-browser screenshots
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+50
JavaScript can read the DOM and render a fairly accurate representation of that using canvas. I have been working on a script which co...
How to resolve “must be an instance of string, string given” prior to PHP 7?
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205
Prior to PHP 7 type hinting can only be used to force the types of objects and arrays. Scalar t...
Sass calculate percent minus px
... from one unit to the next. Sass has no way of knowing exactly how wide "100%" is in terms of pixels or any other unit. That's something only the browser knows.
You need to use calc() instead. Check browser compatibility on Can I use...
.foo {
height: calc(25% - 5px);
}
If your values are...
What does the caret operator (^) in Python do?
...y one) of the operands (evaluates to) true.
To demonstrate:
>>> 0^0
0
>>> 1^1
0
>>> 1^0
1
>>> 0^1
1
To explain one of your own examples:
>>> 8^3
11
Think about it this way:
1000 # 8 (binary)
0011 # 3 (binary)
---- # APPLY XOR ('vertically')
10...
How to synchronize a static variable among threads running different instances of a class in Java?
...s on the class object.
public class Test {
private static int count = 0;
public static synchronized void incrementCount() {
count++;
}
}
Explicitly synchronize on the class object.
public class Test {
private static int count = 0;
public void incrementCount() {
...
Reading a string with scanf
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140
An array "decays" into a pointer to its first element, so scanf("%s", string) is equivalent to s...
Check whether number is even or odd
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204
You can use the modulus operator, but that can be slow. If it's an integer, you can do:
if ( (...
Showing the same file in both columns of a Sublime Text window
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edited Oct 22 '16 at 3:40
answered May 30 '14 at 23:33
Ma...
How do I specify multiple targets in my podfile for my Xcode project?
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CocoaPods 1.0 has changed the syntax for this. It now looks like this:
def shared_pods
pod 'SSKeychain', '~> 0.1.4'
pod 'INAppStoreWindow', :head
pod 'AFNetworking', '1.1.0'
pod 'Reachability', '~> 3.1.0'
pod ...