... can be used as guide line for solving contour.
Will leave it as is, unless some question arise.
Smath solve(2) is most interesting, maybe for more applications.

Jean

Contour SOLVE [at(2) LIMITS].sm (29.92 KiB) downloaded 188 time(s).
Contour SOLVE [Electron Publish].sm (24.26 KiB) downloaded 196 time(s).
Contour SOLVE Tom MCD.sm (199.08 KiB) downloaded 230 time(s).
Contour SOLVE [user ColorMap].sm (310.53 KiB) downloaded 213 time(s).