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How does one reorder columns in a data frame?
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Your dataframe has four columns 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 do an update + join in PostgreSQL?
Basically, I want to do this:
9 Answers
9
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How to get the size of a string in Python?
For example, I get a string:
5 Answers
5
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Android search with Fragments
...an Activity, not a Fragment; thus, implementing a search interface that is completely independent of an Activity is not possible, as it would require changes to the underlying system itself. Check out the source code for the SearchableInfo class if you don't believe me :).
That being said, it does...
Convert DOS line endings to Linux line endings in Vim
If I open files I created in Windows, the lines all end with ^M .
How do I delete these characters all at once?
26 Answers...
In C#, why is String a reference type that behaves like a value type?
...istics of a value type such as being immutable and having == overloaded to compare the text rather than making sure they reference the same object.
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Get program execution time in the shell
I want to execute something in a linux shell under a few different conditions, and be able to output the execution time of each execution.
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Haskell offline documentation?
...ttp://hackage.haskell.org/package/hoogle
Usage instructions are at http://www.haskell.org/haskellwiki/Hoogle#Command_Line_Search_Flags.
Usage:
$ hoogle --help
Hoogle v4.2.8, (C) Neil Mitchell 2004-2011
http://haskell.org/hoogle
hoogle [COMMAND] ... [OPTIONS]
Commands:
[search] Perform a sear...
Fixing JavaScript Array functions in Internet Explorer (indexOf, forEach, etc.) [closed]
... implementations (eg. for indexOf). They're generally rigorously standards-compliant, even to the extent of explicitly checking the types of all the arguments.
Unfortunately whilst it is clear that the authors regard this code as trivial and freely-usable, there doesn't seem to be an explicit licen...
omp parallel vs. omp parallel for
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allowed for the parallel and worksharing contructs.
Taken from http://www.openmp.org/mp-documents/OpenMP3.0-SummarySpec.pdf
The specs for OpenMP are here:
https://openmp.org/specifications/
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