2.21 Convert N by M matrix to a row of length N M

Given

a=[1 2 3 
   4 5 6 
   7 8 9]
 

covert the matrix to one vector

[1 2 3 4 5 6 7 8 9]
 

Mathematica a={{1,2,3}, {4,5,6}, {7,8,9}} Flatten[a]

{1,2,3,4,5,6,7,8,9}

 

Matlab a=[1 2 3; 4 5 6; 7 8 9] a=a(:); a'

1 4 7 2 5 8 3 6 9

 

Maple Maple reshapes along columns, like Matlab. To get same result as Mathematica, we can transpose the matrix first. To get same result as Matlab, do not transpose.

A:=Matrix([[1,2,3],[4,5,6],[7,8,9]]); v:=ListTools:-Flatten(convert(A,list)); v:=ListTools:-Flatten(convert(A^%T,list));

[1, 4, 7, 2, 5, 8, 3, 6, 9] [1, 2, 3, 4, 5, 6, 7, 8, 9]