Computing Grid Residuals

RockWorks | ModOps | Grid | Statistics | Residuals

Use this program to compute the difference between observed Z values (listed in the datasheet) and computed Z values in an existing grid model. Both the model's Z values at the listed X,Y points and the residuals will be listed in columns in the datasheet.

! This program requires that the source data, from which the grid model was computed, be displayed in the main RockWorks Datasheet.

See also the Scattergram program for a scatter diagram that will display observed data values versus computed node values.

Menu Options
Step-by-Step Summary

  1. Access the RockWorks Datasheet program tab.
  2. Open the XYZ data from which the grid model was created. This is necessary because the program needs to know the original observed values against which the grid model values will be compared.
  3. Select the ModOps | Grid | Statistics | Residuals menu option.
  4. Enter the requested menu settings, described above.
  5. Click the Proceed button to continue.

The program will read the original data values from the main data sheet. It will determine the calculated grid model Z-values for each control point location and compute the difference of observed minus grid values. The grid model values and residual values will be listed in the selected datasheet columns.

TIP: Use the Utilities | Statistics | Histogram program to display the range of residual values. This gives a nice display of the accuracy of the model's nodes.

Back to Grid Menu Summary

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