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Questions tagged [umfpack]

UMFPACK is a set of routines for solving unsymmetric sparse linear systems, Ax=b, using the Unsymmetric MultiFrontal method.

UMFPACK is a set of routines for solving unsymmetric sparse linear systems, Ax=b, using the Unsymmetric MultiFrontal method.

http://www.cise.ufl.edu/research/sparse/umfpack/

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Scipy sparse invert or spsolve lead to UMFPACK_ERROR_OUT_OF_MEMORY

I am trying to invert a large (150000,150000) sparse matrix as follows: import scipy as sp import scipy.sparse.linalg as splu #Bs is a large sparse matrix with shape=(150000,150000) #calculating the sparse inverse iBs=splu.inv(Bs) leads to the…
laila
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Is there any efficient way to dynamically change the compress_matrix in boost?

I am using ublas::Compressed Matrix to work with UMFPACK, a sparse linear solver. Since I am doing a simulation, so every time the linear system is constructed slightly differently that might involve enlarging/shrinking the coefficient matrix and…
He01
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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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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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'umfpack.h' not found, but it's in /opt/local/include/

I'm trying to compile a program called hiQlab on OSX 10.8 g++ -g -O2 -I`echo /Users/.../Documents/hiQlab/hiqlab-2006-07-20/tools/`/lua/include -I`echo /Users/.../Documents/hiQlab/hiqlab-2006-07-20/tools/`/tolua++/include -c…
user2924321
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Recommended direct solver for sparse positive definite linear system in scipy?

I'm sorry if this is explained clearly in the scipy.sparse documentation. When using scipy, what function would you recommend using to solve a sparse positive definite linear system of equations? I want to use a direct method, and I want the…
littleO
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In UMFPACK, how often do we need to do symbolic and numeric factorization?

I have a system Ax = b, where B is a constant, but A keeps changing by small amounts in each iteration. I am using UMFPACK 5 to solve this linear system again as again as A changes. I can do the above in two ways: Compute the symbolic and numeric…
Chatter
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UMFPACK and BOOST's uBLAS Sparse Matrix

I am using Boost's uBLAS in a numerical code and have a 'heavy' solver in place: http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl?LU_Matrix_Inversion The code works excellently, however, it is painfully slow. After some research, I…
ccook
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Improving the solution of sparse linear systems

I have written a code in C++ on a Linux system which solves the linear system A x = b, where A is a sparse symmetric matrix using the following two approaches: Using UMFPACK to sequentially factorize and do backward forward substitution. Using…
yassine93
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Solving a system with UMFPACK where x = (AtA)^-1 b

I have a sparse matrix A, and need to solve the system (AtA)X = B. Right now I'm multiplying At by A and using AtA to solve the system. Is there a faster alternative (like passing A to UMFPACK and have it find the factorization quicker)? A is…
Jordi
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Build dll for large C project with makefile

I'm trying to build simple dll which uses library UMFPACK. Here is my file "umfsolver.c": #include #include #include "umfpack.h" #include "amd.h" #define MAX(a,b) (((a) > (b)) ? (a) : (b)) #ifdef BUILD_DLL #define EXPORT…
TKireev
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Module not found error when importing umfpack MacOS Monterey M1 chip

I installed umfpack using pip install scikit-umfpack and tried importing the umfpack module from scikits import umfpack I'm running into the following error: Traceback (most recent call last): File…
Christian Adib
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Apparent incompatibility of Python Poetry with scikit-umfpack

I have written a package that depends on scikit-umfpack and just discovered Python Poetry. I am trying to setup the .toml file for poetry to manage umfpack. When typing poetry add, it is suggested to use scikit-umfpack version 0.3.2, so it seems…
chandail_ocre
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solving sparse Ax=b in scipy

I need to solve Ax=b where A is the matrix that represents finite difference method for PDEs. Typical size of A for a 2D problem is around (256^2)x(256^2), and it consists of a few diagonals. The following sample code is how I construct A: N = Nx*Ny…
Physicist
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umfpack: An error occurred: numeric factorization: not enough memory

I'm having a problem while running a Scilab code. As title suggests, I get the error numeric factorization: not enough memory, related to the umfpack function. In task manager I see a memory usage around 3GB (my system has 16GB). Can anyone help me…
Gerlando Sciortino
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