blob: 568a76d637a14ea5cc1da6de76cc9976dc0d7b7f (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
|
{ ... }:
{
/* For a list of length n that consists of lists of length m,
return a list of length m containing lists of length n
so that
builtins.elemAt (builtins.elemAt orig a) b
== builtins.elemAt (builtins.elemAt transposed b) a
Essentially, if you think of the nested list as an array with two
dimensions, the two index axes are swapped.
The length of the inner lists m is determined based on the first element
and assumed to be used for all other lists. Malformed input data may
cause the function to crash or lose data.
Type: <n>[ <m>[ ] ] -> <m>[ <n>[ ] ]
*/
transpose = list:
let
innerLength = builtins.length (builtins.head list);
outerLength = builtins.length list;
in
builtins.genList
(inner: builtins.genList
(outer: builtins.elemAt (builtins.elemAt list outer) inner)
outerLength)
innerLength;
}
|