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Changing a specific column name in pandas DataFrame
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A one liner does exist:
In [27]: df=df.rename(columns = {'two':'new_name'})
In [28]: df
Out[28]:
one three new_name
0 1 a 9
1 2 b 8
2 3 c 7
3 4 d 6
4 5 e 5
Following is the docstring for the rename method.
De...
Java Equivalent of C# async/await?
I am a normal C# developer but occasionally I develop application in Java. I'm wondering if there is any Java equivalent of C# async/await?
In simple words what is the java equivalent of:
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How to convert a byte array to a hex string in Java?
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From the discussion here, and especially this answer, this is the function I currently use:
private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray();
public static String bytesToHex(byte[] bytes) {
char[] hexChars = new char[bytes.length * 2...
How can I tell if I'm running in 64-bit JVM or 32-bit JVM (from within a program)?
... 64 bit version is running, you'll get a message like:
java version "1.6.0_18"
Java(TM) SE Runtime Environment (build 1.6.0_18-b07)
Java HotSpot(TM) 64-Bit Server VM (build 16.0-b13, mixed mode)
A 32 bit version will show something similar to:
java version "1.6.0_41"
Java(TM) SE Runtime Environm...
http to https apache redirection
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I have actually followed this example and it worked for me :)
NameVirtualHost *:80
<VirtualHost *:80>
ServerName mysite.example.com
Redirect permanent / https://mysite.example.com/
</VirtualHost>
<VirtualHost _de...
Is there a built in function for string natural sort?
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There is a third party library for this on PyPI called natsort (full disclosure, I am the package's author). For your case, you can do either of the following:
>>> from natsort import natsorted, ns
>>> x = ['Elm11', 'Elm12', 'Elm2', 'elm0', 'elm1', 'elm1...
Defining a variable with or without export
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Specifically export makes the variable available to child processes via the environment.
– Beano
Jul 21 '09 at 13:35
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Paging UICollectionView by cells, not screen
...nformance and set a value for pageWidth:
func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
let pageWidth = // The width your page should have (plus a possible margin)
let proportionalOffset = collectionView.contentOffset.x / pageWidth
indexOfCellBeforeDragging = Int(round(p...
Is there a HTML opposite to ?
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Not allowed in the xhtml standard at least.
– Dykam
Aug 4 '09 at 19:56
29
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Why does viewWillAppear not get called when an app comes back from the background?
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In other words, if someone looks at another application or takes a phone call, then switches back to your app which was earlier on backgrounded, your UIViewController which was already visible when you left your app 'doesn't care' so to speak -- as far as it is concerned, it's never disappeared and...