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Measure elapsed time in Swift
...
let start = NSDate()
for index in 1...10000 {
// do nothing
}
let elapsed = start.timeIntervalSinceNow
// elapsed is a negative value.
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Create Git branch with current changes
...the "destructive" effect of a git reset --hard command (it does resets the index and working tree. Any changes to tracked files in the working tree since <commit> are discarded), I would rather go with:
$ git reset --soft HEAD~3 # (2)
This would make sure I'm not losing any private file (n...
Selecting/excluding sets of columns in pandas [duplicate]
...]] where n is the last column of n number of columns, I'm trying negative indexing [[-1]]<- it isn't working :( help!~
– 3kstc
Mar 8 '18 at 3:26
5
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count the frequency that a value occurs in a dataframe column
...requency back to the original dataframe use transform to return an aligned index:
In [41]:
df['freq'] = df.groupby('a')['a'].transform('count')
df
Out[41]:
a freq
0 a 2
1 b 3
2 s 2
3 s 2
4 b 3
5 a 2
6 b 3
[7 rows x 2 columns]
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How to set size for local image using knitr for markdown?
...is the label of the chunk where the plot has been generated, i is the plot index (within this chunk) and ext is the file extension (by default png in RMarkdown documents).
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CSS3 Rotate Animation
...ght:114px;
top:400px;
margin:0 auto;
margin-left:-195px;
z-index:0;
-webkit-transition-duration: 0.8s;
-moz-transition-duration: 0.8s;
-o-transition-duration: 0.8s;
transition-duration: 0.8s;
-webkit-transition-property: -webkit-transform;
-moz-transition-pr...
Cell spacing in UICollectionView
...ionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
return [self getCellSize:indexPath]; // will be w120xh100 or w190x100
// if the width is higher, only one image will be shown in a line
}
#pragma mark collection view cell paddin...
Is there a way to make R beep/play a sound at the end of a script?
...ve it tweet when it's done: http://cran.r-project.org/web/packages/twitteR/index.html
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CSS selector for “foo that contains bar”? [duplicate]
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No, what you are looking for would be called a parent selector. CSS has none; they have been proposed multiple times but I know of no existing or forthcoming standard including them. You are correct that you would need to use something like jQuery or use additiona...
Remove folder and its contents from git/GitHub's history
...od I use to completely remove a directory from the git history using the --index-filter option, which runs much quicker:
# Make a fresh clone of YOUR_REPO
git clone YOUR_REPO
cd YOUR_REPO
# Create tracking branches of all branches
for remote in `git branch -r | grep -v /HEAD`; do git checkout --tra...