Added support for OpenMP. Cleaned up makefile. Added gnuplot file for `make plots`.

1 files changed, 18 insertions, 9 deletions

diff --git a/matrixproduct.f90 b/matrixproduct.f90
index e622ac2..d7b3d13 100644
--- a/matrixproduct.f90
+++ b/matrixproduct.f90
@@ -6,7 +6,7 @@ program matrixproduct
     !>  2. Fortran native matmul routine
     !>  3. LAPACK/BLAS library call
         
-    use :: omp_lib
+    use omp_lib
     use, intrinsic :: iso_fortran_env
     implicit none
     external :: dgemm   !> double-precision general matrix-matrix multiplication
@@ -16,24 +16,31 @@ program matrixproduct
     integer(int32) :: n, start_num, step_num, stop_num
     character(10) :: temp_in
     logical :: run_loops
+    
+    !> Start by taking the command-line arguments. This is useful because
+    !> it lets us call the program from Bash with a variable matrix size
 
     call get_command_argument(1, temp_in)
     read(temp_in,'(i10)') start_num
     call get_command_argument(2, temp_in)
-    read(temp_in,'(i10)') step_num
-    call get_command_argument(3, temp_in)
     read(temp_in,'(i10)') stop_num
+    call get_command_argument(3, temp_in)
+    read(temp_in,'(i10)') step_num
+    !> The last argument is a string [yes/no] that instructs the program
+    !> to either run with the triple-loops or ignore them completely.
     call get_command_argument(4, temp_in)
-    select case (temp_in)
-        case ('yes       ')
+    select case (trim(temp_in))
+        case ('yes')
             run_loops=.TRUE.
-        case ('no        ')
+        case ('no')
             run_loops=.FALSE.
         case default
-            write(*,'(A,A,A)') "WARNING: ",temp_in," not supported argument for run_loops [yes/no]"
+            write(*,'("WARNING:",A," is not a supported argument [yes/no], defaulting to YES")') temp_in
+            run_loops=.TRUE.
     end select 
 
-    write(*,'(A,i10,i10,i10)') "Running with start, step, stop ",start_num,step_num,stop_num
+    write(*,'("Compiled with ",A,A," on ",A)') COMPILER_VERSION(), COMPILER_OPTIONS()
+    write(*,'("Running with start=",I0,", stop=",I0,", step=",I0)') start_num, stop_num, step_num
     
     do n = start_num, stop_num, step_num
         call prep_mats(A,B,C,n)
@@ -94,7 +101,7 @@ contains
         integer(int32), intent(in) :: n
         integer(int32) :: i, j, k
 
-        !$omp parallel do private(i,j,k)
+        !$omp parallel do private(j,k)
         row: do i = 1,n
             col: do j = 1,n
                 sum: do k = 1,n
@@ -112,6 +119,7 @@ contains
         integer(int32), intent(in) :: n
         integer(int32) :: i, j, k
 
+        !$omp parallel do private(j,k)
         col: do j = 1,n
             row: do i = 1,n
                 sum: do k = 1,n
@@ -119,6 +127,7 @@ contains
                 end do sum
             end do row
         end do col 
+        !$omp end parallel do
 
     end subroutine triple_loop_mul_alt