similar to: Unexplained difference between results of dppsv and dpotri LAPACK routines

Displaying 20 results from an estimated 500 matches similar to: "Unexplained difference between results of dppsv and dpotri LAPACK routines"

2014 Dec 20
0
Unexplained difference between results of dppsv and dpotri LAPACK routines
This isn't the help list for LAPACK, but as far as I can tell, dppsv expects a symmetric matrix input compacted as triangular, not a Choleski decomposed one. So try assigning lmat before the call to dpotrf. -pd > On 20 Dec 2014, at 22:06 , Pierrick Bruneau <pbruneau at gmail.com> wrote: > > Dear R contributors, > > Considering the following sample C code, that
2010 Jan 03
3
F77_CALL, F77_NAME definition
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
2006 Apr 28
0
random NaN in dpotri result
Hello all, In a piece of c++ code (part of a future R package), I'm inverting a relatively large covariance matrix many times using: F77_CALL(dpotrf)(&upper, &xnrow, R, &xnrow, &info); F77_CALL(dpotri)(&upper, &xnrow, R, &xnrow, &info); I am sure that the input matrix is PD and inverts just fine. However, I have found that dpotri gives one or more NaNs from
2014 Dec 18
2
segfault when trying to allocate a large vector
Dear R contributors, I'm running into trouble when trying to allocate some large (but in theory viable) vector in the context of C code bound to R through .Call(). Here is some sample code summarizing the problem: SEXP test() { int size = 10000000; double largevec[size]; memset(largevec, 0, size*sizeof(double)); return(R_NilValue); } If size if small enough (up to 10^6), everything is
2010 Oct 07
2
long double, C, fortran
I'm using .Call() to call C code from R under Windows (on an Intel Core 2 duo). The C code involves some very small numbers, and I think I'm losing precision using doubles. I thought I might use long doubles to see if I can get that precision back. I have a few questions: 1. Does this affect the portability to other OSs or processors? 2. I'm returning the results in a matrix. Will
2013 Jan 31
1
Using eigen() for extracting only few major eigenpairs
Hi everyone, I am using eigen() to extract the 2 major eigenpairs from a large real square symmetric matrix. The procedure is already rather efficient, but becomes somehow slow for real time needs with moderately large matrices (few thousand lines). The R implementation statically extracts all eigenvalues (and optionally associated eigenvectors). I heard about optimizations of the eigen
2012 Sep 27
1
Problem with grid.rect
I have a stupid problem that is currently driving me crazy... Let us suppose that I want to draw a big red square in the middle of my current device (say X11) I tried the following code : pushViewport(viewport(xscale=c(0,1), yscale=c(0,1)), just=c("center", "center")) vp1 <- viewport(x=unit(0.5, "native"), y=unit(0.5, "native"), width=unit(0.4,
2010 Oct 22
2
Linking to lapack
Hello all. I'm developing a package for R holding a Gibbs sampler, which tends to have better performance when written in C than in R. During each iteration in the Gibbs sampler, I need the inverse of a symmetric matrix. For this, I wish to use lapack, as is concisely suggested in "Writing R extensions", since this will have better performance than I could ever write myself. After
2008 May 28
2
Tukey HSD (or other post hoc tests) following repeated measures ANOVA
Hi everyone, I am fairly new to R, and I am aware that others have had this problem before, but I have failed to solve the problem from previous replies I found in the archives. As this is such a standard procedure in psychological science, there must be an elegant solution to this...I think. I would much appreciate a solution that even I could understand... ;-) Now, I want to calculate a
2004 Dec 04
1
Wishlist: heatmap/image legend (PR#7402)
Full_Name: Elizabeth Purdom Version: 1.9.1 OS: Windows XP Submission from: (NULL) (171.64.102.199) It would be great if heatmap and/or image had the option of printing a legend bar on it somewhere that would indicate the ranges given by the colors in the heatmap (i.e. a very small image rectangle with the same colors as in the heatmap). Because heatmap is using layout, it seems pretty
2004 Feb 28
2
matrix inverse in C
Hi, I'm writing an R package using the C code i've written. I'm wondering if anyone knows an easy way to calculate an inverse and cholesky factor of a matrix using the Fortran/C library of R: and how to call them from C. My code is based on the Numerical Reciepe code, and I'm trying to use something that is already in R. Thanks for your help in advance, Kosuke
2010 Apr 13
1
Lapack, determinant, multivariate normal density, solution to linear system, C language
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
2010 Feb 23
2
heatmap.3
Hello again, lately I have been playing a lot with heatmap functions, in particular I complemented heatmap.2 with a nice feature from heatmap.plus, i.e. the possibility of assigning a matrix to ColSideColors so to take into account more annotations. Below is the code I introduced in heatmap.2, everything else is maintained equal to heatmap.2: if (!missing(ColSideColors)) { #if
2008 Jan 03
1
tukeyHSD
Does anybody know how to deffine in the test tukeyHSD the pairs of comparison that you want to get? It is throw the lmat commnad, but I don't know the correct usage... Thanks a lot! Jos? -- MSc Jos? Alberto F. Monteiro Botanisches Institut Universit?t Basel ?????? ?????
2013 Aug 27
1
Error in simulation. NAN
Hi all, im triyng to implement a bayesian model with R and c++. I have a strange problem. I can't reproduce the error with a small script and then i post the original one. The problem is after the line for(MCMC_iter2=0;MCMC_iter2<thin;MCMC_iter2++) For the first 34 iterations all work fine, after, all the simulations of mu_acc_P return an "nan". If i delete the line
2014 Dec 11
2
Fwd: No source view when using gdb
Dear R contributors, Say I want to debug some C code invoked through .Call() - say "varbayes" in the VBmix package. following the instructions in "Writing R Extensions", I perform the following actions : R -d gdb run library(VBmix) CTRL+C break varbayes signal 0 mod <- varbayes(as.matrix(iris)[,1:4], 2) The breakpoint is indeed activated, seemingly at the correct position
2013 Mar 08
2
Unexpected behaviour of apply()
Hello everyone, Considering the following code sample : ---- indexes <- function(vec) { vec <- which(vec==TRUE) return(vec) } mat <- matrix(FALSE, nrow=10, ncol=10) mat[1,3] <- mat[3,1] <- TRUE ---- Issuing apply(mat, 1, indexes) returns a 10-cell list, as expected. Now if I do: ---- mat[1,3] <- mat[3,1] <- FALSE apply(mat, 1, indexes) ---- I would expect a
2003 Feb 11
3
Samba getting user info from NT PDC
Hi! My boss asked me to be able to share some directories on a FreeBSD Samba server with users already created (and used) on a NT 4.0 PDC server. So I followed http://www.sugoi.org/bits/index.php?bit_id=10 I just replaced the Windows 2k part by adding the NetBIOS name of the machine to the NT PDC. When I did the smbpasswd trick it worked like charm: testsmb# smbpasswd -j CH-DOMAIN -r PDC
2020 Jul 15
2
Openblas?
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
2008 Mar 27
1
Cannot update packages on F8
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