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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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Codeigniter - no input file specified

I am a beginner in Codeigniter and I saw a CI tutorial and was just trying to do a simple thing. I downloaded the CI and added this file to controller directory, but it won't work. ...
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What is the difference between “long”, “long long”, “long int”, and “long long int” in C++?

I am transitioning from Java to C++ and have some questions about the long data type. In Java, to hold an integer greater than 2 32 , you would simply write long x; . However, in C++, it seems that long is both a data type and a modifier. ...
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What is the difference between PS1 and PROMPT_COMMAND

...oc page: http://www.gnu.org/software/bash/manual/bashref.html PROMPT_COMMAND If set, the value is interpreted as a command to execute before the printing of each primary prompt ($PS1). I never used it, but I could have used this back when I only had sh. ...
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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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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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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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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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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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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...