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What are the differences between json and simplejson Python modules?
...
394
json is simplejson, added to the stdlib. But since json was added in 2.6, simplejson has the adv...
Index all *except* one item in python
... 3rd element:
a = range(10)[::-1] # [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
b = [x for i,x in enumerate(a) if i!=3] # [9, 8, 7, 5, 4, 3, 2, 1, 0]
This is very general, and can be used with all iterables, including numpy arrays. If you replace [] with (), b will be an iterator inst...
Find the max of two or more columns with pandas
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edited Dec 4 '16 at 19:06
alfredocambera
2,5382727 silver badges2626 bronze badges
answer...
Pass a data.frame column name to a function
...|
edited Apr 11 '16 at 21:42
joran
152k2525 gold badges379379 silver badges431431 bronze badges
answered...
Find XOR of all numbers in a given range
...given a large range [a,b] where 'a' and 'b' can be typically between 1 and 4,000,000,000 inclusive. You have to find out the XOR of all the numbers in the given range.
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Why does direction of index matter in MongoDB?
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114
MongoDB concatenates the compound key in some way and uses it as the key in a BTree.
When findi...
Get the cartesian product of a series of lists?
...hon 2.6.
import itertools
somelists = [
[1, 2, 3],
['a', 'b'],
[4, 5]
]
for element in itertools.product(*somelists):
print(element)
Which is the same as,
for element in itertools.product([1, 2, 3], ['a', 'b'], [4, 5]):
print(element)
...
Convert a row of a data frame to vector
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answered Jan 23 '13 at 16:42
Ben BolkerBen Bolker
160k1919 gold badges286286 silver badges366366 bronze badges
...
How to return a part of an array in Ruby?
...", "c" ]
a[1..3] #=> [ "b", "c", "d" ]
a[4..7] #=> [ "e" ]
a[6..10] #=> nil
a[-3, 3] #=> [ "c", "d", "e" ]
# special cases
a[5] #=> nil
a[6, 1] ...
Extract elements of list at odd positions
... second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2, 4, 6
Explanation
The [1::2] at the end is just a notation for list slicing. Usually it is in the following form:
some_list[start:stop:step]
If we omitted start, the default (0) would be used. So the first element (at po...