regress, snellregress {Rvelslant} | R Documentation |
Finds the slownesses for layers given
the observed data and depth to boundaries. snellregress
is the
same except that it uses the raypath calculated by
path4sl
. The raypath is function of the slowness model, and so
this must be iterated to find a solution.
regress(z, tt, bot, theta = 0, hoffset = 0, wt = NULL, sig = NULL) snellregress(z, tt, bot, hoffset, wt = NULL, sig = NULL)
z |
array of depths of each travel time measurement. |
tt |
array of corresponding observed travel times. |
bot |
array of depth to layer bottoms. |
theta |
array of angles of incidence of the raypath for each layer. |
hoffset |
horizontal offset from the borehole. |
wt |
array of weights for the observations calculated from sig. |
sig |
the standard deviation of the observations. |
a list containing all the model parameters of the regression.
Eric M. Thompson <eric.thompson@tufts.edu>
Boore, D. M. (2003) A compendium of p- and s-wave velocities from surface-to-borehole logging: Summary and reanalysis of previously published data and analysis of unpublished data U.S. Geological Survey Open-File Report 03-191. Faraway, J. J. (2005) Linear Models with R Chapman & Hall/CRC.
snellregress
, path4sl
,
thetamatrix
# Used internally by Rvelslant()