Move LAPACK trunk into position.

1 files changed, 281 insertions, 0 deletions

diff --git a/SRC/dormbr.f b/SRC/dormbr.f
new file mode 100644
index 00000000..8066b893
--- /dev/null
+++ b/SRC/dormbr.f
@@ -0,0 +1,281 @@
+      SUBROUTINE DORMBR( VECT, SIDE, TRANS, M, N, K, A, LDA, TAU, C,
+     $                   LDC, WORK, LWORK, INFO )
+*
+*  -- LAPACK routine (version 3.1) --
+*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
+*     November 2006
+*
+*     .. Scalar Arguments ..
+      CHARACTER          SIDE, TRANS, VECT
+      INTEGER            INFO, K, LDA, LDC, LWORK, M, N
+*     ..
+*     .. Array Arguments ..
+      DOUBLE PRECISION   A( LDA, * ), C( LDC, * ), TAU( * ), WORK( * )
+*     ..
+*
+*  Purpose
+*  =======
+*
+*  If VECT = 'Q', DORMBR overwrites the general real M-by-N matrix C
+*  with
+*                  SIDE = 'L'     SIDE = 'R'
+*  TRANS = 'N':      Q * C          C * Q
+*  TRANS = 'T':      Q**T * C       C * Q**T
+*
+*  If VECT = 'P', DORMBR overwrites the general real M-by-N matrix C
+*  with
+*                  SIDE = 'L'     SIDE = 'R'
+*  TRANS = 'N':      P * C          C * P
+*  TRANS = 'T':      P**T * C       C * P**T
+*
+*  Here Q and P**T are the orthogonal matrices determined by DGEBRD when
+*  reducing a real matrix A to bidiagonal form: A = Q * B * P**T. Q and
+*  P**T are defined as products of elementary reflectors H(i) and G(i)
+*  respectively.
+*
+*  Let nq = m if SIDE = 'L' and nq = n if SIDE = 'R'. Thus nq is the
+*  order of the orthogonal matrix Q or P**T that is applied.
+*
+*  If VECT = 'Q', A is assumed to have been an NQ-by-K matrix:
+*  if nq >= k, Q = H(1) H(2) . . . H(k);
+*  if nq < k, Q = H(1) H(2) . . . H(nq-1).
+*
+*  If VECT = 'P', A is assumed to have been a K-by-NQ matrix:
+*  if k < nq, P = G(1) G(2) . . . G(k);
+*  if k >= nq, P = G(1) G(2) . . . G(nq-1).
+*
+*  Arguments
+*  =========
+*
+*  VECT    (input) CHARACTER*1
+*          = 'Q': apply Q or Q**T;
+*          = 'P': apply P or P**T.
+*
+*  SIDE    (input) CHARACTER*1
+*          = 'L': apply Q, Q**T, P or P**T from the Left;
+*          = 'R': apply Q, Q**T, P or P**T from the Right.
+*
+*  TRANS   (input) CHARACTER*1
+*          = 'N':  No transpose, apply Q  or P;
+*          = 'T':  Transpose, apply Q**T or P**T.
+*
+*  M       (input) INTEGER
+*          The number of rows of the matrix C. M >= 0.
+*
+*  N       (input) INTEGER
+*          The number of columns of the matrix C. N >= 0.
+*
+*  K       (input) INTEGER
+*          If VECT = 'Q', the number of columns in the original
+*          matrix reduced by DGEBRD.
+*          If VECT = 'P', the number of rows in the original
+*          matrix reduced by DGEBRD.
+*          K >= 0.
+*
+*  A       (input) DOUBLE PRECISION array, dimension
+*                                (LDA,min(nq,K)) if VECT = 'Q'
+*                                (LDA,nq)        if VECT = 'P'
+*          The vectors which define the elementary reflectors H(i) and
+*          G(i), whose products determine the matrices Q and P, as
+*          returned by DGEBRD.
+*
+*  LDA     (input) INTEGER
+*          The leading dimension of the array A.
+*          If VECT = 'Q', LDA >= max(1,nq);
+*          if VECT = 'P', LDA >= max(1,min(nq,K)).
+*
+*  TAU     (input) DOUBLE PRECISION array, dimension (min(nq,K))
+*          TAU(i) must contain the scalar factor of the elementary
+*          reflector H(i) or G(i) which determines Q or P, as returned
+*          by DGEBRD in the array argument TAUQ or TAUP.
+*
+*  C       (input/output) DOUBLE PRECISION array, dimension (LDC,N)
+*          On entry, the M-by-N matrix C.
+*          On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q
+*          or P*C or P**T*C or C*P or C*P**T.
+*
+*  LDC     (input) INTEGER
+*          The leading dimension of the array C. LDC >= max(1,M).
+*
+*  WORK    (workspace/output) DOUBLE PRECISION array, dimension (MAX(1,LWORK))
+*          On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
+*
+*  LWORK   (input) INTEGER
+*          The dimension of the array WORK.
+*          If SIDE = 'L', LWORK >= max(1,N);
+*          if SIDE = 'R', LWORK >= max(1,M).
+*          For optimum performance LWORK >= N*NB if SIDE = 'L', and
+*          LWORK >= M*NB if SIDE = 'R', where NB is the optimal
+*          blocksize.
+*
+*          If LWORK = -1, then a workspace query is assumed; the routine
+*          only calculates the optimal size of the WORK array, returns
+*          this value as the first entry of the WORK array, and no error
+*          message related to LWORK is issued by XERBLA.
+*
+*  INFO    (output) INTEGER
+*          = 0:  successful exit
+*          < 0:  if INFO = -i, the i-th argument had an illegal value
+*
+*  =====================================================================
+*
+*     .. Local Scalars ..
+      LOGICAL            APPLYQ, LEFT, LQUERY, NOTRAN
+      CHARACTER          TRANST
+      INTEGER            I1, I2, IINFO, LWKOPT, MI, NB, NI, NQ, NW
+*     ..
+*     .. External Functions ..
+      LOGICAL            LSAME
+      INTEGER            ILAENV
+      EXTERNAL           LSAME, ILAENV
+*     ..
+*     .. External Subroutines ..
+      EXTERNAL           DORMLQ, DORMQR, XERBLA
+*     ..
+*     .. Intrinsic Functions ..
+      INTRINSIC          MAX, MIN
+*     ..
+*     .. Executable Statements ..
+*
+*     Test the input arguments
+*
+      INFO = 0
+      APPLYQ = LSAME( VECT, 'Q' )
+      LEFT = LSAME( SIDE, 'L' )
+      NOTRAN = LSAME( TRANS, 'N' )
+      LQUERY = ( LWORK.EQ.-1 )
+*
+*     NQ is the order of Q or P and NW is the minimum dimension of WORK
+*
+      IF( LEFT ) THEN
+         NQ = M
+         NW = N
+      ELSE
+         NQ = N
+         NW = M
+      END IF
+      IF( .NOT.APPLYQ .AND. .NOT.LSAME( VECT, 'P' ) ) THEN
+         INFO = -1
+      ELSE IF( .NOT.LEFT .AND. .NOT.LSAME( SIDE, 'R' ) ) THEN
+         INFO = -2
+      ELSE IF( .NOT.NOTRAN .AND. .NOT.LSAME( TRANS, 'T' ) ) THEN
+         INFO = -3
+      ELSE IF( M.LT.0 ) THEN
+         INFO = -4
+      ELSE IF( N.LT.0 ) THEN
+         INFO = -5
+      ELSE IF( K.LT.0 ) THEN
+         INFO = -6
+      ELSE IF( ( APPLYQ .AND. LDA.LT.MAX( 1, NQ ) ) .OR.
+     $         ( .NOT.APPLYQ .AND. LDA.LT.MAX( 1, MIN( NQ, K ) ) ) )
+     $          THEN
+         INFO = -8
+      ELSE IF( LDC.LT.MAX( 1, M ) ) THEN
+         INFO = -11
+      ELSE IF( LWORK.LT.MAX( 1, NW ) .AND. .NOT.LQUERY ) THEN
+         INFO = -13
+      END IF
+*
+      IF( INFO.EQ.0 ) THEN
+         IF( APPLYQ ) THEN
+            IF( LEFT ) THEN
+               NB = ILAENV( 1, 'DORMQR', SIDE // TRANS, M-1, N, M-1,
+     $              -1 )
+            ELSE
+               NB = ILAENV( 1, 'DORMQR', SIDE // TRANS, M, N-1, N-1,
+     $              -1 )
+            END IF
+         ELSE
+            IF( LEFT ) THEN
+               NB = ILAENV( 1, 'DORMLQ', SIDE // TRANS, M-1, N, M-1,
+     $              -1 )
+            ELSE
+               NB = ILAENV( 1, 'DORMLQ', SIDE // TRANS, M, N-1, N-1,
+     $              -1 )
+            END IF
+         END IF
+         LWKOPT = MAX( 1, NW )*NB
+         WORK( 1 ) = LWKOPT
+      END IF
+*
+      IF( INFO.NE.0 ) THEN
+         CALL XERBLA( 'DORMBR', -INFO )
+         RETURN
+      ELSE IF( LQUERY ) THEN
+         RETURN
+      END IF
+*
+*     Quick return if possible
+*
+      WORK( 1 ) = 1
+      IF( M.EQ.0 .OR. N.EQ.0 )
+     $   RETURN
+*
+      IF( APPLYQ ) THEN
+*
+*        Apply Q
+*
+         IF( NQ.GE.K ) THEN
+*
+*           Q was determined by a call to DGEBRD with nq >= k
+*
+            CALL DORMQR( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC,
+     $                   WORK, LWORK, IINFO )
+         ELSE IF( NQ.GT.1 ) THEN
+*
+*           Q was determined by a call to DGEBRD with nq < k
+*
+            IF( LEFT ) THEN
+               MI = M - 1
+               NI = N
+               I1 = 2
+               I2 = 1
+            ELSE
+               MI = M
+               NI = N - 1
+               I1 = 1
+               I2 = 2
+            END IF
+            CALL DORMQR( SIDE, TRANS, MI, NI, NQ-1, A( 2, 1 ), LDA, TAU,
+     $                   C( I1, I2 ), LDC, WORK, LWORK, IINFO )
+         END IF
+      ELSE
+*
+*        Apply P
+*
+         IF( NOTRAN ) THEN
+            TRANST = 'T'
+         ELSE
+            TRANST = 'N'
+         END IF
+         IF( NQ.GT.K ) THEN
+*
+*           P was determined by a call to DGEBRD with nq > k
+*
+            CALL DORMLQ( SIDE, TRANST, M, N, K, A, LDA, TAU, C, LDC,
+     $                   WORK, LWORK, IINFO )
+         ELSE IF( NQ.GT.1 ) THEN
+*
+*           P was determined by a call to DGEBRD with nq <= k
+*
+            IF( LEFT ) THEN
+               MI = M - 1
+               NI = N
+               I1 = 2
+               I2 = 1
+            ELSE
+               MI = M
+               NI = N - 1
+               I1 = 1
+               I2 = 2
+            END IF
+            CALL DORMLQ( SIDE, TRANST, MI, NI, NQ-1, A( 1, 2 ), LDA,
+     $                   TAU, C( I1, I2 ), LDC, WORK, LWORK, IINFO )
+         END IF
+      END IF
+      WORK( 1 ) = LWKOPT
+      RETURN
+*
+*     End of DORMBR
+*
+      END