MATLAB Convert MatLab to F90: Meshgrid [x,y]

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The discussion focuses on converting a MATLAB line of code that generates a mesh grid into Fortran 90. The original MATLAB command creates a grid of x and y values based on specified increments. The Fortran 90 code provided initializes arrays for x and y, allocates them based on the specified increments, and uses nested loops to populate the arrays with calculated values. A key point raised is the assumption that the starting point is always zero, which simplifies the allocation process. An alternative method is suggested using the SPREAD function to create the x and y arrays more concisely without nested loops. This approach emphasizes efficiency and clarity in the code while still achieving the desired output.
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What is the shortest way to convert this MatLab line

[x,y] = meshgrid(0:hx:xm, 0:hy:ym);

to F90?
Thanks in advance =)
 
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Code:
PROGRAM create_arrays

IMPLICIT NONE

INTEGER :: i,j,hx,hy,mx,my
REAL :: xcount,ycount,xint,yint
REAL,DIMENSION(:,:),ALLOCATBLE :: x,y

xcount = 0.0
ycount = 0.0
xint = REAL( (mx-1)/hx )
yint = REAL( (my-1)/hy )
ALLOCATE( x(mx/hx),&
          y(mx/hx) )

DO i=0,xm,hx
 DO j=0,ym,hy
   x(i,j) = xcount
   y(i,j) = ycount
   ycount = ycount + yint
  END DO
  ycount = 0.0
  xcount = xcount + xint
END DO

DEALLOCATE( x,y )

END PROGRAM

Note that for laziness I'm assuming that you'll ALWAYS be starting from zero. Also, the allocate will only work if the maximum divided by the "stride" is an integer.

Rather than specify it like MATLAB does with the meshgrid command (I had to look it up), I would specify and a range and a number of points. That way the allocate is easy (allocate to number of points), and the interval is simply the range divided by the number of points.

Either way, it'll get you close. You'll need to put the actual variables in there somehow, by either direct specification or by read/write commands; up to you.
 
Thank you, minger, but I think i found a shorter way: instead of the do cycle

x = SPREAD((/(hx*j, j = 0,Nx)/), 1, Nx+1)
y = SPREAD((/(hy*j, j = 0,Ny)/), 2, Ny+1)
 
Very nice!
 

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