[R] Question on deriv3()

[Prof Brian Ripley]

Because it is not the same code.  In R, the set of known functions is 
hard-coded.  In S-PLUS, it is extensible, and was extended by MASS (now 
incorporated into the standard distribution).

On Tue, 23 Mar 2004, Mervyn G Marasinghe wrote:

> Why is deriv3() functioning differently in R from that in Splus
> using library(MASS) ? For example
> deriv3(~(t1*log(t2)+lgamma(t1)+(1-t1)*log(y)+y/t2),c("t1","t2"),function(y,t1,t2)NULL)
> complains of  lgamma.

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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