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Select first 4 rows of a data.frame in R
...et the rows 5 to 7?
– Bustergun
May 21 '18 at 9:38
You can use the "index" answer pointed out elsewhere. In this situa...
Where to install Android SDK on Mac OS X?
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12 Answers
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How to read data when some numbers contain commas as thousand separator?
..."", and then convert the string to numeric using as.numeric:
y <- c("1,200","20,000","100","12,111")
as.numeric(gsub(",", "", y))
# [1] 1200 20000 100 12111
This was also answered previously on R-Help (and in Q2 here).
Alternatively, you can pre-process the file, for instance with sed in uni...
Parallel.ForEach() vs. foreach(IEnumerable.AsParallel())
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edited Apr 4 '14 at 9:22
svick
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instanceof Vs getClass( )
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edited Feb 3 at 7:23
answered Feb 14 '11 at 7:44
St...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
I have SQL Server 2008 R2 and I want to set a unique column.
4 Answers
4
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Selecting and manipulating CSS pseudo-elements such as ::before and ::after using jQuery
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22 Answers
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Rails render partial with block
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While both of those answers above work (well the example that tony links to anyway) I ended up...
Discard all and get clean copy of latest revision?
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Those steps should be able to be shortened down to:
hg pull
hg update -r MY_BRANCH -C
The -...
“Uncaught TypeError: Illegal invocation” in Chrome
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answered Mar 13 '12 at 3:59
NemoyNemoy
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