**r83**,
a C code which
carries out some basic linear algebra operations on R83 matrices
(real 64 bit precision tridiagonal 3xN format).

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

**r83** is available in
a C version and
a C++ version and
a FORTRAN90 version and
a MATLAB version and
a Python version.

R83_NP, a C code which contains linear algebra routines for R83_NP matrices (real, 64 bit, tridiagonal 3xN format, nonpivoting factorization).

R83P, a C code which contains linear algebra routines for R83P matrices (real, 64 bit, tridiagonal periodic format).

R83S, a C code which contains linear algebra routines for R83S matrices (real, 64 bit, tridiagonal scalar format).

R83T, a C code which contains linear algebra routines for R83T matrices (real, 64 bit, tridiagonal Mx3 format).

R83V, a C code which contains linear algebra routines for R83V matrices (real, 64 bit, tridiagonal three vector format).

R85, a C code which contains linear algebra routines for R85 matrices (real, 64 bit, pentadiagonal format).

R8BB, a C code which contains linear algebra routines for R8BB matrices (real, 64 bit, border banded format).

R8BLT, a C code which contains linear algebra routines for R8BLT matrices (real, 64 bit, band lower triangular format).

R8BTO, a C code which contains linear algebra routines for R8BTO matrices (real, 64 bit, block Toeplitz format).

R8BUT, a C code which contains linear algebra routines for R8BUT matrices (real, 64 bit, band upper triangular format).

R8CB, a C code which contains linear algebra routines for R8CB matrices (real, 64 bit, Compressed Band format).

R8CBB, a C code which contains linear algebra routines for R8CBB matrices (real, 64 bit, Compressed Border Banded format).

R8CC, a C code which contains linear algebra routines for R8CC matrices (real, 64 bit, Compressed Column (Colptr,Row,Value) format).

R8CI, a C code which contains linear algebra routines for R8CI matrices (real, 64 bit, circulant format).

R8COL, a C code which contains utility routines for R8COL's, that is, double precision real MxN arrays, considered as N column vectors, each of length M. The data may be thought of as a matrix of multiple columns, and many operations will be carried out columnwise.

R8GB, a C code which contains linear algebra routines for R8GB matrices (real, 64 bit, General Banded format).

R8GD, a C code which contains linear algebra routines for R8GD matrices (real, 64 bit, general diagonal format).

R8GE, a C code which contains linear algebra routines for R8GE matrices (real, 64 bit, General format).

R8GE_NP, a C code which contains nonpivoting linear algebra routines for R8GE_NP matrices (real, 64 bit, General Nonpivoting format).

R8LT, a C code which contains linear algebra routines for R8LT matrices (real, 64 bit, lower triangular format).

R8LTT, a C code which contains linear algebra routines for R8LTT matrices (real, 64 bit, lower triangular Toeplitz format).

R8NCF, a C code which contains linear algebra routines for R8NCF matrices (real, 64 bit, nonsymmetric coordinate format).

R8PBL, a C code which contains linear algebra routines for R8PBL matrices (real, 64 bit, positive definite symmetric band lower format).

R8PBU, a C code which contains linear algebra routines for R8PBU matrices (real, 64 bit, positive definite symmetric band upper format).

R8PO, a C code which contains linear algebra routines for R8PO matrices (real, 64 bit, positive definite symmetric format).

R8PP, a C code which contains linear algebra routines for R8PP matrices (real, 64 bit, positive definite symmetric packed format).

R8RI, a C code which contains linear algebra routines for R8RI matrices (real, 64 bit, row indexed format).

R8ROW, a C code which contains utility routines for R8ROW's, that is, double precision real MxN arrays, considered as M row vectors, each of length N. The data may be thought of as a matrix of multiple rows, and many operations will be carried out rowwise.

R8S3, a C code which contains linear algebra routines for R8S3 matrices (real, 64 bit, SLAP Triad (I,J,AIJ) format).

R8SD, a C code which contains linear algebra routines for R8SD matrices (real, 64 bit, symmetric diagonal format).

R8SM, a C code which contains linear algebra routines for R8SM (Sherman-Morrison) matrices (real, 64 bit, A-u*v' format).

R8SP, a C code which contains linear algebra routines for R8SP matrices (real, 64 bit, SLAP Triad (I,J,AIJ) format).

R8SR, a C code which carries out linear algebra operations for R8SR matrices (real, 64 bit, diagonal + compressed row offdiagonal format).

R8SS, a C code which carries out linear algebra operations for R8SS matrices (real, 64 bit, symmetric skyline format).

R8STO, a C code which contains linear algebra routines for R8STO matrices (real, 64 bit, symmetric Toeplitz N format).

R8TO, a C code which contains linear algebra routines for R8TO matrices (real, 64 bit, Toeplitz 2*N-1 format).

R8UT, a C code which contains linear algebra routines for R8UT matrices (real, 64 bit, upper triangular format).

R8UTT, a C code which contains linear algebra routines for R8UTT matrices (real, 64 bit, upper triangular Toeplitz format).

R8VM, a C code which contains linear algebra routines for R8VM matrices (real, 64 bit, Vandermonde format).