Use normwise criterion for inf eigenvalues in QZ

chrwarm · Aug 8, 2022 · c699406 · c699406
1 parent 3381a0e
commit c699406
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Showing 4 changed files with 8 additions and 28 deletions.
diff --git a/SRC/chgeqz.f b/SRC/chgeqz.f
@@ -523,9 +523,7 @@ SUBROUTINE CHGEQZ( JOB, COMPQ, COMPZ, N, ILO, IHI, H, LDH, T, LDT,
             END IF
          END IF
 *
-         IF( ABS( T( ILAST, ILAST ) ).LE.MAX( SAFMIN, ULP*( 
-     $         ABS( T( ILAST - 1, ILAST ) ) + ABS( T( ILAST-1, ILAST-1 )
-     $          ) ) ) ) THEN
+         IF( ABS( T( ILAST, ILAST ) ).LE.BTOL ) THEN
             T( ILAST, ILAST ) = CZERO
             GO TO 50
          END IF
@@ -551,10 +549,7 @@ SUBROUTINE CHGEQZ( JOB, COMPQ, COMPZ, N, ILO, IHI, H, LDH, T, LDT,
 *
 *           Test 2: for T(j,j)=0
 *
-            TEMP = ABS ( T( J, J + 1 ) )
-            IF ( J .GT. ILO )
-     $           TEMP = TEMP + ABS ( T( J - 1, J ) )
-            IF( ABS( T( J, J ) ).LT.MAX( SAFMIN,ULP*TEMP ) ) THEN
+            IF( ABS( T( J, J ) ).LT.BTOL ) THEN
                T( J, J ) = CZERO
 *
 *              Test 1a: Check for 2 consecutive small subdiagonals in A

diff --git a/SRC/dhgeqz.f b/SRC/dhgeqz.f
@@ -536,9 +536,7 @@ SUBROUTINE DHGEQZ( JOB, COMPQ, COMPZ, N, ILO, IHI, H, LDH, T, LDT,
             END IF
          END IF
 *
-         IF( ABS( T( ILAST, ILAST ) ).LE.MAX( SAFMIN, ULP*( 
-     $         ABS( T( ILAST - 1, ILAST ) ) + ABS( T( ILAST-1, ILAST-1 )
-     $          ) ) ) ) THEN
+         IF( ABS( T( ILAST, ILAST ) ).LE.BTOL ) THEN
             T( ILAST, ILAST ) = ZERO
             GO TO 70
          END IF
@@ -564,10 +562,7 @@ SUBROUTINE DHGEQZ( JOB, COMPQ, COMPZ, N, ILO, IHI, H, LDH, T, LDT,
 *
 *           Test 2: for T(j,j)=0
 *
-            TEMP = ABS ( T( J, J + 1 ) )
-            IF ( J .GT. ILO )
-     $           TEMP = TEMP + ABS ( T( J - 1, J ) )
-            IF( ABS( T( J, J ) ).LT.MAX( SAFMIN,ULP*TEMP ) ) THEN
+            IF( ABS( T( J, J ) ).LT.BTOL ) THEN
                T( J, J ) = ZERO
 *
 *              Test 1a: Check for 2 consecutive small subdiagonals in A

diff --git a/SRC/shgeqz.f b/SRC/shgeqz.f
@@ -536,9 +536,7 @@ SUBROUTINE SHGEQZ( JOB, COMPQ, COMPZ, N, ILO, IHI, H, LDH, T, LDT,
             END IF
          END IF
 *
-         IF( ABS( T( ILAST, ILAST ) ).LE.MAX( SAFMIN, ULP*( 
-     $         ABS( T( ILAST - 1, ILAST ) ) + ABS( T( ILAST-1, ILAST-1 )
-     $          ) ) ) ) THEN
+         IF( ABS( T( ILAST, ILAST ) ).LE.BTOL ) THEN
             T( ILAST, ILAST ) = ZERO
             GO TO 70
          END IF
@@ -564,10 +562,7 @@ SUBROUTINE SHGEQZ( JOB, COMPQ, COMPZ, N, ILO, IHI, H, LDH, T, LDT,
 *
 *           Test 2: for T(j,j)=0
 *
-            TEMP = ABS ( T( J, J + 1 ) )
-            IF ( J .GT. ILO )
-     $           TEMP = TEMP + ABS ( T( J - 1, J ) )
-            IF( ABS( T( J, J ) ).LT.MAX( SAFMIN,ULP*TEMP ) ) THEN
+            IF( ABS( T( J, J ) ).LT.BTOL ) THEN
                T( J, J ) = ZERO
 *
 *              Test 1a: Check for 2 consecutive small subdiagonals in A

diff --git a/SRC/zhgeqz.f b/SRC/zhgeqz.f
@@ -524,9 +524,7 @@ SUBROUTINE ZHGEQZ( JOB, COMPQ, COMPZ, N, ILO, IHI, H, LDH, T, LDT,
             END IF
          END IF
 *
-         IF( ABS( T( ILAST, ILAST ) ).LE.MAX( SAFMIN, ULP*( 
-     $         ABS( T( ILAST - 1, ILAST ) ) + ABS( T( ILAST-1, ILAST-1 )
-     $          ) ) ) ) THEN
+         IF( ABS( T( ILAST, ILAST ) ).LE.BTOL ) THEN
             T( ILAST, ILAST ) = CZERO
             GO TO 50
          END IF
@@ -552,10 +550,7 @@ SUBROUTINE ZHGEQZ( JOB, COMPQ, COMPZ, N, ILO, IHI, H, LDH, T, LDT,
 *
 *           Test 2: for T(j,j)=0
 *
-            TEMP = ABS ( T( J, J + 1 ) )
-            IF ( J .GT. ILO )
-     $           TEMP = TEMP + ABS ( T( J - 1, J ) )
-            IF( ABS( T( J, J ) ).LT.MAX( SAFMIN,ULP*TEMP ) ) THEN
+            IF( ABS( T( J, J ) ).LT.BTOL ) THEN
                T( J, J ) = CZERO
 *
 *              Test 1a: Check for 2 consecutive small subdiagonals in A