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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.


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


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