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How do I replace NA values with zeros in an R dataframe?
I have a data frame and some columns have NA values.
21 Answers
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Display help message with python argparse when script is called without any arguments
This might be a simple one. Assume I have a program that uses argparse to process command line arguments/options. The following will print the 'help' message:
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Introducing FOREIGN KEY constraint may cause cycles or multiple cascade paths - why?
... where Stage is involved will have cascading delete enabled by default. It means, if you delete a Stage entity
the delete will cascade directly to Side
the delete will cascade directly to Card and because Card and Side have a required one-to-many relationship with cascading delete enabled by defau...
Programmatically align a toolbar on top of the iPhone keyboard
...of the iPhone keyboard (as in iPhone Safari when you're navigating form elements, for example).
7 Answers
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Passing parameters to addTarget:action:forControlEvents
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action:@selector(switchToNewsDetails:)
You do not pass parameters to switchToNewsDetails: method here. You just create a selector to make button able to call it when certain action occurs (touch up in your case). Controls can use 3 types of selectors to respond to actions, all of the...
Django. Override save for model
...picture added or just description updated, so I can skip rescaling every time the model is saved?
7 Answers
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How to enable MySQL Query Log?
How do I enable the MySQL function that logs each SQL query statement received from clients and the time that query statement has submitted?
Can I do that in phpmyadmin or NaviCat?
How do I analyse the log?
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Error: “dictionary update sequence element #0 has length 1; 2 is required” on Django 1.4
I have an error message on django 1.4:
12 Answers
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Quick Sort Vs Merge Sort [duplicate]
Why might quick sort be better than merge sort ?
11 Answers
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How to discard local changes in an SVN checkout?
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Just use the svn revert command, for example:
svn revert some_file.php
It is (as every other svn command) well documented in the svnbook resource or man page, or even with the svn help command.
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