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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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Calling MATLAB's built-in LAPACK/BLAS routines

I want to learn how to call the built-in LAPACK/BLAS routines in MATLAB. I have experience in MATLAB and mex files but I've actually no idea how to call LAPACK or BLAS libraries. I've found the gateway routines in file exchange that simplifies the…
petrichor
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Any reason why Octave, R, Numpy and LAPACK yield different SVD results on the same matrix?

I'm using Octave and R to compute SVD using a simple matrix and getting two different answers! The code is listed below: R > a<-matrix(c(1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,1,1,1), 9, 4) > a [,1] [,2] [,3] [,4] …
Clive
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Use BLAS and LAPACK from Eigen

I've implemented a piece of code with Eigen and I would like Eigen to use BLAS and LAPACK . I've seen here, that is possible but I don't know how or where to put those values/directives in the code. I have to expecify somewhere the value…
Santi Peñate-Vera
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Julia Memory Allocation for Addition of Two Matrices in place

I'm curious why Julias implementation of matrix addition appears to make a copy. Heres an example: foo1=rand(1000,1000) foo2=rand(1000,1000) foo3=rand(1000,1000) julia> @time foo1=foo2+foo3; 0.001719 seconds (9 allocations: 7.630 MB) julia>…
Lindon
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Best C++ Matrix Library for sparse unitary matrices

I am looking for a good (in the best case actively maintained) C++ matrix library. Thereby it should be templated, because I want to use a complex of rationals as numerical type. The matrices what I am dealing with are mainly sparse and unitary. Can…
Mathias Soeken
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How to compile VAMP Plugins to iOS ARMV7

VAMP Plugins by Queen Mary University of London is an amazing collection of BSD licensed software. All these plugins are at the basis of the Sonic Visualizer software A plug Sdk to build plugins is available as well. You can build the plugins for…
loretoparisi
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C++ Memory Efficient Solution for Ax=b Linear Algebra System

I am using Numeric Library Bindings for Boost UBlas to solve a simple linear system. The following works fine, except it is limited to handling matrices A(m x m) for relatively small 'm'. In practice I have a much larger matrix with dimension m=…
neversaint
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Armadillo + BLAS + LAPACK: Linking error?

When I try to compile example1.cpp that comes with Armadillo 2.4.2, I keep getting the following linking error: /tmp/ccbnLbA0.o: In function `double arma::blas::dot(unsigned int, double const*, double…
Marc
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Dense Cholesky update in Python

Could anyone point me to a library/code allowing me to perform low-rank updates on a Cholesky decomposition in python (numpy)? Matlab offers this functionality as a function called 'cholupdate'. LINPACK also has this functionality, but it has (to my…
user1116403
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lapacke or clapack if programming in c/c++ in linux

My purpose of using LAPACK is to calculate the cholesky of a matrix. I am programming in C/C++ in Fedora, but I am confused over which lapack to install - LAPACK with lapacke or clapack?
cyw
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LAPACK/BLAS versus simple "for" loops

I want to migrate a piece of code that involves a number of vector and matrix calculations to C or C++, the objective being to speed up the code as much as possible. Are linear algebra calculations with for loops in C code as fast as calculations…
behzad.nouri
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Installing Lapack on PHP

I am trying to install Lapack to use it with PHP (http://php.net/manual/en/book.lapack.php) as it is the only PHP library that I have found that contains computations for singular values. I am on a Ubuntu 14.04 server with Apache2. I have installed…
MemoNick
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How to solve large-scale nonlinear optimization problems with Ceres?

I need to optimize a surface represented by a 2D grid of points to produce normal vectors of the surface that align with provided target normal vectors. The grid size is likely to be between 201x201 and 1001x1001. That means that the number of…
Eric
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I get "lapack.h: No such file or directory" although I installed liblapack-dev

I installed liblapack-dev and its dependencies using Synaptic, and I included in my code. If I try to compile my program like this... mpicc program.c -llapack -o output ...I get the following error: program.c:4:20: fatal error:…
iCanLearn
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Time complexity of scipy.linalg.solve (LAPACK gesv) on large matrix?

If I use scipy.linalg.solve (which I believe calls LAPACK's gesv function) on a ~12000 unknown problem (with a ~12000-square, dense, non-symmetrical matrix) on my workstation, I get a good answer in 10-15 minutes. Just to probe the limits of what's…
timday
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