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What is the difference between exit(0) and exit(1) in C?
...ccessful program termination & it is fully portable, While
exit(1) (usually) indicates unsucessful termination. However, it's usage is non-portable.
Note that the C standard defines EXIT_SUCCESS and EXIT_FAILURE to return termination status from a C program.
0 and EXIT_SUCCESS are the values s...
Changing a specific column name in pandas DataFrame
...
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...
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...
How do I get Gridview to render THEAD?
...during postback and placed the code in the databound event which addressed all scenarios.
– James Westgate
Jun 10 '15 at 8:12
...
Make a link in the Android browser start up my app?
...o look at the <intent-filter> element of your Mainfest file. Specifically, take a look at the documentation for the <data> sub-element.
Basically, what you'll need to do is define your own scheme. Something along the lines of:
<intent-filter>
<data android:scheme="anton" /...
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...
SVN: Is there a way to mark a file as “do not commit”?
...rtoiseSVN has a built in changelist, "ignore-on-commit", which is automatically excluded from commits. The command-line client does not have this, so you need to use multiple changelists to accomplish this same behavior (with caveats):
one for work you want to commit [work]
one for things you want...
Why is creating a Thread said to be expensive?
... there is a fair bit of work involved:
A large block of memory has to be allocated and initialized for the thread stack.
System calls need to be made to create / register the native thread with the host OS.
Descriptors need to be created, initialized and added to JVM-internal data structures.
It...
Why was the switch statement designed to need a break?
...
Many answers seem to focus on the ability to fall through as the reason for requiring the break statement.
I believe it was simply a mistake, due largely because when C was designed there was not nearly as much experience with how these constructs would be used.
Peter ...
What's the simplest way to test whether a number is a power of 2 in C++?
...
so basically (n>0 && ((n & (n-1)) == 0))
– Saurabh Goyal
Jul 10 '16 at 8:06
1
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