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Gilles commented on MATH-602: ----------------------------- Committed in revision 1157345. However it would be nice to have a non-trivial test, showing the usefulness of the method. IIUC, the rationale for adding it is that {code} getInverseConditionNumber() {code} is not always equal to {code} 1 / getConditionNumber() {code} (?) Which is rather not obvious from the code... > Inverse condition number > ------------------------ > > Key: MATH-602 > URL: https://issues.apache.org/jira/browse/MATH-602 > Project: Commons Math > Issue Type: Improvement > Affects Versions: 2.2 > Environment: All > Reporter: greg sterijevski > Priority: Minor > Labels: Condition, Inverse, Number > Fix For: 3.0 > > Attachments: svdinvcond, tstsvd > > Original Estimate: 1h > Remaining Estimate: 1h > > In SingularValueDecompositionImpl, the condition number is given as the ratio > of the largest singular value to the smallest singular value. While this is > the correct calculation, because of concerns over rank deficiency, > researchers have traditionally used the inverse of the condition number as a > more stable indicator of rank deficiency. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira