[R] constraining initial slope in smoother.spline

[Simon Wood]

> Hello.  I want to fit a smoother spline (or an equivalent local
> regression method) to a series of data in which the initial value of the
> 1st derivative (slope) is constrained to a specific value.  Is it
> possible to do this?  If so, how?

- you should be able to modify the example in the help file for 
mgcv::pcls, to do this. The example uses inequality constraints to impose 
monotonicity on a smooth, but the routine will also accept equality 
constraints.

Simon