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Replacing NAs with latest non-NA value

...ry(zoo) az <- zoo(1:6) bz <- zoo(c(2,NA,1,4,5,2)) na.locf(bz) 1 2 3 4 5 6 2 2 1 4 5 2 na.locf(bz, fromLast = TRUE) 1 2 3 4 5 6 2 1 1 4 5 2 cz <- zoo(c(NA,9,3,2,3,2)) na.locf(cz) 2 3 4 5 6 9 3 2 3 2 shar...
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Remove empty elements from an array in Javascript

... to remove null or undefined values: var array = [0, 1, null, 2, "", 3, undefined, 3,,,,,, 4,, 4,, 5,, 6,,,,]; var filtered = array.filter(function (el) { return el != null; }); console.log(filtered); It will depend on what you consider to be "empty" for example, if you were d...
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What does -1 mean in numpy reshape?

...numpy allow us to give one of new shape parameter as -1 (eg: (2,-1) or (-1,3) but not (-1, -1)). It simply means that it is an unknown dimension and we want numpy to figure it out. And numpy will figure this by looking at the 'length of the array and remaining dimensions' and making sure it satisfi...
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Grouping functions (tapply, by, aggregate) and the *apply family

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Validating IPv4 addresses with regexp

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How can I get nth element from a list?

... Look here, the operator used is !!. I.e. [1,2,3]!!1 gives you 2, since lists are 0-indexed. share | improve this answer | follow |...
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How to slice an array in Bash

... 317 See the Parameter Expansion section in the Bash man page. A[@] returns the contents of the arr...
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How to check if two arrays are equal with JavaScript? [duplicate]

... C. Tewalt 2,02322 gold badges2323 silver badges4242 bronze badges answered May 8 '13 at 9:22 enyoenyo ...
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Could not locate Gemfile

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Remove duplicate elements from array in Ruby

... the Tin Man 147k3131 gold badges192192 silver badges272272 bronze badges answered Dec 3 '11 at 5:24 Mithun Sasidharan...