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JavaScript variable assignments from tuples
In other languages like Python 2 and Python 3, you can define and assign values to a tuple variable, and retrieve their values like this:
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python max function using 'key' and lambda expression
I come from OOP background and trying to learn python.
I am using the max function which uses a lambda expression to return the instance of type Player having maximum totalScore among the list players .
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open() in Python does not create a file if it doesn't exist
...the file does not exist, it creates a new file for
reading and writing. -Python file modes
seek() method sets the file's current position.
f.seek(pos [, (0|1|2)])
pos .. position of the r/w pointer
[] .. optionally
() .. one of ->
0 .. absolute position
1 .. relative position to current
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How to un-escape a backslash-escaped string?
...s a backslash-escaped version of another string. Is there an easy way, in Python, to unescape the string? I could, for example, do:
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How to set up a PostgreSQL database in Django
I'm new to Python and Django.
11 Answers
11
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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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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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