diff options
Diffstat (limited to 'SRC/zheevr.f')
| -rw-r--r-- | SRC/zheevr.f | 21 |
1 files changed, 7 insertions, 14 deletions
diff --git a/SRC/zheevr.f b/SRC/zheevr.f index 980d22d8..c59f26c0 100644 --- a/SRC/zheevr.f +++ b/SRC/zheevr.f @@ -187,22 +187,18 @@ *> An approximate eigenvalue is accepted as converged *> when it is determined to lie in an interval [a,b] *> of width less than or equal to -*> \endverbatim -*> \verbatim +*> *> ABSTOL + EPS * max( |a|,|b| ) , -*> \endverbatim -*> \verbatim +*> *> where EPS is the machine precision. If ABSTOL is less than *> or equal to zero, then EPS*|T| will be used in its place, *> where |T| is the 1-norm of the tridiagonal matrix obtained *> by reducing A to tridiagonal form. -*> \endverbatim -*> \verbatim +*> *> See "Computing Small Singular Values of Bidiagonal Matrices *> with Guaranteed High Relative Accuracy," by Demmel and *> Kahan, LAPACK Working Note #3. -*> \endverbatim -*> \verbatim +*> *> If high relative accuracy is important, set ABSTOL to *> DLAMCH( 'Safe minimum' ). Doing so will guarantee that *> eigenvalues are computed to high relative accuracy when @@ -272,8 +268,7 @@ *> For optimal efficiency, LWORK >= (NB+1)*N, *> where NB is the max of the blocksize for ZHETRD and for *> ZUNMTR as returned by ILAENV. -*> \endverbatim -*> \verbatim +*> *> If LWORK = -1, then a workspace query is assumed; the routine *> only calculates the optimal sizes of the WORK, RWORK and *> IWORK arrays, returns these values as the first entries of @@ -292,8 +287,7 @@ *> \verbatim *> LRWORK is INTEGER *> The length of the array RWORK. LRWORK >= max(1,24*N). -*> \endverbatim -*> \verbatim +*> *> If LRWORK = -1, then a workspace query is assumed; the *> routine only calculates the optimal sizes of the WORK, RWORK *> and IWORK arrays, returns these values as the first entries @@ -312,8 +306,7 @@ *> \verbatim *> LIWORK is INTEGER *> The dimension of the array IWORK. LIWORK >= max(1,10*N). -*> \endverbatim -*> \verbatim +*> *> If LIWORK = -1, then a workspace query is assumed; the *> routine only calculates the optimal sizes of the WORK, RWORK *> and IWORK arrays, returns these values as the first entries |