Yes, as Charlie said you can write a small C wrapper that calls R. The C wrapper can then be called from Fortran.
For some examples: see the package minpack.lm (http://cran.r-project.org/web/packages/minpack.lm/index.html); the C wrappers are the functions fcn_lmdif and fcn_lmder.c. Maybe more transparently: see the package minqa on R-forge (https://r-forge.r-project.org/src/contrib/minqa_1.0.tar.gz) There an objective function in Fortran looks like this: SUBROUTINE CALFUN (N,X,F) call resfun(N, X, F); RETURN END and resfun is a simple C function that evaluates a call to an R function. On Thu, 19 Nov 2009, Charlie Sharpsteen wrote: > On Thu, Nov 19, 2009 at 12:14 PM, Paul Warren Simonin > <paul.simo...@uvm.edu> wrote: > > > > > > ? Hello, > > > > ? ? I am currently working on a modeling project using Fortran to run > > large repetitive loops (many DO loops). As part of this process I > > would like to use a model fit in R and currently stored as an R > > object. This is a rather complex model, a GAMM, and I am curious > > whether there is a way to call this model from Fortran. I am not sure > > "call" is correct terminology, but I would basically like to use this > > GAMM to make a prediction as part of each DO loop. Is this possible? I > > have found instructions, etc. for calling Fortran from R but not vice > > versa. > > > > ? ? Thank you for any information or advice. General advice to > > address this situation is also welcome. > > > > ? Thanks again! > > > > ? -Paul Simonin > > > The R library and interpreter are written in C and available using a C > interface. Therefore, it would be theoretically possible to call > this interface from Fortran-- however there are details that probably > make a direct call impossible in practice. This is because > interfacing with R requires passing representations of R objects > (SEXPs) which are far removed from the basic C variable types > supported by standardized C--Fortran interfaces. > > It may be that the only plausible way to approach this problem may > involve writing a set of bindings in C that interface with R and > extract the information you are interested in and then express it > using basing C variables that Fortran can understand. With such a > system in place your Fortran program would call a set of routines > written in C that called routines from the R libraries and then > reformatted the results and returned them to Fortran. > > This is a conclusion based on my limited experience-- not any formal > expertise. There are definitely others on this list that could > provide a better qualified answer. > > Good luck! > > -Charlie > > ______________________________________________ > 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. >
______________________________________________ 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.
