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Is there a difference between using a dict literal and a dict constructor?
...d BUILD_MAP and STORE_MAP opcodes rather than generic CALL_FUNCTION:
> python2.7 -m timeit "d = dict(a=1, b=2, c=3, d=4, e=5)"
1000000 loops, best of 3: 0.958 usec per loop
> python2.7 -m timeit "d = {'a':1, 'b':2, 'c':3, 'd':4, 'e':5}"
1000000 loops, best of 3: 0.479 usec per loop
> pyt...
Getting the exception value in Python
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For python2, It's better to use e.message to get the exception message, this will avoid possible UnicodeDecodeError. But yes e.message will be empty for some kind of exceptions like OSError, in which case we can add a exc_info=Tr...
Very large matrices using Python and NumPy
...oing SQL-like GROUP BY aggregation at 1,000,000 rows/second. Not bad for a Python-based solution!
Accessing the data as a NumPy recarray again is as simple as:
data = table[row_from:row_to]
The HDF library takes care of reading in the relevant chunks of data and converting to NumPy.
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Python string prints as [u'String']
...d as Unicode to bytes in most cases: you should print Unicode directly in Python: print(', '.join([u'ABC' , u'...']))
– jfs
Jun 12 '16 at 17:20
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Python to print out status bar and percentage
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There's a Python module that you can get from PyPI called progressbar that implements such functionality. If you don't mind adding a dependency, it's a good solution. Otherwise, go with one of the other answers.
A simple example of ho...
Get Element value with minidom with Python
I am creating a GUI frontend for the Eve Online API in Python.
9 Answers
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Using python “with” statement with try-except block
Is this the right way to use the python "with" statement in combination with a try-except block?:
4 Answers
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How can I list the contents of a directory in Python?
...e I originally answered this question years ago, pathlib has been added to Python. My preferred way to list a directory now usually involves the iterdir method on Path objects:
from pathlib import Path
print(*Path("/home/username/www/").iterdir(), sep="\n")
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How to document a method with parameter(s)?
How to document methods with parameters using Python's documentation strings?
8 Answers
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Python: how to print range a-z?
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I believe string.ascii_lowercase already worked in python 2.x, so to be sure just always use ascii_lowercase.
– johk95
Aug 23 '17 at 11:32
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