intrinsic_product.f90   [plain text]

! Program to test the PRODUCT intrinsic
program testproduct
   implicit none
   integer, dimension (3, 3) :: a
   integer, dimension (3) :: b
   logical, dimension (3, 3) :: m

   a = reshape ((/1, 2, 3, 4, 5, 6, 7, 8, 9/), (/3, 3/));

   b = product (a, 1)

   if (any(b .ne. (/6, 120, 504/))) call abort

   if (product (a) .ne. 362880) call abort

   m = .true.
   m(1, 1) = .false.
   m(2, 1) = .false.
   b = product (a, 2, m)

   if (any(b .ne. (/28, 40, 162/))) call abort

   if (product (a, mask=m) .ne. 181440) call abort

end program