Matrix multiplication: Difference between revisions

=={{header|SequenceL}}==

:The product of the ''m''×''p'' matrix ''A'' with the ''p''×''n'' matrix ''B'' is the ''m''×''n'' matrix whose (''i'',''j'')'th entry is

::<math>\sum_{k=1}^p A(i,k)B(k,j)</math>

The SequenceL definition mirrors that definition more or less exactly:

<lang sequencel>matmul(A(2), B(2)) [i,j] :=

let k := 1...size(B);

in sum( A[i,k] * B[k,j] );

//Example Use

a := [[1, 2],

[3, 4]];

b := [[-3, -8, 3],

[-2, 1, 4]];

test := matmul(a, b);</lang>

It can be written a little more simply using the all keyword:

<lang sequencel>matmul(A(2), B(2)) [i,j] := sum( A[i,all] * B[all,j] );</lang>