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Are list-comprehensions and functional functions faster than “for loops”?
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154
The following are rough guidelines and educated guesses based on experience. You should timeit ...
SQL Logic Operator Precedence: And and Or
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ludovico
78044 silver badges1515 bronze badges
answered Aug 6 '09 at 20:19
Charles BretanaCharles Bretana
1...
How do you detect Credit card type based on number?
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+50
The credit/debit card number is referred to as a PAN, or Primary Account Number. The first six digits of the PAN are taken from the ...
Convert pandas dataframe to NumPy array
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15 Answers
15
Active
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What is the difference between 0.0.0.0, 127.0.0.1 and localhost?
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425
127.0.0.1 is normally the IP address assigned to the "loopback" or local-only interface. This i...
Get operating system info
...s that, it sniffs your core operating system model, for example windows nt 5.1 as my own.
It then passes windows nt 5.1/i to Windows XP as the operating system.
Using: '/windows nt 5.1/i' => 'Windows XP', from an array.
You could say guesswork, or an approximation yet nonetheless pretty much ...
No provider for “framework:jasmine”! (Resolving: framework:jasmine)
..."~0.7.0",
"grunt-concurrent": "~0.4.1",
"grunt-contrib-clean": "~0.5.0",
"grunt-contrib-coffee": "~0.7.0",
"grunt-contrib-compass": "~0.6.0",
"grunt-contrib-concat": "~0.3.0",
"grunt-contrib-connect": "~0.5.0",
"grunt-contrib-copy": "~0.4.1",
"grunt-contrib-cssmin": "...
how do I insert a column at a specific column index in pandas?
...insert(loc, column, value)
df = pd.DataFrame({'B': [1, 2, 3], 'C': [4, 5, 6]})
df
Out:
B C
0 1 4
1 2 5
2 3 6
idx = 0
new_col = [7, 8, 9] # can be a list, a Series, an array or a scalar
df.insert(loc=idx, column='A', value=new_col)
df
Out:
A B C
0 7 1 4
1 8 2 5
2 9 ...
Using numpy to build an array of all combinations of two arrays
...lementation:
@pv's solution
In [113]:
%timeit cartesian(([1, 2, 3], [4, 5], [6, 7]))
10000 loops, best of 3: 135 µs per loop
In [114]:
cartesian(([1, 2, 3], [4, 5], [6, 7]))
Out[114]:
array([[1, 4, 6],
[1, 4, 7],
[1, 5, 6],
[1, 5, 7],
[2, 4, 6],
[2, 4, 7],
...