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Questions tagged [lapack]

LAPACK (Linear Algebra PACKage) is a software library package to solve linear algebra equations. LAPACK is written in Fortran 90.

LAPACK provides routines for solving systems of simultaneous linear equations, least-squares solutions of linear systems of equations, eigenvalue problems, and singular value problems. LAPACK is written in Fortran 90.

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Linking C++ with BLAS and LAPACK

To call a Fortran routine from c++ I have been using: extern "C" void routinename_(...) with the appended underscore making this compatible with a Fortran subroutine name "ROUTINENAME". When I link c++ with BLAS or LAPACK it only works WITHOUT the…
user99439
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Using lapack in C

I am working on understanding a fellow physicist's code in C that uses Lapack, which I have never used before. I used sudo apt-get to install lapack. and I've been compiling with gcc -llapack Dirac.c -o Dirac -lm and I'm getting the compiling…
Beth
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Link error undefined reference to `dgels_' in Lapack

I followed this below webpage to install ATLAS + Lapack in linux : http://math-atlas.sourceforge.net/atlas_install/node6.html bunzip2 -c atlas3.10.1.tar.bz2 | tar xfm - # create SRCdir mv ATLAS ATLAS3.10.1 # get unique…
barfatchen
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Compute the eigenvectors in lapack using predetermined eigenvalues?

I have a rather unusual challenge for lapack, and I have spent hours searching for a solution to it. I have a generalized eigenvalue problem of the traditional form (A - x B = 0). Normally I would use for instance ?hegvx or ?hegvd to calculate the…
Smidstrup
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Solving a banded system from C using LAPACK's DGBSV

I have tried to search for a similar thread related to this topic, but nobody seems to care for banded systems (...). I am interested in solving a banded matrix using LAPACK/ScaLAPACK from a C code. First, I want to achieve a sequential solution…
Eduardo
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BLAS DGEMM: Can I pass C as A or B?

I want to perform a string of matrix multiplies, and would prefer not allocate a fresh matrix if I can avoid it. For example, I want to compute C = C * B (so I pass in C as A and C) Can I do this (due to dgemm having marked both A and B as in…
Steven Lu
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R lapack routines cannot be loaded

I usually ran different statistical analysis in R with routines that use lapack like gam() lm(), etc but after several updates of libraries the following error appears: library(mgcv) This is mgcv 1.7-22. For overview type…
Leosar
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Need help installing LAPACK/BLAS for CVXOPT (or a recommendation for another QP solver that's easier to install)

I've been trying to install CVXOPT, which requires LAPACK/BLAS and to be honest it's killing me! Context: I am experimenting with an SVM and so need a QP solver. CVXOPT seems to be the best. The problem is the LAPACK/BLAS (or ATLAS) dependency.…
iRoygbiv
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Lapack's row reduction

I am trying to write a function that produces a single solution to an underrepresented system of equations (e.g. the matrix that describes the system is wider than it is tall). In order to do this, I have been looking in the LAPACK documentation for…
Litherum
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f2py: Wrapping fortran module which makes use of subrouines distributed in different files?

For reasons I described earlier, I need to use LAPACKs dgesvd and zgesvd methods in Python instead of the ones wrapped in numpy. Someone pointed out, that I could use f2py, to create my own python package. The trouble is, that, dgesdd in lapack…
Mischa Obrecht
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linking lapack issue

I am trying to compile a program that uses lapack. First, I installed lapack by installing all the packages using 'sudo apt-get install' on this link: https://launchpad.net/ubuntu/precise/+source/lapack I am trying to compile the code on this…
db1234
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Find eigenvalues of boost matrix with LAPACK

I'm having trouble finding the eigenvalues of a boost matrix using the boost LAPACK bindings. This is my best guess: template boost::numeric::ublas::vector diagonalize(const boost::numeric::ublas::matrix& input) { // create a…
Johannes Ferber
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LAPACK fails calculating eigenvectors

I wrote some code to solve the general eigenvalue problem and now I am comparing my results against LAPACK's DSPGVX function. I just worked with this example. So I obtained the 4 auto vectors { {-0.0319133, -0.265466, -0.713483, 0.64765}, …
Open the way
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I'm getting zero values using dstev to calculate eigenvectors

I use gcc to compile under mac os x, I have Intel's mkl_lapack.h library installed. In the program I have a NxN tridiagonal matrix, so I just use two vectors to store values of the matrix. "d" vector is the main diagonal, the values of subdiagonals…
Ramy Al Zuhouri
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memory leak in dgemm_

I am currently working on an application which involves lots and lots of calls to blas routines. Routinely checking for memory leaks I discovered, that I am loosing bytes in a dgemm call. The call looks like this: // I want to multiply 2 nxn…
chris.schuette
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