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Python nested functions variable scoping [duplicate]

...the statement b = 4 commented out, this code outputs 0 1, just what you'd expect. But if you uncomment that line, on the line print b, you get the error UnboundLocalError: local variable 'b' referenced before assignment It seems mysterious that the presence of b = 4 might somehow make b disappea...
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Is it possible to set code behind a resource dictionary in WPF for event handling?

Is it possible to set code behind a resource dictionary in WPF. For example in a usercontrol for a button you declare it in XAML. The event handling code for the button click is done in the code file behind the control. If I was to create a data template with a button how can I write the event handl...
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How to check if all list items have the same value and return it, or return an “otherValue” if they

... var val = yyy.First().Value; return yyy.All(x=>x.Value == val) ? val : otherValue; Cleanest way I can think of. You can make it a one-liner by inlining val, but First() would be evaluated n times, doubling execution time. To incorporate the "empty set" behavior ...
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ValueError: setting an array element with a sequence

... array from a list that isn't shaped like a multi-dimensional array. For example numpy.array([[1,2], [2, 3, 4]]) or numpy.array([[1,2], [2, [3, 4]]]) will yield this error message, because the shape of the input list isn't a (generalised) "box" that can be turned into a multidimensional array...
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rgdal package installation

The issue here is not exactly how to plot maps through R, as I have found already a pretty nice example here , but rather how to make it work. In fact, I am unable to load library rgdal : ...
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'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?

What explains the difference in behavior of boolean and bitwise operations on lists vs NumPy arrays? 8 Answers ...
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How to take all but the last element in a sequence using LINQ?

...e; T item = default(T); do { hasRemainingItems = it.MoveNext(); if (hasRemainingItems) { if (!isFirst) yield return item; item = it.Current; isFirst = false; } } while (hasRemainingItems); } static void Main(string[] args) { ...
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Logical XOR operator in C++?

...sarily do what you might want for non-booleans. And as this is C++, there exists a real bool type instead of having to use int for that purpose. – Greg Hewgill Oct 20 '09 at 21:19 ...
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Is there an easy way to pickle a python function (or otherwise serialize its code)?

...hich can then be reassembled into a function. ie: import marshal def foo(x): return x*x code_string = marshal.dumps(foo.func_code) Then in the remote process (after transferring code_string): import marshal, types code = marshal.loads(code_string) func = types.FunctionType(code, globals(), "so...
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What is tail recursion?

...learn lisp, I've come across the term tail-recursive . What does it mean exactly? 28 Answers ...