This example shows how to use inequality conditions in points to obtain evenly sampled surface. Here we have two set of points: blue (points_geq) and red (points_leq). For blue points surface should be greater than or equal to points values, for red "less than or equal".
Here is the image of the resulting surface:
Pic 1. surface with inequality conditions
This result was obtained with
Some comments to script:
surfit: gridding and contouring software.