Correction reported by Elena (Oracle)

LAPACK 3.5.0 [cz]hgeqz.f compute eigenvalues differently depending on whether
eigenvectors are requested or not. Since the computation is different, eigenvalues
are not bit-by-bit identical whether eigenvectors are requested or not.

This fix enables to have [cz]hgeqz.f behaving more of the same whether eigenvectors
are requested or not.

Note: The fact that eigenvalues are bit-by-bit identical whether eigenvectors are
requested or not is checked in the LAPACK test suite.

diff --git a/SRC/chgeqz.f b/SRC/chgeqz.f
index 3209c2c..7d2e810 100644 (file)
--- a/SRC/chgeqz.f
+++ b/SRC/chgeqz.f
@@ -453,7 +453,7 @@
                CALL CSCAL( J-1, SIGNBC, T( 1, J ), 1 )
                CALL CSCAL( J, SIGNBC, H( 1, J ), 1 )
             ELSE
-               H( J, J ) = H( J, J )*SIGNBC
+               CALL CSCAL( 1, SIGNBC, H( J, J ), 1 )
             END IF
             IF( ILZ )
      $         CALL CSCAL( N, SIGNBC, Z( 1, J ), 1 )
@@ -665,7 +665,7 @@
                CALL CSCAL( ILAST+1-IFRSTM, SIGNBC, H( IFRSTM, ILAST ),
      $                     1 )
             ELSE
-               H( ILAST, ILAST ) = H( ILAST, ILAST )*SIGNBC
+               CALL CSCAL( ILAST, SIGNBC, H( ILAST, ILAST ), 1 )
             END IF
             IF( ILZ )
      $         CALL CSCAL( N, SIGNBC, Z( 1, ILAST ), 1 )
@@ -849,7 +849,7 @@
                CALL CSCAL( J-1, SIGNBC, T( 1, J ), 1 )
                CALL CSCAL( J, SIGNBC, H( 1, J ), 1 )
             ELSE
-               H( J, J ) = H( J, J )*SIGNBC
+               CALL CSCAL( 1, SIGNBC, H( J, J ), 1 )
             END IF
             IF( ILZ )
      $         CALL CSCAL( N, SIGNBC, Z( 1, J ), 1 )

diff --git a/SRC/zhgeqz.f b/SRC/zhgeqz.f
index 3f28131..3df6754 100644 (file)
--- a/SRC/zhgeqz.f
+++ b/SRC/zhgeqz.f
@@ -454,7 +454,7 @@
                CALL ZSCAL( J-1, SIGNBC, T( 1, J ), 1 )
                CALL ZSCAL( J, SIGNBC, H( 1, J ), 1 )
             ELSE
-               H( J, J ) = H( J, J )*SIGNBC
+               CALL ZSCAL( 1, SIGNBC, H( J, J ), 1 )
             END IF
             IF( ILZ )
      $         CALL ZSCAL( N, SIGNBC, Z( 1, J ), 1 )
@@ -666,7 +666,7 @@
                CALL ZSCAL( ILAST+1-IFRSTM, SIGNBC, H( IFRSTM, ILAST ),
      $                     1 )
             ELSE
-               H( ILAST, ILAST ) = H( ILAST, ILAST )*SIGNBC
+               CALL ZSCAL( ILAST, SIGNBC, H( ILAST, ILAST ), 1 )
             END IF
             IF( ILZ )
      $         CALL ZSCAL( N, SIGNBC, Z( 1, ILAST ), 1 )
@@ -850,7 +850,7 @@
                CALL ZSCAL( J-1, SIGNBC, T( 1, J ), 1 )
                CALL ZSCAL( J, SIGNBC, H( 1, J ), 1 )
             ELSE
-               H( J, J ) = H( J, J )*SIGNBC
+               CALL ZSCAL( 1, SIGNBC, H( J, J ), 1 )
             END IF
             IF( ILZ )
      $         CALL ZSCAL( N, SIGNBC, Z( 1, J ), 1 )