Fix internal errors getting ignored in calculation of selected eigenvalues (Reference-LAPACK PR 1204)

lapack-netlib/SRC/chbevx.f

@@ -246,8 +246,11 @@
 *>          INFO is INTEGER
 *>          = 0:  successful exit
 *>          < 0:  if INFO = -i, the i-th argument had an illegal value
-*>          > 0:  if INFO = i, then i eigenvectors failed to converge.
-*>                Their indices are stored in array IFAIL.
+*>          > 0:  if INFO = i, and i is:
+*>                <= N: then i eigenvectors failed to converge in
+*>                     CSTEIN; their indices are stored in IFAIL.
+*>                > N: SSTEBZ returned INFO = INFO - N;
+*>                     see SSTEBZ for details.
 *> \endverbatim
 *
 *  Authors:
@@ -484,12 +487,19 @@ SUBROUTINE CHBEVX( JOBZ, RANGE, UPLO, N, KD, AB, LDAB, Q, LDQ, VL,
       CALL SSTEBZ( RANGE, ORDER, N, VLL, VUU, IL, IU, ABSTLL,
      $             RWORK( INDD ), RWORK( INDE ), M, NSPLIT, W,
      $             IWORK( INDIBL ), IWORK( INDISP ), RWORK( INDRWK ),
-     $             IWORK( INDIWK ), INFO )
+     $             IWORK( INDIWK ), IINFO )
+      IF( IINFO.NE.0 ) THEN
+         INFO = N + IINFO
+         IF( IINFO.NE.1 )
+     $      GO TO 30
+      END IF
 *
       IF( WANTZ ) THEN
          CALL CSTEIN( N, RWORK( INDD ), RWORK( INDE ), M, W,
      $                IWORK( INDIBL ), IWORK( INDISP ), Z, LDZ,
-     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, INFO )
+     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, IINFO )
+         IF( IINFO.NE.0 .AND. INFO.EQ.0 )
+     $      INFO = IINFO
 *
 *        Apply unitary matrix used in reduction to tridiagonal
 *        form to eigenvectors returned by CSTEIN.

lapack-netlib/SRC/chbevx_2stage.f

@@ -273,8 +273,11 @@
 *>          INFO is INTEGER
 *>          = 0:  successful exit
 *>          < 0:  if INFO = -i, the i-th argument had an illegal value
-*>          > 0:  if INFO = i, then i eigenvectors failed to converge.
-*>                Their indices are stored in array IFAIL.
+*>          > 0:  if INFO = i, and i is:
+*>                <= N: then i eigenvectors failed to converge in
+*>                     CSTEIN; their indices are stored in IFAIL.
+*>                > N: SSTEBZ returned INFO = INFO - N;
+*>                     see SSTEBZ for details.
 *> \endverbatim
 *
 *  Authors:
@@ -577,12 +580,19 @@ SUBROUTINE CHBEVX_2STAGE( JOBZ, RANGE, UPLO, N, KD, AB, LDAB,
       CALL SSTEBZ( RANGE, ORDER, N, VLL, VUU, IL, IU, ABSTLL,
      $             RWORK( INDD ), RWORK( INDE ), M, NSPLIT, W,
      $             IWORK( INDIBL ), IWORK( INDISP ), RWORK( INDRWK ),
-     $             IWORK( INDIWK ), INFO )
+     $             IWORK( INDIWK ), IINFO )
+      IF( IINFO.NE.0 ) THEN
+         INFO = N + IINFO
+         IF( IINFO.NE.1 )
+     $      GO TO 30
+      END IF
 *
       IF( WANTZ ) THEN
          CALL CSTEIN( N, RWORK( INDD ), RWORK( INDE ), M, W,
      $                IWORK( INDIBL ), IWORK( INDISP ), Z, LDZ,
-     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, INFO )
+     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, IINFO )
+         IF( IINFO.NE.0 .AND. INFO.EQ.0 )
+     $      INFO = IINFO
 *
 *        Apply unitary matrix used in reduction to tridiagonal
 *        form to eigenvectors returned by CSTEIN.

lapack-netlib/SRC/chbgvx.f

@@ -270,12 +270,14 @@
 *>          = 0:  successful exit
 *>          < 0:  if INFO = -i, the i-th argument had an illegal value
 *>          > 0:  if INFO = i, and i is:
-*>             <= N:  then i eigenvectors failed to converge.  Their
-*>                    indices are stored in array IFAIL.
-*>             > N:   if INFO = N + i, for 1 <= i <= N, then CPBSTF
-*>                    returned INFO = i: B is not positive definite.
-*>                    The factorization of B could not be completed and
-*>                    no eigenvalues or eigenvectors were computed.
+*>             <= N:    then i eigenvectors failed to converge in
+*>                      CSTEIN; their indices are stored in IFAIL.
+*>             N+1..2N: if INFO = N + i, for 1 <= i <= N, then CPBSTF
+*>                      returned INFO = i: B is not positive definite.
+*>                      The factorization of B could not be completed
+*>                      and no eigenvalues or eigenvectors were computed.
+*>             > 2N:    if INFO = 2*N + i, then SSTEBZ returned
+*>                      INFO = i; see SSTEBZ for details.
 *> \endverbatim
 *
 *  Authors:
@@ -475,12 +477,19 @@ SUBROUTINE CHBGVX( JOBZ, RANGE, UPLO, N, KA, KB, AB, LDAB, BB,
       CALL SSTEBZ( RANGE, ORDER, N, VL, VU, IL, IU, ABSTOL,
      $             RWORK( INDD ), RWORK( INDE ), M, NSPLIT, W,
      $             IWORK( 1 ), IWORK( INDISP ), RWORK( INDRWK ),
-     $             IWORK( INDIWK ), INFO )
+     $             IWORK( INDIWK ), IINFO )
+      IF( IINFO.NE.0 ) THEN
+         INFO = 2*N + IINFO
+         IF( IINFO.NE.1 )
+     $      GO TO 30
+      END IF
 *
       IF( WANTZ ) THEN
          CALL CSTEIN( N, RWORK( INDD ), RWORK( INDE ), M, W,
      $                IWORK( 1 ), IWORK( INDISP ), Z, LDZ,
-     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, INFO )
+     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, IINFO )
+         IF( IINFO.NE.0 .AND. INFO.EQ.0 )
+     $      INFO = IINFO
 *
 *        Apply unitary matrix used in reduction to tridiagonal
 *        form to eigenvectors returned by CSTEIN.

lapack-netlib/SRC/cheevx.f

@@ -238,8 +238,11 @@
 *>          INFO is INTEGER
 *>          = 0:  successful exit
 *>          < 0:  if INFO = -i, the i-th argument had an illegal value
-*>          > 0:  if INFO = i, then i eigenvectors failed to converge.
-*>                Their indices are stored in array IFAIL.
+*>          > 0:  if INFO = i, and i is:
+*>                <= N: then i eigenvectors failed to converge in
+*>                     CSTEIN; their indices are stored in IFAIL.
+*>                > N: SSTEBZ returned INFO = INFO - N;
+*>                     see SSTEBZ for details.
 *> \endverbatim
 *
 *  Authors:
@@ -494,12 +497,19 @@ SUBROUTINE CHEEVX( JOBZ, RANGE, UPLO, N, A, LDA, VL, VU, IL, IU,
       CALL SSTEBZ( RANGE, ORDER, N, VLL, VUU, IL, IU, ABSTLL,
      $             RWORK( INDD ), RWORK( INDE ), M, NSPLIT, W,
      $             IWORK( INDIBL ), IWORK( INDISP ), RWORK( INDRWK ),
-     $             IWORK( INDIWK ), INFO )
+     $             IWORK( INDIWK ), IINFO )
+      IF( IINFO.NE.0 ) THEN
+         INFO = N + IINFO
+         IF( IINFO.NE.1 )
+     $      GO TO 40
+      END IF
 *
       IF( WANTZ ) THEN
          CALL CSTEIN( N, RWORK( INDD ), RWORK( INDE ), M, W,
      $                IWORK( INDIBL ), IWORK( INDISP ), Z, LDZ,
-     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, INFO )
+     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, IINFO )
+         IF( IINFO.NE.0 .AND. INFO.EQ.0 )
+     $      INFO = IINFO
 *
 *        Apply unitary matrix used in reduction to tridiagonal
 *        form to eigenvectors returned by CSTEIN.

lapack-netlib/SRC/cheevx_2stage.f

@@ -253,8 +253,11 @@
 *>          INFO is INTEGER
 *>          = 0:  successful exit
 *>          < 0:  if INFO = -i, the i-th argument had an illegal value
-*>          > 0:  if INFO = i, then i eigenvectors failed to converge.
-*>                Their indices are stored in array IFAIL.
+*>          > 0:  if INFO = i, and i is:
+*>                <= N: then i eigenvectors failed to converge in
+*>                     CSTEIN; their indices are stored in IFAIL.
+*>                > N: SSTEBZ returned INFO = INFO - N;
+*>                     see SSTEBZ for details.
 *> \endverbatim
 *
 *  Authors:
@@ -553,12 +556,19 @@ SUBROUTINE CHEEVX_2STAGE( JOBZ, RANGE, UPLO, N, A, LDA, VL, VU,
       CALL SSTEBZ( RANGE, ORDER, N, VLL, VUU, IL, IU, ABSTLL,
      $             RWORK( INDD ), RWORK( INDE ), M, NSPLIT, W,
      $             IWORK( INDIBL ), IWORK( INDISP ), RWORK( INDRWK ),
-     $             IWORK( INDIWK ), INFO )
+     $             IWORK( INDIWK ), IINFO )
+      IF( IINFO.NE.0 ) THEN
+         INFO = N + IINFO
+         IF( IINFO.NE.1 )
+     $      GO TO 40
+      END IF
 *
       IF( WANTZ ) THEN
          CALL CSTEIN( N, RWORK( INDD ), RWORK( INDE ), M, W,
      $                IWORK( INDIBL ), IWORK( INDISP ), Z, LDZ,
-     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, INFO )
+     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, IINFO )
+         IF( IINFO.NE.0 .AND. INFO.EQ.0 )
+     $      INFO = IINFO
 *
 *        Apply unitary matrix used in reduction to tridiagonal
 *        form to eigenvectors returned by CSTEIN.

lapack-netlib/SRC/chpevx.f

@@ -219,8 +219,11 @@
 *>          INFO is INTEGER
 *>          = 0:  successful exit
 *>          < 0:  if INFO = -i, the i-th argument had an illegal value
-*>          > 0:  if INFO = i, then i eigenvectors failed to converge.
-*>                Their indices are stored in array IFAIL.
+*>          > 0:  if INFO = i, and i is:
+*>                <= N: then i eigenvectors failed to converge in
+*>                     CSTEIN; their indices are stored in IFAIL.
+*>                > N: SSTEBZ returned INFO = INFO - N;
+*>                     see SSTEBZ for details.
 *> \endverbatim
 *
 *  Authors:
@@ -439,12 +442,19 @@ SUBROUTINE CHPEVX( JOBZ, RANGE, UPLO, N, AP, VL, VU, IL, IU,
       CALL SSTEBZ( RANGE, ORDER, N, VLL, VUU, IL, IU, ABSTLL,
      $             RWORK( INDD ), RWORK( INDE ), M, NSPLIT, W,
      $             IWORK( 1 ), IWORK( INDISP ), RWORK( INDRWK ),
-     $             IWORK( INDIWK ), INFO )
+     $             IWORK( INDIWK ), IINFO )
+      IF( IINFO.NE.0 ) THEN
+         INFO = N + IINFO
+         IF( IINFO.NE.1 )
+     $      GO TO 20
+      END IF
 *
       IF( WANTZ ) THEN
          CALL CSTEIN( N, RWORK( INDD ), RWORK( INDE ), M, W,
      $                IWORK( 1 ), IWORK( INDISP ), Z, LDZ,
-     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, INFO )
+     $                RWORK( INDRWK ), IWORK( INDIWK ), IFAIL, IINFO )
+         IF( IINFO.NE.0 .AND. INFO.EQ.0 )
+     $      INFO = IINFO
 *
 *        Apply unitary matrix used in reduction to tridiagonal
 *        form to eigenvectors returned by CSTEIN.

lapack-netlib/SRC/dsbevx.f

@@ -244,8 +244,11 @@
 *>          INFO is INTEGER
 *>          = 0:  successful exit.
 *>          < 0:  if INFO = -i, the i-th argument had an illegal value.
-*>          > 0:  if INFO = i, then i eigenvectors failed to converge.
-*>                Their indices are stored in array IFAIL.
+*>          > 0:  if INFO = i, and i is:
+*>                <= N: then i eigenvectors failed to converge in
+*>                     DSTEIN; their indices are stored in IFAIL.
+*>                > N: DSTEBZ returned INFO = INFO - N;
+*>                     see DSTEBZ for details.
 *> \endverbatim
 *
 *  Authors:
@@ -474,12 +477,19 @@ SUBROUTINE DSBEVX( JOBZ, RANGE, UPLO, N, KD, AB, LDAB, Q, LDQ, VL,
       CALL DSTEBZ( RANGE, ORDER, N, VLL, VUU, IL, IU, ABSTLL,
      $             WORK( INDD ), WORK( INDE ), M, NSPLIT, W,
      $             IWORK( INDIBL ), IWORK( INDISP ), WORK( INDWRK ),
-     $             IWORK( INDIWO ), INFO )
+     $             IWORK( INDIWO ), IINFO )
+      IF( IINFO.NE.0 ) THEN
+         INFO = N + IINFO
+         IF( IINFO.NE.1 )
+     $      GO TO 30
+      END IF
 *
       IF( WANTZ ) THEN
          CALL DSTEIN( N, WORK( INDD ), WORK( INDE ), M, W,
      $                IWORK( INDIBL ), IWORK( INDISP ), Z, LDZ,
-     $                WORK( INDWRK ), IWORK( INDIWO ), IFAIL, INFO )
+     $                WORK( INDWRK ), IWORK( INDIWO ), IFAIL, IINFO )
+         IF( IINFO.NE.0 .AND. INFO.EQ.0 )
+     $      INFO = IINFO
 *
 *        Apply orthogonal matrix used in reduction to tridiagonal
 *        form to eigenvectors returned by DSTEIN.

lapack-netlib/SRC/dsbevx_2stage.f

@@ -269,8 +269,11 @@
 *>          INFO is INTEGER
 *>          = 0:  successful exit.
 *>          < 0:  if INFO = -i, the i-th argument had an illegal value.
-*>          > 0:  if INFO = i, then i eigenvectors failed to converge.
-*>                Their indices are stored in array IFAIL.
+*>          > 0:  if INFO = i, and i is:
+*>                <= N: then i eigenvectors failed to converge in
+*>                     DSTEIN; their indices are stored in IFAIL.
+*>                > N: DSTEBZ returned INFO = INFO - N;
+*>                     see DSTEBZ for details.
 *> \endverbatim
 *
 *  Authors:
@@ -563,12 +566,19 @@ SUBROUTINE DSBEVX_2STAGE( JOBZ, RANGE, UPLO, N, KD, AB, LDAB, Q,
       CALL DSTEBZ( RANGE, ORDER, N, VLL, VUU, IL, IU, ABSTLL,
      $             WORK( INDD ), WORK( INDE ), M, NSPLIT, W,
      $             IWORK( INDIBL ), IWORK( INDISP ), WORK( INDWRK ),
-     $             IWORK( INDIWO ), INFO )
+     $             IWORK( INDIWO ), IINFO )
+      IF( IINFO.NE.0 ) THEN
+         INFO = N + IINFO
+         IF( IINFO.NE.1 )
+     $      GO TO 30
+      END IF
 *
       IF( WANTZ ) THEN
          CALL DSTEIN( N, WORK( INDD ), WORK( INDE ), M, W,
      $                IWORK( INDIBL ), IWORK( INDISP ), Z, LDZ,
-     $                WORK( INDWRK ), IWORK( INDIWO ), IFAIL, INFO )
+     $                WORK( INDWRK ), IWORK( INDIWO ), IFAIL, IINFO )
+         IF( IINFO.NE.0 .AND. INFO.EQ.0 )
+     $      INFO = IINFO
 *
 *        Apply orthogonal matrix used in reduction to tridiagonal
 *        form to eigenvectors returned by DSTEIN.

lapack-netlib/SRC/dsbgvx.f

@@ -263,13 +263,14 @@
 *>          INFO is INTEGER
 *>          = 0:  successful exit
 *>          < 0:  if INFO = -i, the i-th argument had an illegal value
-*>          <= N: if INFO = i, then i eigenvectors failed to converge.
-*>                  Their indices are stored in IFAIL.
-*>          > N:  DPBSTF returned an error code; i.e.,
-*>                if INFO = N + i, for 1 <= i <= N, then the leading
-*>                principal minor of order i of B is not positive.
-*>                The factorization of B could not be completed and
-*>                no eigenvalues or eigenvectors were computed.
+*>          <= N:    if INFO = i, then i eigenvectors failed to converge
+*>                   in DSTEIN; their indices are stored in IFAIL.
+*>          N+1..2N: if INFO = N + i, for 1 <= i <= N, then DPBSTF
+*>                   returned an error code; the leading principal minor
+*>                   of order i of B is not positive. No eigenvalues or
+*>                   eigenvectors were computed.
+*>          > 2N:    if INFO = 2*N + i, then DSTEBZ returned
+*>                   INFO = i; see DSTEBZ for details.
 *> \endverbatim
 *
 *  Authors:
@@ -462,12 +463,19 @@ SUBROUTINE DSBGVX( JOBZ, RANGE, UPLO, N, KA, KB, AB, LDAB, BB,
       CALL DSTEBZ( RANGE, ORDER, N, VL, VU, IL, IU, ABSTOL,
      $             WORK( INDD ), WORK( INDE ), M, NSPLIT, W,
      $             IWORK( 1 ), IWORK( INDISP ), WORK( INDWRK ),
-     $             IWORK( INDIWO ), INFO )
+     $             IWORK( INDIWO ), IINFO )
+      IF( IINFO.NE.0 ) THEN
+         INFO = 2*N + IINFO
+         IF( IINFO.NE.1 )
+     $      GO TO 30
+      END IF
 *
       IF( WANTZ ) THEN
          CALL DSTEIN( N, WORK( INDD ), WORK( INDE ), M, W,
      $                IWORK( 1 ), IWORK( INDISP ), Z, LDZ,
-     $                WORK( INDWRK ), IWORK( INDIWO ), IFAIL, INFO )
+     $                WORK( INDWRK ), IWORK( INDIWO ), IFAIL, IINFO )
+         IF( IINFO.NE.0 .AND. INFO.EQ.0 )
+     $      INFO = IINFO
 *
 *        Apply transformation matrix used in reduction to tridiagonal
 *        form to eigenvectors returned by DSTEIN.

lapack-netlib/SRC/dspevx.f

@@ -213,8 +213,11 @@
 *>          INFO is INTEGER
 *>          = 0:  successful exit
 *>          < 0:  if INFO = -i, the i-th argument had an illegal value
-*>          > 0:  if INFO = i, then i eigenvectors failed to converge.
-*>                Their indices are stored in array IFAIL.
+*>          > 0:  if INFO = i, and i is:
+*>                <= N: then i eigenvectors failed to converge in
+*>                     DSTEIN; their indices are stored in IFAIL.
+*>                > N: DSTEBZ returned INFO = INFO - N;
+*>                     see DSTEBZ for details.
 *> \endverbatim
 *
 *  Authors:
@@ -429,12 +432,19 @@ SUBROUTINE DSPEVX( JOBZ, RANGE, UPLO, N, AP, VL, VU, IL, IU,
       CALL DSTEBZ( RANGE, ORDER, N, VLL, VUU, IL, IU, ABSTLL,
      $             WORK( INDD ), WORK( INDE ), M, NSPLIT, W,
      $             IWORK( 1 ), IWORK( INDISP ), WORK( INDWRK ),
-     $             IWORK( INDIWO ), INFO )
+     $             IWORK( INDIWO ), IINFO )
+      IF( IINFO.NE.0 ) THEN
+         INFO = N + IINFO
+         IF( IINFO.NE.1 )
+     $      GO TO 20
+      END IF
 *
       IF( WANTZ ) THEN
          CALL DSTEIN( N, WORK( INDD ), WORK( INDE ), M, W,
      $                IWORK( 1 ), IWORK( INDISP ), Z, LDZ,
-     $                WORK( INDWRK ), IWORK( INDIWO ), IFAIL, INFO )
+     $                WORK( INDWRK ), IWORK( INDIWO ), IFAIL, IINFO )
+         IF( IINFO.NE.0 .AND. INFO.EQ.0 )
+     $      INFO = IINFO
 *
 *        Apply orthogonal matrix used in reduction to tridiagonal
 *        form to eigenvectors returned by DSTEIN.