Algorithm 741: least-squares solution of a linear, bordered, block-diagonal system of equations

Abstract

A package of Fortran subroutines is presented for the least-squares solution of a system of overdetermined, full-rank, linear equations with single-bordered block-diagonal structure. This structure allows for a natural sequential processing, one block diagonal at a time, so that large systems can be handled even on smaller machines. Orthogonal transformations in the form of Householder reflections are used to factor the system. The routines make heavy use of the Levels 1, 2, and 3 BLAS.