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Best way to find if an item is in a JavaScript array? [duplicate]
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As of ECMAScript 2016 you can use includes()
arr.includes(obj);
If you want to support IE or other older browsers:
function include(arr,obj) {
return (arr.indexOf(obj) != -1);
}
EDIT:
This will not work on IE6, 7 or 8 though. The bes...
How to create NS_OPTIONS-style bitmask enumerations in Swift?
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Can hash tables really be O(1)?
It seems to be common knowledge that hash tables can achieve O(1), but that has never made sense to me. Can someone please explain it? Here are two situations that come to mind:
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Finding ALL duplicate rows, including “elements with smaller subscripts”
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130
duplicated has a fromLast argument. The "Example" section of ?duplicated shows you how to use...
'Must Override a Superclass Method' Errors after importing a project into Eclipse
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How to extract the decision rules from scikit-learn decision-tree?
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21 Answers
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Replacement for “rename” in dplyr
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148
dplyr version 0.3 added a new rename() function that works just like plyr::rename().
df <-...
Changing the “tick frequency” on x or y axis in matplotlib?
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11 Answers
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