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How do I write the 'cd' command in a makefile?
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falstrofalstro
30.6k88 gold badges6565 silver badges8585 bronze badges
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Remove an entire column from a data.frame in R
...enome <- NULL
> head(Data)
chr region
1 chr1 CDS
2 chr1 exon
3 chr1 CDS
4 chr1 exon
5 chr1 CDS
6 chr1 exon
As pointed out in the comments, here are some other possibilities:
Data[2] <- NULL # Wojciech Sobala
Data[[2]] <- NULL # same as above
Data <- Data[,-2] ...
How to convert integer to string in C? [duplicate]
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3 Answers
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How to check if a user is logged in (how to properly use user.is_authenticated)?
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530
Update for Django 1.10+:
is_authenticated is now an attribute in Django 1.10.
The method was re...
Batch file: Find if substring is in string (not in a file)
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edited Jul 13 '17 at 2:27
answered Aug 10 '11 at 4:47
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How to delete a file after checking whether it exists
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394
This is pretty straightforward using the File class.
if(File.Exists(@"C:\test.txt"))
{
Fi...
Which is faster: while(1) or while(2)?
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23 Answers
23
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RVM: Uninstalling all gems of a gemset
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answered Jan 14 '11 at 17:39
Andy LindemanAndy Lindeman
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Bash: Copy named files recursively, preserving folder structure
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edited Oct 30 '09 at 15:28
answered Oct 30 '09 at 15:00
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