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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Problems with zheev routine in fortran

I'm trying to write a program which computes the hamiltonian of a ising system. The first part of the program works, and i obtain the matrix that i want, but a problem occurs when i try to get the eigenvalues of this complex*16 matrix by using the…
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Incorrect answer using sgeev compared to matlab

I was wondering if anyone has any experience using sgeev to compute e-vale/e-vecs in fortran. I am currently having an issue diagonalising a matrix and am not sure why. the matrix is 1 2 4 4 22 -3 22 3 3 8 -3 -22 -2 14 …
weddle_32
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Weird segmentation faults with gemm (LAPACK)

I use LAPACK and BLAS to make matrix computations. I cannot perform a gemm with certain matrices and get segmentation faults that i can't fix. For example, i can multiply two 4500x4500 matrices together but I get a segmentation fault when i try to…
thomidani
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Solving ill-conditioned system of linear equations with Lapack&co

I have the following 11x11 linear system of equations Ax = b with: A = { {1.0000000000000000, 8.0000000000000000, 6.0000000000000000, 12.0000000000000000, 24.0000000000000000, 24.0000000000000000, 8.0000000000000000, 6.0000000000000000,…
user1584773
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C algorithm to invert 1024x1024 matrix?

this is my firs question on this website. I am (desperately) trying to invert a big matrix in my program. I would like to use lapack in order to do this, and I found this thread which looks quite promising, but I think it's in C++ language. Could…
Davide
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