- #1

autobot.d

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So I have a program that calls a module that contains a subroutine so I can make a matrix.

When I write the matrix in the subroutine (commented out part in module) I get the right output, but when the main program tries to output it is some insanely small or large numbers.

I am new to Fortran (not coding) so any help/criticism would be greatly appreciated! Definitely a bit of a learning curve but I am excited to learn fortran.

Code:

```
program test
use test_mod
implicit none
integer :: k
real, allocatable, Dimension(:,:) :: test_mat
write(*,*) 'Dimension for square test matrix: '
read (*,*) k
allocate(test_mat(k,k))
call test_matrix(k)
!This gives bad output, but right dimensions
write(*,*) test_mat
deallocate(test_mat)
end program test
```

Code:

```
module test_mod
implicit none
contains
subroutine test_matrix(k)
integer :: k
real, dimension(:,:), allocatable :: test_mat
INTEGER :: i,j,m,n
allocate(test_mat(k,k))
do i = 1,k
do j = 1,k
test_mat(i,j) = 1.d0*((i+j-1))
end do
end do
!This loop gives correct output
!do m = 1,k
!write(*,*)(test_mat(m,n), n=1,k)
!end do
deallocate(test_mat)
end subroutine test_matrix
end module test_mod
```