4 ! this was leading to an internal "mismatching comparison operand types"
7 ! Original testcase by minzastro <minzastro@googlemail.com>
8 ! Fixed by Dominique Dhumieres <dominiq@lps.ens.fr>
17 arr(1,:,:,:) = sum(arr, dim=1, mask=(arr(:,:,:,:) > 0d0))