Next: Unit Triangular Matrices Up: Matrix Storage Schemes Previous: Band Storage Contents Index

##
Tridiagonal and Bidiagonal Matrices

An unsymmetric tridiagonal matrix of order n is stored in three one-dimensional arrays, one of length n containing the diagonal elements, and two of length n-1 containing the subdiagonal and superdiagonal elements in elements 1:n-1.

A symmetric tridiagonal or bidiagonal matrix is stored in two one-dimensional arrays, one of length n containing the diagonal elements, and one of length n-1 containing the off-diagonal elements. (EISPACK routines store the off-diagonal elements in elements 2:n of a vector of length n.)