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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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eval command in Bash and its typical uses

After reading the bash man pages and with respect to this post . 10 Answers 10 ...
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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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Android emulator-5554 offline

... order to be assured that your emulator starts working again : Go to cmd and type adb kill-server Go to task manager and find adb in processes. If you find one, right click on it and click on end process tree. In eclipse, go to Window>Android Virtual Device Manager, click on the AVD you want t...
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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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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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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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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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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...