[R] boundary constraints with smooth.spline

[Will Sheffler]

Hi R Community.

I would like to use smooth.spline to fit a set of data and constrain the 
endpoints of the fit to have specific derivatives. I know this is 
possible with cubic splines, but I can't figure out how to specify this 
with arguments to the smooth.spline function. In general, is it possible 
to specify a set of "knots" w/locations and derivatives to constrain the 
fit? I can't find anything about this is the documentation.
Thanks!

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Will Sheffler
Baker Lab
Dept of Genome Sciences
University of Washington
Seattle, WA 98195