Krig

Synopsis

Advanced interpolation modules using polynomial and statistically based kriging methods in 3D.

Input Ports

Name	Type	Description

in_fld	Mesh+Node_Data	3D scatter points

Parameters

Name	Type	Description

nx	int	number of grid nodes in x direction
ny	int	number of grid nodes in y direction
nz	int	number of grid nodes in z direction
radius	float	search radius

Output Ports

Name	Type	Description

zest	float[][][]	estmated values at grid nodes
zstd	float[][][]	standard deviation at grid nodes

Description

The Krig set of modules perform scatter to grid interpolation. They are based on the Toolmaster interpolation system, using both simple and Kriging methods. As these routines are already part of the AVS/Express runtime environment, these modules provide high-level Field wrappers around these interpolation functions. Three macro modules are provided in this Krig library:

Krig - Interpolation from 3D scatter points and data values to a Kriging 3D grid.

Estimates a random function of 3 variables at all grid nodes belonging to a 3D regular grid using the method of Kriging. The random function estimate and standard deviation arrays are calculated at all grid nodes. The semi-variogram function "gam" is supplied in this project and may be configured as needed with re-compilation.

Inputs

in_fld

3D scatter points which combine a mesh and some node data. A Node_Data object represents the values of some dataset at the node points of a field, while the Mesh represents the locations of that field's nodes in space.

Outputs

zest

3D float array. This array contains the estimated values at the grid nodes.

zstd

3D float array. This array contains the standard deviations t the grid nodes.

Utility Macros

The Krig2D macro uses the XuKrigging3D low-level module. This modules uses the XuKriging3DCalc and other functions of the the Toolmaster agX library.

Example

Two example applications are applied, KrigEg0 and KrigEg1. The KrigEg0 application demonstrates how 3D scatter points can be interpolated into uniform 3D grid. KrigEg1 is similar to KrigEg0, but adds a crop macro to show the boundary of 3D grid.

Files

iac_proj/krig/krigmods.v contains the V definition of the agxint,XuKrigging2D and XuKrigging3D modules.

iac_proj/krig/krigmacs.v contains the V definitions of the Krig2D,Interp2D and Krig macros.

iac_proj/krig/krigapps.v contains the V definition of the KrigApps example application.

Other Notes

See the documentation for XuKriging2DCalc, XuKriging3DCalc, XuGriddingLocalFitCalc in the Toolmaster agX Reference Manual.

Authors

Mark Lambert, Roger Fleuty, Ian Curington

Advanced Visual Systems, Inc.

Modifications

Ma YingLiang,
Manchester Visualization Centre

Andrew Dodd,
International AVS Centre

Contact

International AVS Centre
Manchester Visualization Centre
Manchester Computing
University of Manchester
Oxford Road
Manchester
United Kingdom
M13 9PL