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How do I delete rows in a data frame?
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The key idea is you form a set of the rows you want to remove, and keep the complement of that set.
In R, the complement of a set is given by the '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of...
Perl build, unit testing, code coverage: A complete working example
...usr + 0.00 csys = 0.00 CPU)
cover
Reading database from D:/Documents and Settings/LeuchKW/workspace/HelloPerlBuildWorld/cover_db
----------------------------------- ------ ------ ------ ------ ------ ------
File stmt bran cond sub time total
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Parse usable Street Address, City, State, Zip from a string [closed]
... data out from the string.
It's meant for the case when you need to get a set of data mostly in the right fields, or want to provide a shortcut to data entry (letting users paste an address into a textbox rather than tabbing among multiple fields). It is not meant for verifying the deliverability o...
Single script to run in both Windows batch and Linux Bash?
...t forget that any use of $? must be before your next colon : because : resets $? to 0.
:; echo "Hi, I’m ${SHELL}."; exit $?
@ECHO OFF
ECHO I'm %COMSPEC%
A very contrived example of guarding $?:
:; false; ret=$?
:; [ ${ret} = 0 ] || { echo "Program failed with code ${ret}." >&2; exit 1; ...
How to say “should_receive” more times in RSpec
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“Cloning” row or column vectors
... the second section ("repeating columns"), can you explain what the second set of square bracket does, i.e. [[1,2,3]]
– Ant
Jan 9 '17 at 0:51
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How can I pair socks from a pile efficiently?
...pile and distribute it by some other metric (e.g. pattern) into the second set of piles
Recursively apply this scheme until you have distributed all socks onto very small piles that you can visually process immediately
This kind of recursive hash partitioning is actually being done by SQL Server w...
Quick Sort Vs Merge Sort [duplicate]
... than merge sort when the data is stored in memory. However, when the data set is huge and is stored on external devices such as a hard drive, merge sort is the clear winner in terms of speed. It minimizes the expensive reads of the external drive and also lends itself well to parallel computing.
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How to git-svn clone the last n revisions from a Subversion repository?
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See line breaks and carriage returns in editor
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:set list in Vim will show whitespace. End of lines show as '$' and carriage returns usually show as '^M'.
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