# 2.2.40 xyz_resample

## Brief Information

Resample XYZ data using a gridding method

## Command Line Usage

 1. xyz_resample iz:=Col(C) 

2. xyz_resample iz:=Col(C) y:=Col(E) 

3. xyz_resample iz:=Col(C) edge_pts:=20 

4. xyz_resample iz:=Col(C) method:=renka 

## Variables

Display
Name
Variable
Name
I/O
and
Type
Default
Value
Description
Input iz

Input

XYZRange

<active>

The input data range

Boundary Vertices y

Input

XYRange

<optional>

Vertices of the boundary curve in XY plane. If this option is null, the input data boundary will be used.

Number of Points on Edge edge_pts

Input

int

50

Edge points on the boundary

Gridding Method method

Input

int

tps

Gridding method to interpolate Z value at mesh nodes
Option list:

• renka:Renka Cline
• shepard:Shepard
• tps:Thin Plate spline
• kriging:Kriging
• wave:Weighted average

Input

int

10

The quadratic interplant locality factor for Shepard gridding method. q is used to calculate the influence radius of local approximate quadratic fitted function for each node. By default, q equals 18.

Weight Function Locality Factor nw

Input

int

18

The weight function locality factor for Shepard gridding method (w) is used to calculate the weighting radius for each node. By default, w equals 9.

Input

double

2.0

Input

double

2.0

Minimum Points min_pts

Input

int

10

Minimum control points close to the nodes

Smoothing tps_smooth

Input

double

0.0

smooth factor that specifies the extent to which the gridding surface will depart from the input data point.

Smoothing kriging_smooth

Input

double

0

smooth factor that specifies the extent to which the gridding surface will depart from the input data point.

Output oz

Output

XYZRange

<new>

See the syntax here.

## Description

Given a closed polygon boundary domain in the XY plane, this X-Function resample the XYZ data by generating interior mesh on the XY plane and interpolate the Z value by gridding. When meshing the polygon, delaunay triangulation was used.

## Examples

1. Import Resample.dat in \\Samples\Data Manipulation folder.

2. Set column C as Z and D as X column, then column D, E will be used as boundary curve.

3. Type xyz_resample -d in the command window to bring up the dialog.

4. Select column A, B, C as Input and D, E as Boundary Vertices. Enter 50 to the Number of Points on Edge box.

5. Click OK to run the X-Function.

## Algorithm

Detail algorithms please read the NAG help, d06 - Mesh Generation and help of XYZ Gridding Methods

## References

George P. L and Borouchaki H (1998). Delaunay Triangulation and Meshing: Application to Finite Elements. Editions HERMES, Paris.

Keywords:mesh