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How to prevent ifelse() from turning Date objects into numeric objects
...d class of the inputs.
library(data.table)
dates <- fifelse(dates == '2011-01-01', dates - 1, dates)
str(dates)
# Date[1:5], format: "2010-12-31" "2011-01-02" "2011-01-03" "2011-01-04" "2011-01-05"
dplyr::if_else
From dplyr 0.5.0 release notes:
[if_else] have stricter semantics that ifelse():...
Python multiprocessing pool.map for multiple arguments
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edited Oct 10 '17 at 16:11
answered Mar 26 '11 at 14:36
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Replace all non Alpha Numeric characters, New Lines, and multiple White Space with one Space
... [A-Za-z0-9_] word characters (including the underscore)
Example at regex101.com
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Maven Install on Mac OS X
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OS X prior to Mavericks (10.9) actually comes with Maven 3 built in.
If you're on OS X Lion, you won't have java installed by default. Just run java by itself and it'll prompt you to install it.
Assuming qualifications are met, run mvn -version ...
Preferred method to store PHP arrays (json_encode vs serialize)
...ly %01.2f%% faster than serialize()\n", ($serializeTime / $jsonTime - 1) * 100);
}
else if ($serializeTime < $jsonTime ) {
printf("serialize() was roughly %01.2f%% faster than json_encode()\n", ($jsonTime / $serializeTime - 1) * 100);
} else {
echo "Impossible!\n";
}
function fillArray( ...
print call stack in C or C++
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answered Oct 10 '10 at 10:25
Idan KIdan K
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How do I log a Python error with debug information?
...ve it something.
– ArtOfWarfare
Jun 10 '18 at 3:00
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How can I use “sizeof” in a preprocessor macro?
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answered Nov 2 '10 at 15:35
James McNellisJames McNellis
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How can I open multiple files using “with open” in Python?
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As of Python 2.7 (or 3.1 respectively) you can write
with open('a', 'w') as a, open('b', 'w'...