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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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System.IO.Packaging
I have my project set to .NET Framework 4.0. When I add System.IO.Packaging , it says that it doesn't exist. It also doesn't show up when I try to add it as a reference to the project.
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Cleanest and most Pythonic way to get tomorrow's date?
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edited Oct 1 '09 at 22:52
Esteban Küber
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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...
'parent.relativePath' points at my com.mycompany:MyProject instead of org.apache:apache - Why?
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260
Add an empty <relativePath> to <parent> so that it resolves the parent pom from the ...
Standard deviation of a list
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Since Python 3.4 / PEP450 there is a statistics module in the standard library, which has a method stdev for calculating the standard deviation of iterables like yours:
>>> A_rank = [0.8, 0.4, 1.2, 3.7, 2.6, 5.8]
>>> import statis...
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() {
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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...
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...
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...