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-rw-r--r--SRC/claqr3.f18
1 files changed, 13 insertions, 5 deletions
diff --git a/SRC/claqr3.f b/SRC/claqr3.f
index 52ab9398..9412bbd6 100644
--- a/SRC/claqr3.f
+++ b/SRC/claqr3.f
@@ -16,10 +16,12 @@
$ WORK( * ), WV( LDWV, * ), Z( LDZ, * )
* ..
*
-* ******************************************************************
+* Purpose
+* =======
+*
* Aggressive early deflation:
*
-* This subroutine accepts as input an upper Hessenberg matrix
+* CLAQR3 accepts as input an upper Hessenberg matrix
* H and performs an unitary similarity transformation
* designed to detect and deflate fully converged eigenvalues from
* a trailing principal submatrix. On output H has been over-
@@ -28,7 +30,9 @@
* hoped that the final version of H has many zero subdiagonal
* entries.
*
-* ******************************************************************
+* Arguments
+* =========
+*
* WANTT (input) LOGICAL
* If .TRUE., then the Hessenberg matrix H is fully updated
* so that the triangular Schur factor may be
@@ -73,6 +77,7 @@
* subroutine. N .LE. LDH
*
* ILOZ (input) INTEGER
+*
* IHIZ (input) INTEGER
* Specify the rows of Z to which transformations must be
* applied if WANTZ is .TRUE.. 1 .LE. ILOZ .LE. IHIZ .LE. N.
@@ -143,12 +148,15 @@
* in WORK(1). No error message related to LWORK is issued
* by XERBLA. Neither H nor Z are accessed.
*
-* ================================================================
+* Further Details
+* ===============
+*
* Based on contributions by
* Karen Braman and Ralph Byers, Department of Mathematics,
* University of Kansas, USA
*
-* ================================================================
+* ================================================================
+*
* .. Parameters ..
COMPLEX ZERO, ONE
PARAMETER ( ZERO = ( 0.0e0, 0.0e0 ),