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Pandas DataFrame Groupby two columns and get counts

...).reset_index().groupby('col2')[[0]].max() Out[56]: 0 col2 A 3 B 2 C 1 D 3 share | improve this answer | follow | ...
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typeof for RegExp

... | edited Nov 27 '18 at 6:34 Alexis Wilke 14.2k77 gold badges5151 silver badges9898 bronze badges answer...
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How to split a sequence into two pieces by predicate?

... By using partition method: scala> List(1,2,3,4).partition(x => x % 2 == 0) res0: (List[Int], List[Int]) = (List(2, 4),List(1, 3)) share | improve this answer ...
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Convert bytes to a string

... 3949 You need to decode the bytes object to produce a string: >>> b"abcde" b'abcde' # u...
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Difference between & and && in Java? [duplicate]

... 389 & is bitwise. && is logical. & evaluates both sides of the operation. &&a...
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String formatting named parameters?

... In Python 2.6+ and Python 3, you might choose to use the newer string formatting method. print('<a href="{0}">{0}</a>'.format(my_url)) which saves you from repeating the argument, or print('<a href="{url}">{url}</a>'.format...
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How to initialize all members of an array to the same value in Swift?

...ue like this: With old Swift version: var threeDoubles = [Double](count: 3, repeatedValue: 0.0) Since Swift 3.0: var threeDoubles = [Double](repeating: 0.0, count: 3) which would give: [0.0, 0.0, 0.0] share ...
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MAMP Pro 3.05 on Mavericks updated to Yosemite - Apache does not start

I have been running MAMP Pro 3.05 successfully in Yosemite up to DP4 on a partition that was a clean install of Yosemite. 1...
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How to implement a queue with three stacks?

...SUMMARY O(1) algorithm is known for 6 stacks O(1) algorithm is known for 3 stacks, but using lazy evaluation which in practice corresponds to having extra internal data structures, so it does not constitute a solution People near Sedgewick have confirmed they are not aware of a 3-stack solution wi...
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Rails - controller action name to string

... 339 Rails 2.X: @controller.action_name Rails 3.1.X: controller.action_name, action_name Rails 4....