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Is it possible to use 'else' in a list comprehension? [duplicate]
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Note that this only works in Python 2.5 and later.
– Kevin Horn
Jun 1 '10 at 22:20
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Mean per group in a data.frame [duplicate]
I have a data.frame and I need to calculate the mean per group (i.e. per Month , below).
8 Answers
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python dataframe pandas drop column using int
I understand that to drop a column you use df.drop('column name', axis=1). Is there a way to drop a column using a numerical index instead of the column name?
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How should I validate an e-mail address?
...chnique for validating an e-mail address (e.g. from a user input field) in Android? org.apache.commons.validator.routines.EmailValidator doesn't seem to be available. Are there any other libraries doing this which are included in Android already or would I have to use RegExp?
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How to use/install gcc on Mac OS X 10.8 / Xcode 4.4
I have install Mountain Lion (Mac OS X 10.8) and now gcc doesn't seem to be available anymore. I've also installed Xcode 4.4 so there is no more /Developer directory.
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join list of lists in python [duplicate]
...t sends the elements of a as arguments to chain, like removing the outer [ and ]).
– Evgeni Sergeev
Jan 9 '14 at 6:00
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Reverse Range in Swift
...here for the bounds.
Earlier edit for Swift 1.2: As of Xcode 6 Beta 4, by and ReverseRange don't exist anymore :[
If you are just looking to reverse a range, the reverse function is all you need:
for i in reverse(1...5) { println(i) } // prints 5,4,3,2,1
As posted by 0x7fffffff there is a new s...
Installing Java on OS X 10.9 (Mavericks)
....8 (Mountain Lion). When I upgraded it to Mac OS X v10.9 (Mavericks) and ran java -version in the terminal, it showed:
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Math - mapping numbers
How do I map numbers, linearly, between a and b to go between c and d.
9 Answers
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How to check if all list items have the same value and return it, or return an “otherValue” if they
..., otherwise I need to use an “otherValue”. I can’t think of a simple and clear way of doing this.
9 Answers
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