dofry: Fry Estimation

In geophys: Geophysics, Continuum Mechanics, Gravity Modeling

Description

Calculate the Fry diagram for estimating shear on random point patterns

Usage

dofry(x, y, PLOT = FALSE)

Arguments

x	x-coordinates
y	y-coordinates
PLOT	logical, TRUE=plot

Details

The number of points returned can be large and plotting can take a long time, so when plotting can restrict the points by using plotfry.

Value

List:

X	x-coordinates
Y	y
mx	mean X
my	mean Y

Author(s)

Jonathan M. Lees<[e-mail]>

References

Fry, N., (1979) <http://dx.doi.org/10.1016/0040-1951(79)90135-5> Random point distributions and strain measurement in rocks Tectonophysics, 60:89-105.

See Also

Showfry, plotfry, xtractlip

Examples

RDAT = randFRY(400, LIM=c(0,0, 200, 200) , rlen=5   )
length(RDAT$x)
plot(RDAT$x, RDAT$y, asp=1, pch=".", cex=2)
flag = sqrt( (RDAT$x-mean(RDAT$x))^2  + (RDAT$y-mean(RDAT$y))^2)<75

DAT = list(x=RDAT$x[flag], y=RDAT$y[flag])
 x = DAT$x
    y = DAT$y
 plot(x,y, asp=1, pch=21, col='red', bg='gold', ann=FALSE, axes=FALSE)

FF = dofry(DAT$x, DAT$y )
AF = plotfry(FF, dis=30)

Z = xtractlip(AF)

lines(cluster::predict.ellipsoid(Z$hull), col='red')  
   

geophys documentation built on May 1, 2019, 9:26 p.m.