erf: Error Function
In geophys: Geophysics, Continuum Mechanics, Gravity Modeling

Description Usage Arguments Details Value Author(s) See Also Examples

Error Function

erf(x)
philpotts.erf(x)
erfc(x)
erfinv(x)

x

Uses pnorm to calculate the error function. erfinv returns the inverse of the erf function.

error function

Jonathan M. Lees<jonathan.lees@unc.edu>

philpotts.erf

j = seq(from=0, to=5.5, by=0.01)
 y = erf(j)   
phil = philpotts.erf(j)

 plot(j,y)
points( j, phil, pch=3, col='red'  )


#### plot the difference
plot(j, y-phil)
lines(j, y-phil)


#####  inverse of erf function:

 j = seq(from=0, to=5.5, by=0.1)
 y = erf(j)

for(i in 1:length(j))
   {

     z = erfinv(y[i])
     print(paste(i, y[i], j[i], z, sep=" "))
   }