Rx.calc                 Calculation of Source-to-Site Distance Measures
Sa.as                   Ground Motion Predictions for Individual Models
Sa.nga                  Ground Motion Predictions for all NGA Models
W.calc                  Estimation of Down-Dip Rupture Width, W
Z1.calc                 Estimation of Depth Parameter, Z1.0
Ztor.calc               Estimation of Depth to Top of Rupture, Ztor
dip.calc                Estimation of Fault Dip
interpolate             Interpolation for Intermediate Spectral Periods
mainshocks              Example Earthquake Records from the NGA
                        Flatfile
modelPeriods            Spectral Periods for NGA Models
