functionrcond
Return the reciprocal condition number of a matrix
Extends from Modelica.Icons.Function (Icon for functions).
Information
Syntax
r = Matrices.rcond(A);
Description
This function estimates the reciprocal of the condition number (norm(A) * norm(inv(A))) of a general real matrix A, in either the 1-norm or the infinity-norm, using the LAPACK function DGECON. If rcond(A) is near 1.0, A is well conditioned and A is ill conditioned if rcond(A) is near zero.
Example
A = [1, 2;
2, 1];
r = rcond(A);
results in:
r = 0.3333
See also
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real[:,size(A, 1)] | A | Square real matrix | |
| Boolean | inf | false | Is true if infinity norm is used and false for 1-norm |
Outputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real | rcond | Reciprocal condition number of A | |
| Integer | info | Information |
Revisions
- 2010/05/31 by Marcus Baur, DLR-RM