Thanks to all! Sincerely, Erin
On Wed, May 7, 2008 at 10:35 PM, Simon Blomberg <[EMAIL PROTECTED]> wrote: > No, computer algebra systems such as yacas do symbolic differentiation. > Automatic differentiation is a numerical technique that can be used to > find derivatives of functions that can be implemented as computer > programs, through successive uses of the chain rule on the computer code > itself. It would be cool if R could either do AD or interface to an AD > package. R can be used with ADmodelbuilder (see > http://otter-rsch.ca/admbre/examples/glmmadmb/glmmADMB.html) , a > proprietry program, but an open source solution would be nice. > > Cheers, > > Simon. > > > On Thu, 2008-05-08 at 03:09 +0000, David Winsemius wrote: > > "Erin Hodgess" <[EMAIL PROTECTED]> wrote in > > news:[EMAIL PROTECTED]: > > > > > Is there a package for automatic differentiation, please? > > > > > > > Have you looked at Goedman, Grothendieck, Hojsgaard, and Pinkus' Ryacas? > > > > >From the Ryacas documentation: > > Analytical derivatives of functions can be evaluated with the D() and > > deriv() functions: > > > > > yacas("D(x) Sin(x)") > > > > expression(cos(x)) > > > -- > Simon Blomberg, BSc (Hons), PhD, MAppStat. > Lecturer and Consultant Statistician > Faculty of Biological and Chemical Sciences > The University of Queensland > St. Lucia Queensland 4072 > Australia > Room 320 Goddard Building (8) > T: +61 7 3365 2506 > http://www.uq.edu.au/~uqsblomb > email: S.Blomberg1_at_uq.edu.au > > Policies: > 1. I will NOT analyse your data for you. > 2. Your deadline is your problem. > > The combination of some data and an aching desire for > an answer does not ensure that a reasonable answer can > be extracted from a given body of data. - John Tukey. > > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > -- Erin Hodgess Associate Professor Department of Computer and Mathematical Sciences University of Houston - Downtown mailto: [EMAIL PROTECTED] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.