points_ineq.tcl

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".

See also:

points_leq, points_geq, completer

Here is the image of the resulting surface:

Pic 1. surface with inequality conditions

This result was obtained with "examples/surfit/points/points_ineq.tcl" script.

Some comments to script:

• map_name variable is used to set name of resulting surface
• tol variable is used to manage tolerance of iterative linear system solver algorithm.

#
# This script was generated with funner v2.1beta (www.gridding.info)

# 
# load plugins
# 
load libsurfit[info sharedlibextension]

# remove all previous data and gridding rules
clear_data 

# set name of surface
set map_name "map_points_ineq" 

# set tolerance for cg solver
set tol 1e-004

##
## load initial data 
##
 
# load points from text file 
pnts_read "points_geq.txt" "points_geq"  
 
# load points from text file 
pnts_read "points_leq.txt" "points_leq"  
 
##
## construct grid 
##
grid 
 
##
## create gridding rules
##

# resulting surface should be greater than or equal to points values
points_geq "points_geq" 

# resulting surface should be lower than or equal to points values
points_leq "points_leq" 

# resulting surface should tend to be constant or plane 
completer 0 1  

##
## run gridding algorithm
##
surfit 

##
## save results 
##

# unload grid from memory
grid_unload 

# save surface to surfit datafile 
surf_save "points_ineq.dat" "map_points_ineq" 

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surfit: open source gridding and contouring software.