These codes were written in connection with the Ph.D. thesis Sabine Van Huffel, 1987, Katholieke Universiteit Leuven. A revised and expanded version of the thesis is in SIAM Frotiers book series. This particular version was received on 21 March 1988. The primary routines to be called by the user are dtls, psvd, and ptls. A complete list is: bidiag auxiliary routines called by dtls, psvd, ptls dtls solves Ax=b, where A as well as b may be inaccurate estim singular values of a bidiagonal by bisection nsingv number of singular values left of a bound, of a bidiagonal matrix psvd basis for the left/right space corresponding to small singular values ptls like dtls, but using the faster Partial SVD qrql diagonalizes a bidiagonal matrix For each name x in this list, there is a file x.f containing a Fortran subroutine and a file x-doc containing documentaion. Some of the documentation files also contain sample driver programs. By default, when asking for a top-level routine like dtls you will also get any necessary auxiliary routines. In keeping with netlib policy, routines from linpack and the blas have been omitted here since they are available directly. To include them in your return mail, say send dtls from vanhuffel linpack blas. send dtls-doc from vanhuffel