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Check if an element is present in an array [duplicate]
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ECMAScript 2016 incorporates an includes() method for arrays that specifically solves the problem, and so is now the preferred method.
[1, 2, 3].includes(2); // true
[1, 2, 3].includes(4); // false
[1, 2, 3].includes(1, 2); //...
How to sum a variable by group
...quency, by=list(Category=x$Category), FUN=sum)
Category x
1 First 30
2 Second 5
3 Third 34
In the example above, multiple dimensions can be specified in the list. Multiple aggregated metrics of the same data type can be incorporated via cbind:
aggregate(cbind(x$Frequency, x$Metric2,...
python dataframe pandas drop column using int
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You can delete column on i index like this:
df.drop(df.columns[i], axis=1)
It could work stra...
Difference between declaring variables before or in loop?
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How to downgrade or install an older version of Cocoapods
... of cocoa pods via the following command:
sudo gem install cocoapods -v 0.25.0
You can use older installed versions with following command:
pod _0.25.0_ setup
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int a[] = {1,2,}; Weird comma allowed. Any particular reason?
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Hidden Features of JavaScript? [closed]
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Calculate the median of a billion numbers
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C# Sortable collection which allows duplicate keys
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answered Feb 19 '14 at 16:23
KnasterbaxKnasterbax
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