Python
Python is a dynamic, strongly typed, object-oriented, multipurpose programming language, designed to be quick (to learn, to use, and to understand), and to enforce a clean and uniform syntax. Two similar but incompatible versions of Python are in use (Python 2.7 or 3.x). For version-specific Python questions, please also use the [python-2.7] or [python-3.x] tags. When using a Python variant (Jython, Pypy, Iron-python, etc.) - please also tag the variant.
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How to iterate over rows in a DataFrame in Pandas
I have a DataFrame from Pandas: import pandas as pd inp = [{'c1':10, 'c2':100}, {'c1
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"Least Astonishment" and the Mutable Default Argument
Anyone tinkering with Python long enough has been bitten (or torn to pieces) by the following issue: def foo(a
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How do I pass a variable by reference?
The Python documentation seems unclear about whether parameters are passed by reference or value, and the foll
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Convert bytes to a string
I'm using this code to get standard output from an external program: >>> from subprocess import
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How do I concatenate two lists in Python?
How do I concatenate two lists in Python? Example: listone = [1, 2, 3] listtwo = [4, 5, 6] Expected outcom
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How can I add new keys to a dictionary?
Is it possible to add a key to a Python dictionary after it has been created? It doesn't seem to have an
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What is the difference between __str__ and __repr__?
What is the difference between __str__ and __repr__ in Python?
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Catch multiple exceptions in one line (except block)
I know that I can do: try: # do something that may fail except: # do this if ANYTHING goes wrong I
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Using global variables in a function
How can I create or use a global variable in a function? If I create a global variable in one function, how c
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Iterating over dictionaries using 'for' loops
I am a bit puzzled by the following code: d = {'x': 1, 'y': 2, 'z': 3} for key
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Finding the index of an item in a list
Given a list ["foo", "bar", "baz"] and an item in the list "bar", how do I get its index (1) in Python?
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Understanding slice notation
I need a good explanation (references are a plus) on Python's slice notation. To me, this notation need
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Difference between staticmethod and classmethod
What is the difference between a function decorated with @staticmethod and one decorated with @classmethod?
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How to make a flat list out of a list of lists
Is there a shortcut to make a simple list out of a list of lists in Python? I can do it in a for loop, but is
