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Python: split a list based on a condition?
What's the best way, both aesthetically and from a performance perspective, to split a list of items into multiple lists based on a conditional? The equivalent of:
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Test if a vector contains a given element
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Both the match() (returns the first appearance) and %in% (returns a Boolean) functions are designed for this.
v <- c('a','b','c','e')
'b' %in% v
## returns TRUE
match('b',v)
## returns the first location of 'b', in this case: 2
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Remove rows with all or some NAs (missing values) in data.frame
... 1 2 3 2
but using complete.cases is quite a lot more clear, and faster.
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What's the difference between belongs_to and has_one?
What is the difference between a belongs_to and a has_one ?
5 Answers
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How to mock localStorage in JavaScript unit tests?
...foreEach(function () {
var store = {};
spyOn(localStorage, 'getItem').andCallFake(function (key) {
return store[key];
});
spyOn(localStorage, 'setItem').andCallFake(function (key, value) {
return store[key] = value + '';
});
spyOn(localStorage, 'clear').andCallFake(function () {...
How to choose an AES encryption mode (CBC ECB CTR OCB CFB)?
...used if encrypting more than one block of data with the same key.
CBC, OFB and CFB are similar, however OFB/CFB is better because you only need encryption and not decryption, which can save code space.
CTR is used if you want good parallelization (ie. speed), instead of CBC/OFB/CFB.
XTS mode is the ...
Changing the image source using jQuery
...id the trick. .destroy() doesn't go nearly far enough. Nuking all the html and than init again actually works when swapping out images of various sizes and such.
– Matt J.
Apr 11 '14 at 16:36
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form serialize javascript (no framework)
...cript without jquery or any framework that allows me to serialize the form and access the serialized version?
22 Answers
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In Python, how do you convert a `datetime` object to seconds?
...ies for the simple question... I'm new to Python... I have searched around and nothing seems to be working.
10 Answers
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RegEx to find two or more consecutive chars
...{2} without the comma should also work, right?
– Alexander Mills
Sep 6 '18 at 21:09
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Alexander,...