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Message-ID: <Pine.LNX.4.58.0503021012340.11227@moon.stats.gla.ac.uk>
Date: 2005-03-02T10:14:52Z
From: Simon Wood
Subject: constraining initial slope in smoother.spline
In-Reply-To: <002301c51e7e$4a18a990$ae1ad284@BIO041>

> 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