Name: Anonymous 2008-02-27 15:53
$ cat f1.f
PROGRAM f
implicit none
integer H, I, J
integer A(1024, 1024)
do 10 H = 0, 30
do 20 I = 1, 1024
do 30 J = 1, 1024
A(I,J) = 0
30 continue
20 continue
10 continue
end program f
$ time ./f1
real 0m3.086s
user 0m3.063s
sys 0m0.019s
$ cat f2.c
int main(void)
{
int h, i, j, a[1024][1024];
for (h = 0; h < 10; h++)
for (i = 0; i < 1024; i++)
for (j = 0; j < 1024; j++)
a[i][j] = 0; // !!
return 0;
}
$ time ./f2
real 0m0.080s
user 0m0.072s
sys 0m0.008sWhy is the FORTRAN version almost as slow as Ruby, which is slow as fuck?