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Preventing form resubmission
Page one contains an HTML form. Page two - the code that handles the submitted data.
12 Answers
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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
I am working with the pandas library and I want to add two new columns to a dataframe df with n columns (n > 0).
These new columns result from the application of a function to one of the columns in the dataframe.
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Simulate airplane mode in iPhone Simulator
... emulate the iPhone; it's just an environment for Mac apps to link against and look like an iPhone. So you need a way, at the system layer, to restrict an app from talking to the network. Unix doesn't provide that; it would almost certainly need kernel support to get it. You could do it more easily ...
How does one reorder columns in a data frame?
...mns like so df[,c(1,2,3,4)].
Note the first comma means keep all the rows, and the 1,2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
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How to replace a hash key with another key
...akes some time to tell what it is really doing. Your solution is in other hand simple and descriptive.
– Lucas
Nov 13 '14 at 18:55
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Bash: infinite sleep (infinite blocking)
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sleep infinity does exactly what it suggests and works without cat abuse.
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Postgresql GROUP_CONCAT equivalent?
I have a table and I'd like to pull one row per id with field values concatenated.
7 Answers
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Markdown vs markup - are they related?
...ark-up is a term from print editing - the editor would go through the text and add annotations (i.e. this in italic, that in bold) for the printers to use when producing the final version. This was called marking up the text.
A computer mark-up language is just a standardised short-hand for these s...
How to slice an array in Bash
...e - is necesssary
Note that the fact that "a b c" is one array element (and that it contains an extra space) is preserved.
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What is the difference between “word-break: break-all” versus “word-wrap: break-word” in CSS
...k-all is for requiring a particular behaviour with CJK (Chinese, Japanese, and Korean) text, whereas word-wrap: break-word is the more general, non-CJK-aware, behaviour.
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