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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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Confusion between factor levels and factor labels

There seems to be a difference between levels and labels of a factor in R. Up to now, I always thought that levels were the 'real' name of factor levels, and labels were the names used for output (such as tables and plots). Obviously, this is not the case, as the following example shows: ...
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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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Retina displays, high-res background images

...wer, here is the retina detection query I tend to use: @media only screen and (-webkit-min-device-pixel-ratio: 2), only screen and ( min--moz-device-pixel-ratio: 2), only screen and ( -o-min-device-pixel-ratio: 2/1), only screen and ( min-device-pixel-ratio: 2), only screen and ( ...
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Label encoding across multiple columns in scikit-learn

I'm trying to use scikit-learn's LabelEncoder to encode a pandas DataFrame of string labels. As the dataframe has many (50+) columns, I want to avoid creating a LabelEncoder object for each column; I'd rather just have one big LabelEncoder objects that works across all my columns of data. ...
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What is the difference between '@' and '=' in directive scope in AngularJS?

I've read the AngularJS documentation on the topic carefully, and then fiddled around with a directive. Here's the fiddle . ...
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Understanding ibeacon distancing

...estimates. While the distance estimates are useful, they are not perfect, and require that you control for other variables. Be sure you read up on the complexities and limitations before misusing this. When we were building the Android iBeacon library, we had to come up with our own independent a...
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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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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...