A program to take the difference of two v.in files having the same number and position of boundary and velocity nodes

**Files**

Input file: v1.in is the input file v.in containing the velocity model used by RAYINVR Input file: v2.in is the input file v.in containing the velocity model used by RAYINVR Output file: vdiff.out contains the difference between the files v2.and v1.in; it has the same x-coordinates as v1.in and v2.in, but the difference of the v2.in values minus the v1.in values for each boundary depth and velocity The value of xmax is input interactively. The main purpose of VDIFF is to allow the resolution of a final model to be tested by observing how the perturbation of a single model parameter is "smeared" into adjacent parameters. To do this, the difference between the original final model and the final model obtained after inverting the data generated by the final model with a single parameter perturbation is taken. VDIFF may also be used to compare a final model with the true model in a synthetic test.

Sat Mar 7 19:13:54 EST 1998