Matrix multiplication with a loop function

[h_c...@hotmail.co.uk]

Hello,

I am trying to write a code to multiply 2x2 matrices intrinsically with a loop function. I have managed to do this for an extrinsic example but this has required a fair few line of code and I would like to see if MiniZinc can do it in another way. The code I have written is as follows:

int: dim = 2;

array[1..dim,1..dim] of var float: A;

array[1..dim,1..dim] of var float: AA;

constraint A[1,1]=1.0;

constraint A[2,1]=2.0;

constraint A[1,2]=1.0;

constraint A[2,2]=3.0;

constraint forall (i in 1..dim, j in 1..dim) (

       sum (k in 1..dim) (A[i,k]*A[k,j]) = AA[i,j]

  );

solve satisfy;

output [show(A)];

Thank you,

Harry

[guido.tack]

You can use array comprehensions like this:

array[1..dim,1..dim] of float: A = [|1,2|1,3|];

array[int,int] of float: AA = array2d(1..dim,1..dim, [ sum (k in 1..dim) (A[i,k] * A[k,j]) | i,j in 1..dim ]);

Cheers,

Guido