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CONDEX: Counter examples to the LINPACK condition number estimator

from the MMDELI

Matrix Generator CONDEX
Source: A.K. Cline and R.K. Rew
Discipline: numerical linear algebra
Language: Java applet
Output format: Matrix Market format

This is a Java applet which generates matrices from three ill-conditioned classes. These were posed by Cline and Rew as counter-examples to the condition number estimator used in the LINPACK package. Examples B and C are nearly diagonal, whereas example D is lower triangular matrix with 1s on the diagonal (except the last which is -1) and -1s on the off-diagonals.

This generator was developed by Bruce Miller of NIST based on Nick Higham's Test Matrix Toolbox for MATLAB.

Parameters:

EXAMPLEselects one of three examples
Norder of the matrix
THETAa linear contribution to elements in Examples B and C

Links:


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Last change in this page: Wed Sep 22 13:34:19 US/Eastern 2004 [Comments: ]