This file documents the grid generator.

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FILE DESCRIPTION

  Generator files
    spgrid.c       grid graph generator
    Sspgrid.c      grid graph generator with an extra source
    
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PROGRAM PARAMETERS

  spgrid.exe, Sspgrid.exe
    take seven parameters, X, xL, xH, Y, yL, yH, S
      * X  is the grid length
      * xL is the lower bound on the horizontal arc length
      * xU is the upper bound on the horizontal arc length
      * Y  is the grid height
      * yL is the lower bound on the vertical arc length
      * yU is the upper bound on the vertical arc length
      * S  is the pseudorandom number generator seed

