c = condest(A)
[c,v] = condest(A)
[c,v] = condest(A,trace)
c = condest(A)
uses Higham's modification of Hager's method to estimate the condition number of a matrix. The computed c
is a lower bound for the condition of A
in the 1-norm.
[c,v] = condest(A)
also computes a vector v
such that
Thus, v
is an approximate null vector of A
if c
is large.
[c,v] = condest(A,trace)
provides further information about the estimate, where trace can be:
rcond
. trace = -1
) for sparse matrices.
cond
,normest
,rcond
(c) Copyright 1994 by The MathWorks, Inc.