cl4_check - check topology of a map file (fortran)
Check the topology of a map file in RLInt CL4 format.
A map file in RLInt CL4 format is topologically valid if and only if:
To perform the third test, any causeways, if present, are removed by
decomposing the polygon into its subpolygons. Then we make sure that
(a) no segment in any subpolygon crosses a nonadjacent segment in the same
subpolygon (b) no segment in any subpolygon crosses any segment of any
other subpolygon from the same polygon.
- Only the first polygon (the external boundary) has negative area.
- The net area of the entire map is zero.
- No segment of any polygon intersects any other nonadjacent segment in
the same polygon.
EXECUTION: (on parep2.lbl.gov)
module load lang
f77 -g cl4_check.f -o cl4_check.exe