x value at
which the function represented by
xy is equal to
yval.
NLSstClosestX(xy, yval)
sortedXyData object
y scale to get close to
x scale.
DNase.2 <- DNase[ DNase$Run == "2", ] DN.srt <- sortedXyData( expression(log(conc)), expression(density), DNase.2 ) NLSstClosestX( DN.srt, 1.0 )