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Cartesian product of x and y array points into single array of 2D points

I have two numpy arrays that define the x and y axes of a grid. For example: 13 Answers ...
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WebSockets protocol vs HTTP

There are many blogs and discussions about websocket and HTTP, and many developers and sites strongly advocate websockets, but i still can not understand why. ...
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What is the difference between “JPG” / “JPEG” / “PNG” / “BMP” / “GIF” / “TIFF” Image?

... Yes. They are different file formats (and their file extensions). Wikipedia entries for each of the formats will give you quite a bit of information: JPEG (or JPG, for the file extension; Joint Photographic Experts Group) PNG (Portable Network Graphics) BMP (B...
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How to delete duplicate lines in a file without sorting it in Unix?

...ay then seen[$0] will evaluate to false. The ! is the logical NOT operator and will invert the false to true. Awk will print the lines where the expression evaluates to true. The ++ increments seen so that seen[$0] == 1 after the first time a line is found and then seen[$0] == 2, and so on. Awk eval...
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Check existence of input argument in a Bash shell script

... I like to do it this way, in terse syntax and still POSIX acceptable. [ -z "$1" ] && echo "No argument supplied" I prefer one-liners, as they are easier for me; and it's also faster to check exit value, compared to using if – J. M. Beck...
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Replace all non Alpha Numeric characters, New Lines, and multiple White Space with one Space

...would be [\W_] text.replace(/[\W_]+/g," "); \W is the negation of shorthand \w for [A-Za-z0-9_] word characters (including the underscore) Example at regex101.com share | improve this answer ...
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Hidden features of Python [closed]

...ue In case you're thinking it's doing 1 < x, which comes out as True, and then comparing True < 10, which is also True, then no, that's really not what happens (see the last example.) It's really translating into 1 < x and x < 10, and x < 10 and 10 < x * 10 and x*10 < 100, but...
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How to use sed to replace only the first occurrence in a file?

...r if you prefer' solution. It would also be good to explain the answers - and to make the answer address the question directly, and then generalize, rather than generalize only. But good answer. – Jonathan Leffler Sep 29 '08 at 13:15 ...
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Android Studio Stuck at Gradle Download on create new project

I have installed the new Android Studio . Everything was working fine but when I try to create a new project it gets stuck at downloading Gradle . ...
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What is the difference between range and xrange functions in Python 2.X?

Apparently xrange is faster but I have no idea why it's faster (and no proof besides the anecdotal so far that it is faster) or what besides that is different about ...