f07pjf computes the inverse of a real symmetric indefinite matrix
, where
has been factorized by
f07pdf, using packed storage.
f07pjf is used to compute the inverse of a real symmetric indefinite matrix
, the routine must be preceded by a call to
f07pdf, which computes the Bunch–Kaufman factorization of
, using packed storage.
The computed inverse
satisfies a bound of the form
- if , ;
- if , ,
is a modest linear function of
, and
is the
machine precision.
Background information to multithreading can be found in the
Multithreading documentation.
Please consult the
X06 Chapter Introduction for information on how to control and interrogate the OpenMP environment used within this routine. Please also consult the
Users' Note for your implementation for any additional implementation-specific information.
The complex analogues of this routine are
f07pwf for Hermitian matrices and
f07qwf for symmetric matrices.
This example computes the inverse of the matrix
, where
Here
is symmetric indefinite, stored in packed form, and must first be factorized by
f07pdf.