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Opposite of %in%: exclude rows with values specified in a vector
A categorical variable V1 in a data frame D1 can have values represented by the letters from A to Z. I want to create a subset D2, which excludes some values, say, B, N and T. Basically, I want a command which is the opposite of %in%
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How to select multiple rows filled with constants?
Selecting constants without referring to a table is perfectly legal in an SQL statement:
15 Answers
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How to find Unused Amazon EC2 Security groups
I'm try to find a way to determine orphan security groups so I can clean up and get rid of them. Does anyone know of a way to discover unused security groups.
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How do I create a multiline Python string with inline variables?
I am looking for a clean way to use variables within a multiline Python string. Say I wanted to do the following:
7 Answers...
Iterating over every two elements in a list
How do I make a for loop or a list comprehension so that every iteration gives me two elements?
21 Answers
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How can I get the list of files in a directory using C or C++?
How can I determine the list of files in a directory from inside my C or C++ code?
26 Answers
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Is gettimeofday() guaranteed to be of microsecond resolution?
I am porting a game, that was originally written for the Win32 API, to Linux (well, porting the OS X port of the Win32 port to Linux).
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Check free disk space for current partition in bash
I am writing an installer in bash. The user will go to the target directory and runs the install script, so the first action should be to check that there is enough space. I know that df will report all file systems, but I was wondering if there was a way to get the free space just for the partition...
How to create a Custom Dialog box in android?
I want to create a custom dialog box like below
22 Answers
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How can I open several files at once in Vim?
Is there a way to open all the files in a directory from within Vim? So a :command that would say in effect "Open all the files under /some/path into buffers".
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