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Global access to Rake DSL methods is deprecated
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Determine the data types of a data frame's columns
...is makes the example exactly reproducible
my.data <- data.frame(y=rnorm(5),
x1=c(1:5),
x2=c(TRUE, TRUE, FALSE, FALSE, FALSE),
X3=letters[1:5])
@Wilmer E Henao H's solution is very streamlined:
sapply(my.data, class)
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Delete element in a slice
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flornquake
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answered Jul 29 '14 at 21:47
davedave
46.2...
Find XOR of all numbers in a given range
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Shuffle two list at once with same order
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answered Apr 25 '14 at 9:45
sshashank124sshashank124
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What is the best way to compute trending topics or tags?
...rn (obs - avg) / std
Sample Output
>>> zscore(12, [2, 4, 4, 4, 5, 5, 7, 9])
3.5
>>> zscore(20, [21, 22, 19, 18, 17, 22, 20, 20])
0.0739221270955
>>> zscore(20, [21, 22, 19, 18, 17, 22, 20, 20, 1, 2, 3, 1, 2, 1, 0, 1])
1.00303599234
>>> zscore(2, [21, 22, 19, 18...
Difference between exit(0) and exit(1) in Python
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Extract elements of list at odd positions
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Dynamically select data frame columns using $ and a character value
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You can't do that kind of subsetting with $. In the source code (R/src/main/subset.c) it states:...