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How to shift a column in Pandas DataFrame
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@WaylonWalker That's called rolling in numpy: df['x2'] = np.roll(df['x2'], 1)
– ayhan
Nov 25 '17 at 17:35
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Filtering collections in C#
... ints that are > than 7, Where returns an
// IEnumerable<T> so a call to ToList is required to convert back to a List<T>.
List<int> filteredList = myList.Where( x => x > 7).ToList();
If you can't find the .Where, that means you need to import using System.Linq; at the to...
How to get the previous URL in JavaScript?
... submitting a form?). Specified by DOM Level 2. More here.
window.history allows navigation, but not access to URLs in the session for security and privacy reasons. If more detailed URL history was available, then every site you visit could see all the other sites you'd been to.
If you're dealing...
Stop/Close webcam which is opened by navigator.getUserMedia
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EDIT
Since this answer has been originally posted the browser API has changed.
.stop() is no longer available on the stream that gets passed to the callback.
The developer will have to access the tracks that make up the stream (audio or video) and stop each of th...
RESTful way to create multiple items in one request
I am working on a small client server program to collect orders. I want to do this in a "REST(ful) way".
7 Answers
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Do copyright dates need to be updated? [closed]
...e work.
Therefore, if the claim is based on common law copyright (not formally registered), then the date should be the date of first publication. If the claim is a registered copyright, then the date should be the date claimed in the registration. In cases where the work was substantially revised ...
Store pictures as files or in the database for a web app?
...l include a lot of pictures and hopefully a fair amount of traffic. I do really want to achieve performance.
10 Answers
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Determine if two rectangles overlap each other?
...er to construct rectangles (between 2 and 5): height, width, x-pos, y-pos. All of these rectangles will exist parallel to the x and the y axis, that is all of their edges will have slopes of 0 or infinity.
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Programmatically create a UIView with color gradient
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Objective-C:
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 50)];
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = view.bounds;
gradient.colors = @[(id)[UIColor whiteColor].CGColor, (id)[UIColor blackColor].CGColor];
[v...
How to differ sessions in browser-tabs?
...f I store information in the user session, this information is shared from all the tabs from the same browser. How to differ sessions in the browser-tabs?
In this example:
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