Mercurial > matrix-functions
view toolbox/moler.m @ 8:a587712dcf5f draft default tip
funm_atom.m: rename fun_atom to funm_atom
* funm_atom.m: rename fun_atom to funm_atom.
author | Antonio Pino Robles <data.script93@gmail.com> |
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date | Fri, 29 May 2015 09:48:36 +0200 |
parents | 8f23314345f4 |
children |
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function A = moler(n, alpha) %MOLER Moler matrix - symmetric positive definite. % A = MOLER(N, ALPHA) is the symmetric positive definite N-by-N matrix % U'*U where U = TRIW(N, ALPHA). % For ALPHA = -1 (the default) A(i,j) = MIN(i,j)-2, A(i,i) = i. % A has one small eigenvalue. % Nash (1990) attributes the ALPHA = -1 matrix to Moler. % % Reference: % J.C. Nash, Compact Numerical Methods for Computers: Linear % Algebra and Function Minimisation, second edition, Adam Hilger, % Bristol, 1990 (Appendix 1). if nargin == 1, alpha = -1; end A = triw(n, alpha)'*triw(n, alpha);