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Transposing a NumPy array
...of a 1D array is still a 1D array! (If you're used to matlab, it fundamentally doesn't have a concept of a 1D array. Matlab's "1D" arrays are 2D.)
If you want to turn your 1D vector into a 2D array and then transpose it, just slice it with np.newaxis (or None, they're the same, newaxis is just mor...
How can I check for Python version in a program that uses new language features?
...rom the question that needed addressing is that a program must be syntactically correct for that version of python to even begin executing, so using new syntax precludes a program from starting on older versions of the interpreter. eval works around that
– Autoplectic
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How to enumerate an object's properties in Python?
...oes not return dynamic members (i.e., object attributes and methods dynamically defined by that object's __getattr__() method or similar magic). In all likelihood, your desired file.ImplementationName property is defined dynamically and hence not available to vars() or dir().
–...
Get name of object or class
...(function(){}); new myclass prints myclass {}
– Hugh Allen
May 26 '14 at 4:09
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jQuery get value of selected radio button
...use you when you're used to seeing "" as the default value via the .val() call.
– xji
Jan 8 '18 at 22:30
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Immutable vs Mutable types
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Almost, but not exactly. Technically, all variables are passed by reference in Python, but have a semantics more like pass by value in C. A counterexample to your analogy is if you do def f(my_list): my_list = [1, 2, 3]. With pass-by-reference in C, the val...
Getting visitors country from their IP
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why im getting unknow all the time with every ip ? , used same code.
– echo_Me
Feb 18 '14 at 18:12
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“Unknown provider: aProvider
...that caused this issue, but I have since been able to find the problem manually.
There was a controller function declared on the global scope, instead of using a .controller() call on the application module.
So there was something like this:
function SomeController( $scope, i18n ) { /* ... */ }
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Test if a variable is a list or tuple
... excludes custom sequences, iterators, and other things that you might actually need. However, sometimes you need to behave differently if someone, for instance, passes a string. My preference there would be to explicitly check for str or unicode like so:
import types
isinstance(var, types.String...
List of lists changes reflected across sublists unexpectedly
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When you write [x]*3 you get, essentially, the list [x, x, x]. That is, a list with 3 references to the same x. When you then modify this single x it is visible via all three references to it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 1405608979...
