program test
implicit none
REAL time_begin, time_end
integer, parameter :: n=2000;
REAL(8) :: a(n,n), b(n,n), c(n,n),as(n,n), bs(n,n)
integer, parameter :: m = 1
integer :: i, j, k, l
call RANDOM_NUMBER(as)
call RANDOM_NUMBER(bs)
c=0.d0
a=as
b=bs
call cpu_time(time_begin)
do i = 1,m
a(1,1) = a(1,1) + 0.1d0
c = MATMUL(a,b)
enddo
call cpu_time(time_end)
PRINT *, 'Time, MATMUL: ',time_end-time_begin, c(1,1)
c=0.d0
a=as
b=bs
call cpu_time(time_begin)
do i = 1,m
a(1,1) = a(1,1) + 0.1d0
c=0.d0
do j=1,n
do k=1,n
do l=1,n
c(l,k) =c(l,k)+ a(l,j)*b(j,k)
enddo
enddo
enddo
enddo
call cpu_time(time_end)
PRINT *, 'Time, MAT MUL custom: ',time_end-time_begin, c(1,1)
c=0.d0
a=as
b=bs
call cpu_time(time_begin)
do i = 1,m
a(1,1) = a(1,1) + 0.1d0
call dgemm('n','n',n, n, n, 1.0d0, a, n, b, n, 0.0d0, c, n)
enddo
call cpu_time(time_end)
PRINT *, 'dgemm: ',time_end-time_begin, c(1,1)
end program
|
