ChopBLAS - A Matlab library for mixed-precision and stochastically rounded linear algebra

ChopBLAS is a MATLAB library that implements the functions contained inside the BLAS (Basic Linear Algebra Subsystem) specification with each operation rounded using the chop MATLAB library. This allows for the easy simulation of linear algebra operations/algorithms in low precision floating-point and with stochastic rounding.

BLAS Functions

Level 1

Function	Operation	Description
chscal	$x_{out} = \alpha x$	Scale all entries of the vector $x$ by $\alpha$
chaxpy	$x_{out} = \alpha x + y$	Add the scaled vector $x$ to the vector $y$
chdot	$x_{out} = x'y$	Compute the dot product between $x$ and $y$
chnrm2	$x_{out} = \lVert x \rVert_{2}$	Compute the 2-norm of the vector $x$
chasum	$x_{out} = \sum_{i} \lvert x_{i} \rvert$	Compute the sum of the absolute value of the elements of the vector $x$

Level 2

Function	Operation	Description
chgemv	$x_{out} = \alpha A x + \beta y$ or $x_{out} = \alpha A' x + \beta y$	Compute the matrix-vector product $Ax + y$
chtrmv	$x_{out} = A x$ or $x_{out} = A' x$	Compute the matrix-vector product $Ax$ when $A$ is a triangular matrix
chtrsv	Find $x$ in $A x = b$ or $A' x = b$	Compute the solution to the triangular system of equations given by $A$ and $b$ when $A$ is a triangular matrix
chger	$X = \alpha x y^{T} + A$	Compute the rank-1 update of $A$ using the outer product between $x$ and $y$

License

This library is licensed under the BSD 2-Clause license, provided inside the LICENSE file in this repository.