matrices

Mattrices

These implementations of the matrix-matrix multiplications in various languages are intended to illustrate some bad practices and their performance impact.

What is it?

1. pure_python_matmul.py: matrix multiplication based on a representation as list of lists, very slow, do not ever do this
2. numpy_matmul.py: numpy.dot function used to multiply numpy matrices, performance depends on quality of underlying BLAS library, but at any rate orders of magnitude faster than naive implementation
3. pure_fortran_matmul.f90: Fortran implementation using the matmul initrinsic function
4. blas_fortran.f90: Fortran implementation using the DGEMM BLAS level 3 procedure
5. pure_c_matmul.c: naive C implementation

A make file is provided to build the Fortran and C implementations.