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Is there any pythonic way to combine two dicts (adding values for keys that appear in both)?
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842
Use collections.Counter:
>>> from collections import Counter
>>> A = Counter...
How do I achieve the theoretical maximum of 4 FLOPs per cycle?
How can the theoretical peak performance of 4 floating point operations (double precision) per cycle be achieved on a modern x86-64 Intel CPU?
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Understanding the map function
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451
map isn't particularly pythonic. I would recommend using list comprehensions instead:
map(f, ...
What is the difference between shallow copy, deepcopy and normal assignment operation?
...inal.
Here's a little demonstration:
import copy
a = [1, 2, 3]
b = [4, 5, 6]
c = [a, b]
Using normal assignment operatings to copy:
d = c
print id(c) == id(d) # True - d is the same object as c
print id(c[0]) == id(d[0]) # True - d[0] is the same object as c[0]
Using a shall...
Converting string to numeric [duplicate]
...pect you are having a problem with factors. For example,
> x = factor(4:8)
> x
[1] 4 5 6 7 8
Levels: 4 5 6 7 8
> as.numeric(x)
[1] 1 2 3 4 5
> as.numeric(as.character(x))
[1] 4 5 6 7 8
Some comments:
You mention that your vector contains the characters "Down" and "NoData". What do ...
git + LaTeX workflow
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abcdabcd
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How do I find the stack trace in Visual Studio?
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edited Dec 17 '15 at 22:40
Jim Aho
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answered Ju...
Asp.net 4.0 has not been registered
...tudio Tools, namely: Visual Studio Command Prompt (2010) Visual Studio x64 Cross Tools Command Prompt (2010) Visual Studio x64 Win64 Command Prompt (2010) Does it matter which one is used for this command?
– B. Clay Shannon
Apr 25 '13 at 17:01
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How do I get the opposite (negation) of a Boolean in Python?
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174
You can just use:
return not bool
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How do I do an OR filter in a Django query?
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Alex KoshelevAlex Koshelev
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