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ArithmeticException: “Non-terminating decimal expansion; no exact representable decimal result”
...LF_UP
In this Case HALF_UP, will have this result:
2.4 = 2
2.5 = 3
2.7 = 3
You can check the RoundingMode information here: http://www.javabeat.net/precise-rounding-of-decimals-using-rounding-mode-enumeration/
shar...
How do I exchange keys with values in a dictionary?
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From Python 2.7 on, including 3.0+, there's an arguably shorter, more readable version:
>>> my_dict = {'x':1, 'y':2, 'z':3}
>>> {v: k for k, v in my_dict.items()}
{1: 'x', 2: 'y', 3: 'z'}
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Currency formatting in Python
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New in 2.7
>>> '{:20,.2f}'.format(18446744073709551616.0)
'18,446,744,073,709,551,616.00'
http://docs.python.org/dev/whatsnew/2.7.html#pep-0378
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Generate random numbers with a given (numerical) distribution
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Mark DickinsonMark Dickinson
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Printing Lists as Tabular Data
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Some ad-hoc code for Python 2.7:
row_format ="{:>15}" * (len(teams_list) + 1)
print(row_format.format("", *teams_list))
for team, row in zip(teams_list, data):
print(row_format.format(team, *row))
This relies on str.format() and the Format Spe...
Access an arbitrary element in a dictionary in Python
...u can use collections.OrderedDict, which is also in the forthcoming Python 2.7; for older versions of Python, download, install, and use the ordered dict backport (2.4 and later) which you can find here.
Python 3.7
Now dicts are insertion ordered.
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How to get the ASCII value of a character
...nstead of unichr.
ord() - Python 3.6.5rc1 documentation
ord() - Python 2.7.14 documentation
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Finding the mode of a list
...(1) # Returns the highest occurring item
Note: Counter is new in python 2.7 and is not available in earlier versions.
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Fastest way to iterate over all the chars in a String
...54.8 428.9 5.0 4.9 4.7 7.0 7.2
64 charAt 2.7 2.6 48.2 232.9 3.0 3.2 3.3 3.9 4.0
128 charAt 2.1 1.9 43.7 138.8 2.1 2.6 2.6 2.4 2.6
256 charAt 1.9 1.6 42.4 90.6 1.7 ...
Usage of __slots__?
...gs to __slots__.
To verify this, using the Anaconda distribution of Python 2.7 on Ubuntu Linux, with guppy.hpy (aka heapy) and sys.getsizeof, the size of a class instance without __slots__ declared, and nothing else, is 64 bytes. That does not include the __dict__. Thank you Python for lazy evaluati...