NLSstClosestX              package:nls              R Documentation

Inverse Interpolation

Description:

     Use inverse linear interpolation to approximate the `x' value at
     which the function represented by `xy' is equal to `yval'.

Usage:

     NLSstClosestX(xy, yval)

Arguments:

      xy: a `sortedXyData' object

    yval: a numeric value on the `y' scale

Value:

     A single numeric value on the `x' scale.

Author(s):

     Jose Pinheiro and Douglas Bates

See Also:

     `sortedXyData', `NLSstLfAsymptote', `NLSstRtAsymptote',
     `selfStart'

Examples:

     data( DNase )
     DNase.2 <- DNase[ DNase$Run == "2", ]
     DN.srt <- sortedXyData( expression(log(conc)), expression(density), DNase.2 )
     NLSstClosestX( DN.srt, 1.0 )

