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What's the fastest way to merge/join data.frames in R?
...he first. If there are duplicates in the second data frame then the match and merge approaches are not the same. Match is, of course, faster since it is not doing as much. In particular it never looks for duplicate keys. (continued after code)
DF1 = data.frame(a = c(1, 1, 2, 2), b = 1:4)
DF2 = da...
how to change any data type into a string in python
...mystring = repr(myvariable) # '4'
This is called "conversion" in python, and is quite common.
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How to keep onItemSelected from firing off on a newly instantiated Spinner?
...ple boolean flag would allow you to detect the rogue first selection event and ignore it.
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Difference between DirectCast() and CType() in VB.NET
.../C++/C# programmer who has just gotten into VB.NET. I generally use CType (and CInt, CBool, CStr) for casts because it is fewer characters and was the first way of casting which I was exposed to, but I am aware of DirectCast and TryCast as well.
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How do you see recent SVN log entries?
Typing svn log spits out an incredibly long, useless list on a command line. I have no idea why that is the default. If I wanted to read (or even could read) 300 entries on the terminal, I wouldn't mind typing svn log --full or something similar.
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What is the difference between HTML tags and ?
...uld like to ask for some simple examples showing the uses of <div> and <span> . I've seen them both used to mark a section of a page with an id or class , but I'm interested in knowing if there are times when one is preferred over the other.
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How does one capture a Mac's command key via JavaScript?
...is not going to be captured by browsers as such.
This is only for the command key on MacOS/keyboards.
Unlike Shift/Alt/Ctrl, the Cmd (“Apple”) key is not considered a modifier key—instead, you should listen on keydown/keyup and record when a key is pressed and then depressed based on event...
Get integer value of the current year in Java
...wer, Calendar would be a fine object to use. I was looking for a one-liner and I didn't think Calendar would have that for me. Proven wrong I am! Thanks!
– karlgrz
Sep 25 '08 at 22:03
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How to execute a file within the python interpreter?
I'm trying to execute a file with python commands from within the interpreter.
11 Answers
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Split files using tar, gz, zip, or bzip2 [closed]
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You can use the split command with the -b option:
split -b 1024m file.tar.gz
It can be reassembled on a Windows machine using @Joshua's answer.
copy /b file1 + file2 + file3 + file4 filetogether
Edit: As @Charlie stated in the comment below, y...