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Questions tagged [blas]

The Basic Linear Algebra Subprograms are a standard set of interfaces for low-level vector and matrix operations commonly used in scientific computing.

A reference implementation is available at NetLib; optimized implementations are also available for all high-performance computing architectures, for example:

The BLAS routines are divided into three levels:

  • Level 1: vector operations e.g. vector addition, dot product
  • Level 2: matrix-vector operations e.g. matrix-vector multiplication
  • Level 3: matrix-matrix operations e.g. matrix multiplication
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Impact of matrix sparsity on cblas sgemm in Ubuntu 14.04

I have recently discovered that the performance of a cblas_sgemm call for matrix multiplication dramatically improves if the matrices have a "large" number of zeros in them. It improves to the point that it beats its cublas cousin by around 100…
malang
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why I am getting this result in last half of array?

Can anyone tell me why the output ( Anew ) is: Anew = 0.000000 Anew = 2.000000 Anew = 4.000000 Anew = 6.000000 Anew = 16.000000 Anew = 20.000000 Anew = 24.000000 Anew = 28.000000 and not : Anew = 0.000000 Anew =…
George
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BLAS sdot_ function returns unexpected result

I'm trying to generate dot product of two matrices using the below compiling command in Linux-GCC: gcc -L/usr/lib64/atlas -lblas code.c and here is the code which seems to have compiled without an error: #include < stdio.h> int main() { int…
user3912230
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CUDA Library for Computing Kronecker Product

I have an application that requires me to calculate some large Kronecker products of 2D matrices and multiply the result by large 2D matrices. I would like to implement this on a GPU in CUDA and would prefer to use a tuned library implementation…
Michael Puglia
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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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