Assign a Null or NoData value to a lattice above an irregular topography surface in Voxler

• 3D Voxler Features Now in Surfer
• Surfer New Feature: 3D Gridding
• Surfer New Feature: 3D Volume Render & Isosurfaces
• Create a Drillhole map in Surfer
• Assign NoData to 3D Grid

How to assign a null value to a Voxler lattice

Attach the 3D lattice as input "A" and a GRD file with the topography as input "B" to the input of the Math module.

Note: The GRD file must be imported as a uniform lattice.

Use an IF function in one of the below formats:

IF Z > B, 0, A 

Or 

Z > B? 0:A

With a GRD file, the elevation data is imported as component 1.

Both statements say to set output value to 0 if the Z value is greater than the elevation data in the GRD file (or "B"). If the Z value is less than the elevation value in B, use the data value in A. In this example, a value of 0 is used, but any value less than the Z minimum of the data can be used.

Connect a VolRender module to the output of the Math module, and set the 0 values to be transparent in the Colormap Editor accessed via the ellipsis button [...] to the right of the Colormap example in the VolRender Property Manager.

Blank a lattice above a GRD surface.

The same principle can be applied to blanking to the right of an X value in a BLN file.  Remove the BLN header, save to a DAT file in Surfer, and grid the DAT file using the X column for the Z value.  In Voxler, attach the Gridder module and GRD file to a Math module as above, and change the reference in the Math equation from Z to X:

X > B? 0 : A

Blank a lattice to the right of an X value in a BLN file.

 

 

 

Updated January 7, 2019