similar to: matrix algebra in c

I am experiencing some odd behavior with the .Call interface, and I am hoping someone out there can help me with it. Below is a simple example (in that there are R packages that do exactly what I want), but this code illustrates the problem. Thanks in advance for any help you can provide. Suppose I want to compute the log density of a multivariate normal distribution using C code and the gsl

I have an upcoming JASA paper with an iid sampling algorithm for Bayesian Generalized Linear models (e.g., Logit, Poisson Regression, and Conditional Logit models with multivariate normal priors). At this point, I have implemented the algorithms in C and hope to make the functions and corresponding source code available through an R package. I have successfully created the code necessary to

I give up. Maybe it is my search (Windows) but I cannot seem to find the definition of the F77_CALL or F77_NAME macros. Either there are too many matches or the search just doesn't find it. For example where is the source for: F77_CALL(dpotri) ? Thank you. Kevin

Dear All, I have just updated R to the version 2.6.2 on F8 (with the official F8 rpm). However, when running as root the following command: update.packages(checkBuilt=T) I get a bunch of errors like the ones below. Any ideas? Thanks in advance, Paul ----------------------------------------------- * Installing *source* package 'nlme' ... ** libs gcc -m32 -std=gnu99 -I/usr/include/R

Dear R contributors, Considering the following sample C code, that illustrates two possible uses of a Cholesky decomp for inverting a matrix, equally valid at least in theory: SEXP test() { int d = 2; int info = 0; double mat[4] = {2.5, 0.4, 0.4, 1.7}; double id[4] = {1.0, 0.0, 0.0, 1.0}; double lmat[3]; F77_CALL(dpotrf)("L", &d, mat, &d, &info); lmat[0] = mat[0]; lmat[1]

On 2020-07-15 14:36, Dirk Eddelbuettel wrote: > > G?ran, > > This is not an easy email to reply to because it _contains nothing > reproducible_. Thanks Dirk, Sorry about that, but my real question was (see below): "Is the problem that openblas uses C versions of blas?" That is, do I need to change F77_CALL(name)(...); to cblas_name(...); everywhere? And if so, is

Hi I am new to writing C code and am trying to write an R extension in C. I have hit a wall with F77_CALL(dgemm) in that it produces wrong results. The code below is a simplified example that multiplies the matrices Ab and Bm to give Cm. The results below show clearly that Cm is wrong. Am= 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Bm= 1 1 1 1 1

In my package 'glmmML' I'm using old C code and linpack in the optimizing procedure. Specifically, one part of the code looks like this: F77_CALL(dpoco)(*hessian, &bdim, &bdim, &rcond, work, info); if (*info == 0){ F77_CALL(dpodi)(*hessian, &bdim, &bdim, det, &job); ........ This usually works OK, but with an ill-conditioned data

Dear R-devel, I've written a numerical solver for SOCPs (second order cone programs) in R, and now I want to move most of the solver code into C for speed. I've written combined R/C packages before, but in this case I need to do matrix operations in my C code. As I have never done that before, I'm trying to write some simple examples to make sure I understand the basics. I am stuck

Professor Ripley commented on LAPACK error codes: https://stat.ethz.ch/pipermail/r-help/2007-March/127702.html and says "Internal LAPACK errors are usually problems with arithmetic accuracy, and as such are compiler- and CPU-specific." Is there a listing for the error codes from Lapack routine 'dsyevr'? Especially I am interested about the meaning and handling of error codes 1

Dear R-devel, I am trying to use Fortran DGESV subroutine into C. Here it is the relevant part of the C file I am currently writing #include<stdio.h> #include<R.h> #include<Rmath.h> #include<math.h> void F77_NAME(DGESV)( int*, int*, double*, int*, int*, double*, int*, int*); void solve( int *p, double *A, double *Ainv) { ... F77_CALL(DGESV)(p, p, Ain, p, ipiv,

Dear list, I am a little puzzled by computing time in connection with calling C functions. With the function mysolve1 given below I solve Ax=B, where the actual matrix operation takes place in mysolve2. Doing this 5000 times takes 3.51 secs. However, if I move the actual matrix inversion part into mysolve1 (by uncommenting the two commented lines and skip the call to mysolve2) then the

> > On 9 Feb 2017, at 16:00, G?ran Brostr?m <goran.brostrom at umu.se> wrote: > > > > In my package 'glmmML' I'm using old C code and linpack in the optimizing procedure. Specifically, one part of the code looks like this: > > > > F77_CALL(dpoco)(*hessian, &bdim, &bdim, &rcond, work, info); > > if (*info == 0){ > >

> On 10 Feb 2017, at 14:53, G?ran Brostr?m <goran.brostrom at umu.se> wrote: > > Thanks to all who answered my third question. I learned something, but: > > On 2017-02-09 17:44, Martin Maechler wrote: >> >>>> On 9 Feb 2017, at 16:00, G?ran Brostr?m <goran.brostrom at umu.se> wrote: >>>> >>>> In my package 'glmmML'

Hello, I thought that I should try openblas when building a CRAN package containing lots of old (twentieth century) C-code with frequent calls to blas and lapack routines. I have the following options on my Ubuntu 20.04 machine: Selection Path Priority Status ------------------------------------------------------------ * 0

Hello, I am trying to call the BLAS Level1 function zdotc from R via a .C call like this: #include "R.h" #include "R_ext/BLAS.h" void testzdotc() { Rcomplex zx[3], zy[3], ret_val; zx[0].r = 1.0; zx[0].i = 0.0; zx[1].r = 2.0; zx[0].i = 0.0; zx[2].r = 3.0; zx[0].i = 0.0; zy[0].r = 1.0; zy[0].i = 0.0; zy[1].r = 2.0; zy[0].i = 0.0; zy[2].r = 3.0;

I'm trying to figure out why the presence of a Fortran call affects the result of a floating-point operation. I have C functions void test1(int *n, double *f){ int outC; double c0; c0 = (double) *n * *f; outC = floor(c0); printf("when f computed by R, C says %d by itself\n",outC); } void test2(int *n, double *f){ extern int F77_NAME(ifloor)(double *); int

This is a multipart message in MIME format. --=_alternative 00812CFCCA256D66_= Content-Type: text/plain; charset="us-ascii" Two points in respect to PR#2867. First, the trivial one: (1) In Lapack.c, on lines 806 and 812, there are calls of F77_CALL(dgeqp3). But the error messages on lines on lines 809 and 815 refer to "dqeqp3", i.e., they currently have a "q"

I have ported some R code to C to make it faster. I can perform .Call("foobar",....) once and it works fine. Absolutely correct answer. If I put a loop inside foobar and run the main code routine more than 100 times, it crashes R. Or if I call .Call("foobar"....) seperately more than two tims it crashes R. For the most part I am doing matirx multiplies using EXP

r-devel list, I have recently written an R package that solves a linear least squares problem, and computes the multivariate normal density function. The bulk of the code is written in C, with interfacing code to the BLAS and Lapack libraries. The motivation here is speed. I ran into a problem computing the determinant of a symmetric matrix in packed storage. Apparently, there are no explicit