The math module can be used in multiple ways. Below are three ways to use the Math module.
The math module can be used to truncate a 3D grid with a 2D grid. Using grid A and grid B, the expression IF (Z < B, 0, A) tells Voxler if Z is less than the value in grid B, set the data value to 0, else use the value in grid A.
The math module can be used to blank a vertical region of a grid file. Create a GRD file in Surfer (or another program) with the Z value set to the X coordinate. Load the GRD file in Voxler and use a Math module to set the data values to 0 if the X values in the Voxler Gridder module output are less than the data values in the GRD file. Use an IF function with the syntax IF Z > B, 0, A OR Z > B? 0:A. With a GRD file, the elevation data is imported as component 1. Both syntax statements say to set the output value to 0 if the Z value is greater than the elevation data in the GRD file ("B"). If the Z value is less than the elevation in value in B, use the data value in A. The value of 0 is used in this example, 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 value to be transparent in the Colormap editor to complete the blanking procedure.
The math module can be used to blank a horizontal region to the left or right of an X value in a BLN file. Remove the BLN header, save to a DAT file, then grid the DAT file using the X column for the Z value. Attach a Gridder module and GRD file, and change the reference in the Math equation from Z to X, making the syntax X > B? 0:A.
The math module can be used to perform math functions, such as adding, subtracting, multiplying, or dividing, values from multiple lattices. For instance, if you have loaded two data files and gridded both, you can use an Math module with both Gridders as the input lattices. Then, set the expression to A+B to add the component values from the two grids.
Sometimes, it is desirable to compute values based on multiple components. For instance, your drill data may have porosity, permeability, gamma, resistivity, and other components. To determine where to place the next drill hole, you may want to combine multiple components and map the composite. To do this, attach the lattice to a Math module. You can then use an equation such as (A1+A2)*A3 to add two components and multiple that value by a third component. This new lattice can then be used to create a volrender showing the composite information.
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