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How do you round a floating point number in Perl?

... can have serious implications, and the rounding method used should be specified precisely. In these cases, it probably pays not to trust whichever system rounding is being used by Perl, but to instead implement the rounding function you need yourself. To see why, notice how you'll still have an i...
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Getting the docstring from a function

....getdoc. It cleans up the __doc__ by normalizing tabs to spaces and left shifting the doc body to remove common leading spaces. share | improve this answer | follow ...
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How do I check if there are duplicates in a flat list?

... Use set() to remove duplicates if all values are hashable: >>> your_list = ['one', 'two', 'one'] >>> len(your_list) != len(set(your_list)) True share |...
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Sending a message to nil in Objective-C

...ize(); ++i){ System.out.println(list.get(i).toString()); } } Now, if you call that method like so: someObject.foo(NULL); you're going to probably get a NullPointerException when it tries to access list, in this case in the call to list.size(); Now, you'd probably never call someObject....
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How to output a multiline string in Bash?

... Not great if you need this in a function because you'll either need to 1) outdent the string all the way to the left of your file or 2) keep it indented to line up with the rest of your code but then it prints with the indents as well ...
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How to get a cross-origin resource sharing (CORS) post request working

...llow the response to continue. You need to ensure the response header specifically includes the required headers. ie: Access-Control-Allow-Headers: x-requested-with share | improve this answer...
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Python None comparison: should I use “is” or ==?

... when you want to check against an object's identity (e.g. checking to see if var is None). Use == when you want to check equality (e.g. Is var equal to 3?). Explanation: You can have custom classes where my_var == None will return True e.g: class Negator(object): def __eq__(self,other): ...
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How to dynamically compose an OR query filter in Django?

... How can you compose raw queries with Django if you want to add optional conditions like above? – user Jul 13 '14 at 18:34 ...
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matplotlib does not show my drawings although I call pyplot.show()

... This answer is old, config should now be in ~/.config/matplotlib/matplotlibrc (for python 3, at least). I just had a related problem, and I think it was caused by using matplotlib in python 2.7, which created a ~/.matplotlib/ directory, and stopped python 3 f...
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✔ Checkmark selected row in UITableViewCell

... What if I want only the checkmark and want to deselect the row after a selection? – gyozo kudor Jan 8 '15 at 8:59 ...