DESCRIPTION

v.bspline makes a bilinear/bicubic interpolation with Tykhonov regularization. The required input is a vector of only points that will be used for interpolate a reference surface. If an extra input vector is used, an estimation using the reference surface will be done on the points of this last vector. In other case, the interpolation will be done with the points of the former vector. The output format can be a vector in which case the interpolation will be done on the sparse points, or a raster map. In this last case, the interpolation will be on a regular grid.

EXAMPLES

Basic interpolation

v.bspline input=point_vector output=interpolate_surface type=bicubic
In this case, a bicubic spline interpolation will be done and an estimation of the points of vector will be the output.

Basic interpolation and raster output with a long spline step

v.bspline input=point_vector raster_out=interpolate_surface sie=25 sin=25
Now, a bilinear spline interpolation will be done on a grid.

Estimation on sparse points

v.bspline input=point_vector int_ext=sparse_points output=interpolate_surface
In this last case, an estimation of the point within sparse points will be done using the parameters estimated with the points of point_vector.

SEE ALSO

AUTHORS

Original version of program in GRASS 5.4:
Maria Antonia Brovelli, Massimiliano Cannata, Ulisse Longoni, Mirko Reguzzoni

Update for GRASS 6.X:
Roberto Antolin

Last changed: $Date: 2006/08/22 21:24:11 $