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How to map with index in Ruby?
...methods like map on. So you can do:
arr.each_with_index.map { |x,i| [x, i+2] }
In 1.8.6 you can do:
require 'enumerator'
arr.enum_for(:each_with_index).map { |x,i| [x, i+2] }
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What are the differences between numpy arrays and matrices? Which one should I use?
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answered Apr 11 at 11:52
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How can I access and process nested objects, arrays or JSON?
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26 Answers
26
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How to fix/convert space indentation in Sublime Text?
Example: If I have a document with 2 space indentation, and I want it to have 4 space indentation, how do I automatically convert it by using the Sublime Text editor?
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pandas GroupBy columns with NaN (missing) values
...e groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fillna(-1).groupby('b').sum()
Out[12]:
a
b
-1 2
4 1
6 3
That said, this feels pretty awful hack... perhaps there should be an option to include NaN in groupby (see this github issue ...
How to remove element from an array in JavaScript?
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12 Answers
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MySQL: What's the difference between float and double?
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edited Jan 29 '10 at 9:12
answered Jan 29 '10 at 9:04
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How to assign from a function which returns more than one value?
...ue then functionReturningTwoValues()[[1]] or functionReturningTwoValues()[[2]] would be sufficient.)
See the cited r-help thread for more examples.
(2) with If the intent is merely to combine the multiple values subsequently and the return values are named then a simple alternative is to use with...
Real life example, when to use OUTER / CROSS APPLY in SQL
...me,
pa.name
FROM sys.procedures pr
OUTER APPLY (SELECT TOP 2 *
FROM sys.parameters pa
WHERE pa.object_id = pr.object_id
ORDER BY pr.name) pa
ORDER BY pr.name,
pa.name
2) Calling a Table Valued Function for ...
How do I loop through a list by twos? [duplicate]
I want to loop through a Python list and process 2 list items at a time. Something like this in another language:
7 Answers...