DESCRIPTIONThis module computes the gradient of data on a lattice of any type, up to three dimensions. It creates an output lattice with the same coordinates as input, with data being the computed gradient vectors.
The module uses central differencing for uniform and perimeter lattices, and NAG routines for curvilinear lattices. The NAG routines employ a quadratic Shepard method that handles duplicate points and coplanar points.
This module is meant as a replacement for Gradient and Gradient3D.
Port: Lattice In
The input lattice.
A scale factor to be applied to the output vector.
If the input data is a vector, this selects the data channel.
The output lattice of vectors.
KNOWN PROBLEMSThe curvilinear routines are considerably slower than the uniform and perimeter routines.
© The Numerical Algorithms Group Ltd, Oxford UK. 2000