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Calling a function of a module by using its name (a string)
What is the best way to go about calling a function given a string with the function's name in a Python program. For example, let's say that I have a module foo , and I have a string whose content is "bar" . What is the best way to call foo.bar() ?
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Which characters make a URL invalid?
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@techiferous, Yeah, I forgot to allow "%" escaped characters. It should've looked more like: /^([!#$&-;=?-[]_a-z~]|%[0-9a-fA-F]{2})+$/ Was there anything else that you found it should've been accepting? (Just to be clear, that regex only checks ...
How can I count the occurrences of a list item?
...1, 4, 1].count(1)
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Don't use this if you want to count multiple items. Calling count in a loop requires a separate pass over the list for every count call, which can be catastrophic for performance. If you want to count all items, or even just multiple items, use Counter, as explained in the othe...
Drop all tables whose names begin with a certain string
How can I drop all tables whose names begin with a given string?
14 Answers
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When to use ' (or quote) in Lisp?
...al operator (quote) (or equivalent ' ) function does, yet this has been all over Lisp code that I've seen.
10 Answers
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How to create a video from images with FFmpeg?
...pix_fmt yuv420p out.ogg
Your images should of course be sorted alphabetically, typically as:
0001-first-thing.jpg
0002-second-thing.jpg
0003-and-third.jpg
and so on.
I would also first ensure that all images to be used have the same aspect ratio, possibly by cropping them with imagemagick or n...
How to get the input from the Tkinter Text Widget?
...he end of the text box is reached. The only issue with this is that it actually adds a newline to our input. So, in order to fix it we should change END to end-1c(Thanks Bryan Oakley) The -1c deletes 1 character, while -2c would mean delete two characters, and so on.
def retrieve_input():
input...
Regex, every non-alphanumeric character except white space or colon
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[^a-zA-Z\d\s:]
\d - numeric class
\s - whitespace
a-zA-Z - matches all the letters
^ - negates them all - so you get - non numeric chars, non spaces and non colons
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How to work with complex numbers in C?
...h:
creal(z1): get the real part (for float crealf(z1), for long double creall(z1))
cimag(z1): get the imaginary part (for float cimagf(z1), for long double cimagl(z1))
Another important point to remember when working with complex numbers is that functions like cos(), exp() and sqrt() must be repl...
How to reference a file for variables using Bash?
I want to call a settings file for a variable, how can I do this in bash?
9 Answers
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