Array#transpose
Array#transposeは、二次元配列を行列に見立てて 転置行列を得ます。
require 'pp' a = [ [ 11, 12, 13 ], [ 21, 22, 23 ], [ 31, 32, 33 ], [ 41, 42, 43 ], ] PP.pp(a, STDOUT, 20) PP.pp(a.transpose, STDOUT, 20)
実行結果です。
[[11, 12, 13], [21, 22, 23], [31, 32, 33], [41, 42, 43]] [[11, 21, 31, 41], [12, 22, 32, 42], [13, 23, 33, 43]]