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Why can't R's ifelse statements return vectors?
...tors, you will get longer results:
> ifelse(c(TRUE, FALSE), c(1, 2), c(3, 4))
[1] 1 4
So ifelse is intended for the specific purpose of testing a vector of booleans and returning a vector of the same length, filled with elements taken from the (vector) yes and no arguments.
It is a common con...
Extract elements of list at odd positions
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232
Solution
Yes, you can:
l = L[1::2]
And this is all. The result will contain the elements pl...
npm install vs. update - what's the difference?
...res "1.0" -> "1.1"
"already-installed-semver-module": "^1.4.3" // ignores "1.4.3" -> "1.5.2"
"already-installed-versioned-module": "3.4.1" // ignores ignores
"not-yet-installed-versionless-module": "*", // installs installs
"not-yet-installed-semver-module...
How to check whether a pandas DataFrame is empty?
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edited Dec 15 '17 at 17:37
Dave Thomas
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answere...
Changing the color of the axis, ticks and labels for a plot in matplotlib
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3 Answers
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What do (lambda) function closures capture?
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163
Your second question has been answered, but as for your first:
what does the closure capture...
Java JUnit: The method X is ambiguous for type Y
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3 Answers
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How can I select item with class within a DIV?
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answered Aug 3 '11 at 21:52
David says reinstate MonicaDavid says reinstate Monica
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`levels
...ion, @Marek posted the following solution:
https://stackoverflow.com/a/10432263/636656
4 Answers
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