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How to merge lists into a list of tuples?
...
In Python 2:
>>> list_a = [1, 2, 3, 4]
>>> list_b = [5, 6, 7, 8]
>>> zip(list_a, list_b)
[(1, 5), (2, 6), (3, 7), (4, 8)]
In Python 3:
>>> list_a = [1, 2, 3, 4]
>>> list_b = [5, 6, 7, 8]
>>> list(zip(list_a, li...
How do I extract a sub-hash from a hash?
...azlerGazler
76k1515 gold badges250250 silver badges230230 bronze badges
2
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[] and {} vs list() and dict(), which is better?
...gt;> from timeit import timeit
>>> timeit("[]")
0.040084982867934334
>>> timeit("list()")
0.17704233359267718
>>> timeit("{}")
0.033620194745424214
>>> timeit("dict()")
0.1821558326547077
and for non-empty:
>>> timeit("[1,2,3]")
0.24316302770330367
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Select count(*) from multiple tables
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337
SELECT (
SELECT COUNT(*)
FROM tab1
) AS count1,
(
S...
Pandas - How to flatten a hierarchical index in columns
...|
edited Jan 17 '14 at 19:36
answered Jan 24 '13 at 18:37
A...
Multiple linear regression in Python
... my dependent variable (y) against several independent variables (x1, x2, x3, etc.).
13 Answers
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How many double numbers are there between 0.0 and 1.0?
...), there will therefore be 2 to the 52th power different doubles (i.e., 4503599627370496 of them). For example, that's the number of distinct doubles between 0.5 included and 1.0 excluded, and exactly that many also lie between 1.0 included and 2.0 excluded, and so forth.
Counting the doubles betw...
LINQ where vs takewhile
...d find all elements matching the condition
var intList = new int[] { 1, 2, 3, 4, 5, -1, -2 };
Console.WriteLine("Where");
foreach (var i in intList.Where(x => x <= 3))
Console.WriteLine(i);
Console.WriteLine("TakeWhile");
foreach (var i in intList.TakeWhile(x => x <= 3))
Console....
What is the difference between shallow copy, deepcopy and normal assignment operation?
...
367
Normal assignment operations will simply point the new variable towards the existing object. T...
Find nearest value in numpy array
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531
import numpy as np
def find_nearest(array, value):
array = np.asarray(array)
idx = (np....