SPM_matrix_times_vector_Version

version for the matrix-times-vector operations for sparse linear systems

version 1: -> automatically switch to version 2 version 2: classical loop over all matrix lines: do i = 1,nMatrixLines) version 3: vectorize the loop over all matrix lines: do i = 1,nMatrixLines,i4 :: MxV(i:i+i4-1) = sum{ (MMM(i:i+i4-1,.) * X(.) } assuming that the intrinsic sum() function of INTEL-fortran is also perfectly vectorized.
SPM_matrix_times_vector_Version = 3 # supposed to be faster as vectorizing some loops
Default: SPM_matrix_times_vector_Version = 1
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SPM_matrix_times_vector_Version version for the matrix-times-vector operations for sparse linear systems