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How to prevent ifelse() from turning Date objects into numeric objects
... 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(): ...
quick random row selection in Postgres
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answered Mar 14 '11 at 10:45
NPENPE
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How do I translate an ISO 8601 datetime string into a Python datetime object? [duplicate]
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How to implement an android:background that doesn't stretch?
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'float' vs. 'double' precision
...d 1 sign bit.
Double precision (double) gives you 52 bits of significand, 11 bits of exponent, and 1 sign bit.
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What is the difference between user variables and system variables?
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edited Apr 11 at 12:34
ahmednabil88
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Comma separator for numbers in R?
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answered Oct 1 '10 at 11:43
Joris MeysJoris Meys
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NSString: isEqual vs. isEqualToString
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edited May 5 '13 at 11:15
Pang
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What is the difference between MediaPlayer and VideoView in Android
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answered Jan 19 '11 at 20:12
mishkinmishkin
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Understanding the ngRepeat 'track by' expression
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ram1993ram1993
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