--- rpl/lapack/lapack/dpoequb.f 2011/11/21 22:19:38 1.6
+++ rpl/lapack/lapack/dpoequb.f 2017/06/17 11:06:31 1.12
@@ -2,24 +2,24 @@
*
* =========== DOCUMENTATION ===========
*
-* Online html documentation available at
-* http://www.netlib.org/lapack/explore-html/
+* Online html documentation available at
+* http://www.netlib.org/lapack/explore-html/
*
*> \htmlonly
-*> Download DPOEQUB + dependencies
-*>
-*> [TGZ]
-*>
-*> [ZIP]
-*>
+*> Download DPOEQUB + dependencies
+*>
+*> [TGZ]
+*>
+*> [ZIP]
+*>
*> [TXT]
-*> \endhtmlonly
+*> \endhtmlonly
*
* Definition:
* ===========
*
* SUBROUTINE DPOEQUB( N, A, LDA, S, SCOND, AMAX, INFO )
-*
+*
* .. Scalar Arguments ..
* INTEGER INFO, LDA, N
* DOUBLE PRECISION AMAX, SCOND
@@ -27,14 +27,14 @@
* .. Array Arguments ..
* DOUBLE PRECISION A( LDA, * ), S( * )
* ..
-*
+*
*
*> \par Purpose:
* =============
*>
*> \verbatim
*>
-*> DPOEQU computes row and column scalings intended to equilibrate a
+*> DPOEQUB computes row and column scalings intended to equilibrate a
*> symmetric positive definite matrix A and reduce its condition number
*> (with respect to the two-norm). S contains the scale factors,
*> S(i) = 1/sqrt(A(i,i)), chosen so that the scaled matrix B with
@@ -42,6 +42,12 @@
*> choice of S puts the condition number of B within a factor N of the
*> smallest possible condition number over all possible diagonal
*> scalings.
+*>
+*> This routine differs from DPOEQU by restricting the scaling factors
+*> to a power of the radix. Barring over- and underflow, scaling by
+*> these factors introduces no additional rounding errors. However, the
+*> scaled diagonal entries are no longer approximately 1 but lie
+*> between sqrt(radix) and 1/sqrt(radix).
*> \endverbatim
*
* Arguments:
@@ -100,22 +106,22 @@
* Authors:
* ========
*
-*> \author Univ. of Tennessee
-*> \author Univ. of California Berkeley
-*> \author Univ. of Colorado Denver
-*> \author NAG Ltd.
+*> \author Univ. of Tennessee
+*> \author Univ. of California Berkeley
+*> \author Univ. of Colorado Denver
+*> \author NAG Ltd.
*
-*> \date November 2011
+*> \date December 2016
*
*> \ingroup doublePOcomputational
*
* =====================================================================
SUBROUTINE DPOEQUB( N, A, LDA, S, SCOND, AMAX, INFO )
*
-* -- LAPACK computational routine (version 3.4.0) --
+* -- LAPACK computational routine (version 3.7.0) --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
-* November 2011
+* December 2016
*
* .. Scalar Arguments ..
INTEGER INFO, LDA, N