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How to count the number of true elements in a NumPy bool array

...e following. numpy.sum(boolarr) numpy.count_nonzero(boolarr) Here's an example: >>> import numpy as np >>> boolarr = np.array([[0, 0, 1], [1, 0, 1], [1, 0, 1]], dtype=np.bool) >>> boolarr array([[False, False, True], [ True, False, True], [ True, False,...
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How do I validate a date string format in python?

... >>> import datetime >>> def validate(date_text): try: datetime.datetime.strptime(date_text, '%Y-%m-%d') except ValueError: raise ValueError("Incorrect data format, should be YYYY-MM-DD") >>> validate('2003-12-23') >>> vali...
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Automatic Preferred Max Layout Width is not available on iOS versions prior to 8.0

I opened an existing iOS project with Xcode6 beta6, and Xcode lists the following warning for both Storyboard and Xib files: ...
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bash assign default value

...G_VARIABLE_NAME=${LONG_VARIABLE_NAME:-hello} , but now bash also tries to execute 'hello' and that gives a command not found. Any way to avoid that? Or will I have to stick to the latter? Can someone give an example where the assign default is actually useful? ...
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How to start nginx via different port(other than 80)

Hi I am a newbie on nginx, I tried to set it up on my server(running Ubuntu 4), which already has apache running. 5 Answer...
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Maven: missing net.sf.json-lib

... Failed to resolve dependency.. Any idea why ? – Alexandre Bourlier May 30 '12 at 16:48 2 Right....
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How to find current transaction level?

...' WHEN 5 THEN 'Snapshot' END AS TRANSACTION_ISOLATION_LEVEL FROM sys.dm_exec_sessions where session_id = @@SPID docs.microsoft.com reference for the constant values. share | improve this answer...
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Preserve colouring after piping grep to grep

... grep sometimes disables the color output, for example when writing to a pipe. You can override this behavior with grep --color=always The correct command line would be grep --color=always WORD * | grep -v AVOID This is pretty verbose, alternatively you can just add ...
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Given an RGB value, how do I create a tint (or shade)?

...r lighter (tinted) color: RGB: To shade: newR = currentR * (1 - shade_factor) newG = currentG * (1 - shade_factor) newB = currentB * (1 - shade_factor) To tint: newR = currentR + (255 - currentR) * tint_factor newG = currentG + (255 - currentG) * tint_factor newB = currentB + (255 - currentB...
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Why do results vary based on curly brace placement?

...ld be the end of a statement, are automatically terminated, so your first example looks effectively like this: function test() { return; // <- notice the inserted semicolon { javascript: "fantastic" }; } See also Douglas Crockford's JS style guide, which mentions semicolon insertio...