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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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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 ...
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 to remove element from an array in JavaScript?
...
12 Answers
12
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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...
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...
Why use the params keyword?
...
With params you can call your method like this:
addTwoEach(1, 2, 3, 4, 5);
Without params, you can’t.
Additionally, you can call the method with an array as a parameter in both cases:
addTwoEach(new int[] { 1, 2, 3, 4, 5 });
That is, params allows you to use a shortcut when call...
Why can't R's ifelse statements return vectors?
...st vectors, you will get longer results:
> ifelse(c(TRUE, FALSE), c(1, 2), c(3, 4))
[1] 1 4
So ifelse is intended for the specific purpose of testing a vector of booleans and returning a vector of the same length, filled with elements taken from the (vector) yes and no arguments.
It is a comm...