diff options
| author | julie <julielangou@users.noreply.github.com> | 2011-11-01 22:02:31 +0000 |
|---|---|---|
| committer | julie <julielangou@users.noreply.github.com> | 2011-11-01 22:02:31 +0000 |
| commit | d5c30c90bdecf38da1064e2ed52583634573e741 (patch) | |
| tree | 480fc5ff31ee14b83116b6428aad79ea6e89362d /SRC/chbgvx.f | |
| parent | 04670a68760fa27333f8bcef8172f71adc6880ef (diff) | |
Never say never...
Diffstat (limited to 'SRC/chbgvx.f')
| -rw-r--r-- | SRC/chbgvx.f | 21 |
1 files changed, 7 insertions, 14 deletions
diff --git a/SRC/chbgvx.f b/SRC/chbgvx.f index fb40c44f..451ffc35 100644 --- a/SRC/chbgvx.f +++ b/SRC/chbgvx.f @@ -105,8 +105,7 @@ *> as follows: *> if UPLO = 'U', AB(ka+1+i-j,j) = A(i,j) for max(1,j-ka)<=i<=j; *> if UPLO = 'L', AB(1+i-j,j) = A(i,j) for j<=i<=min(n,j+ka). -*> \endverbatim -*> \verbatim +*> *> On exit, the contents of AB are destroyed. *> \endverbatim *> @@ -125,8 +124,7 @@ *> as follows: *> if UPLO = 'U', BB(kb+1+i-j,j) = B(i,j) for max(1,j-kb)<=i<=j; *> if UPLO = 'L', BB(1+i-j,j) = B(i,j) for j<=i<=min(n,j+kb). -*> \endverbatim -*> \verbatim +*> *> On exit, the factor S from the split Cholesky factorization *> B = S**H*S, as returned by CPBSTF. *> \endverbatim @@ -161,8 +159,7 @@ *> \param[in] VU *> \verbatim *> VU is REAL -*> \endverbatim -*> \verbatim +*> *> If RANGE='V', the lower and upper bounds of the interval to *> be searched for eigenvalues. VL < VU. *> Not referenced if RANGE = 'A' or 'I'. @@ -176,8 +173,7 @@ *> \param[in] IU *> \verbatim *> IU is INTEGER -*> \endverbatim -*> \verbatim +*> *> If RANGE='I', the indices (in ascending order) of the *> smallest and largest eigenvalues to be returned. *> 1 <= IL <= IU <= N, if N > 0; IL = 1 and IU = 0 if N = 0. @@ -191,17 +187,14 @@ *> 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 AP to tridiagonal form. -*> \endverbatim -*> \verbatim +*> *> Eigenvalues will be computed most accurately when ABSTOL is *> set to twice the underflow threshold 2*SLAMCH('S'), not zero. *> If this routine returns with INFO>0, indicating that some |