Hi,

I am using the intel fortran compiler for mac os x to calculate a computational fluid dynamic problems. Here is a very simple subroutine to generate the mesh.

subroutine make_grid() use global_parameters use flow_parameters use grid_arrays implicit none ! local variable integer :: i,j ! --- x direction --- if (xgrid_unif == 1) then dx1 = (xOut-xOrigin)/real(nx-1,KIND=CGREAL) do i=1,nx x(i) = xOrigin + real(i-1,KIND=CGREAL)*dx1 enddo else endif x(0) = xOrigin*2.0_CGREAL - x(2) x(nx+1) = x(nx)*2.0_CGREAL-x(nx-1) ! --- y direction --- if (ygrid_unif == 1) then dy1 = (yOut-yOrigin)/real(ny-1,KIND=CGREAL) do i=1,ny y(i) = yOrigin + real(i-1,KIND=CGREAL)*dy1 enddo else endif !debug do i=12,17 write(*,*) i,x(i) end do y(0) = yOrigin*2.0_CGREAL - y(2) y(nx+1) = y(ny)*2.0_CGREAL-y(ny-1) write(*,*) '-------------------------------------' !debug do i=12,17 write(*,*) i,x(i) end do stop do i=0,nx xc(i) = 0.5_CGREAL*(x(i+1)+x(i)) end do do i=0,ny yc(i) = 0.5_CGREAL*(y(i+1)+y(i)) end do ! --- write grid file for tecplot --- open(unit=14,file='grid_plot.plt') write(14,*)'variables="x","y"' write(14,*)'zone f=point, i=',nx+1,', j=',ny+1 do j=0,ny do i=0,nx write(14,'(2(2x,e14.7))') xc(i),yc(j) enddo enddo close(14) return end subroutine make_grid

In line 26 and 33, I output the value of the same variables twice. But the value of x(16) changes out of no reason, since the operation between these two outputs has nothing to do with x.

12 -0.225000000000000 13 -0.200000000000000 14 -0.175000000000000 15 -0.150000000000000 16 -0.125000000000000 17 -0.100000000000000 ------------------------------------- 12 -0.225000000000000 13 -0.200000000000000 14 -0.175000000000000 15 -0.150000000000000 16 0.525000000000000 17 -0.100000000000000

However, the same program works fine on ubuntu+intel fortran compiler.

Can someone help me with this?

I really appreciate your help.