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Mise à jour de lapack vers la version 3.3.0.

    1:       SUBROUTINE ZTRTTP( UPLO, N, A, LDA, AP, INFO )
    2: *
    3: *  -- LAPACK routine (version 3.3.0) --
    4: *
    5: *  -- Contributed by Fred Gustavson of the IBM Watson Research Center --
    6: *  --            and Julien Langou of the Univ. of Colorado Denver    --
    7: *     November 2010                                                   --
    8: *
    9: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
   10: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
   11: *
   12: *     .. Scalar Arguments ..
   13:       CHARACTER          UPLO
   14:       INTEGER            INFO, N, LDA
   15: *     ..
   16: *     .. Array Arguments ..
   17:       COMPLEX*16         A( LDA, * ), AP( * )
   18: *     ..
   19: *
   20: *  Purpose
   21: *  =======
   22: *
   23: *  ZTRTTP copies a triangular matrix A from full format (TR) to standard
   24: *  packed format (TP).
   25: *
   26: *  Arguments
   27: *  =========
   28: *
   29: *  UPLO    (input) CHARACTER*1
   30: *          = 'U':  A is upper triangular;
   31: *          = 'L':  A is lower triangular.
   32: *
   33: *  N       (input) INTEGER
   34: *          The order of the matrices AP and A.  N >= 0.
   35: *
   36: *  A       (input) COMPLEX*16 array, dimension (LDA,N)
   37: *          On entry, the triangular matrix A.  If UPLO = 'U', the leading
   38: *          N-by-N upper triangular part of A contains the upper
   39: *          triangular part of the matrix A, and the strictly lower
   40: *          triangular part of A is not referenced.  If UPLO = 'L', the
   41: *          leading N-by-N lower triangular part of A contains the lower
   42: *          triangular part of the matrix A, and the strictly upper
   43: *          triangular part of A is not referenced.
   44: *
   45: *  LDA     (input) INTEGER
   46: *          The leading dimension of the array A.  LDA >= max(1,N).
   47: *
   48: *  AP      (output) COMPLEX*16 array, dimension ( N*(N+1)/2 ),
   49: *          On exit, the upper or lower triangular matrix A, packed
   50: *          columnwise in a linear array. The j-th column of A is stored
   51: *          in the array AP as follows:
   52: *          if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
   53: *          if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n.
   54: *
   55: *  INFO    (output) INTEGER
   56: *          = 0:  successful exit
   57: *          < 0:  if INFO = -i, the i-th argument had an illegal value
   58: *
   59: *  =====================================================================
   60: *
   61: *     .. Parameters ..
   62: *     ..
   63: *     .. Local Scalars ..
   64:       LOGICAL            LOWER
   65:       INTEGER            I, J, K
   66: *     ..
   67: *     .. External Functions ..
   68:       LOGICAL            LSAME
   69:       EXTERNAL           LSAME
   70: *     ..
   71: *     .. External Subroutines ..
   72:       EXTERNAL           XERBLA
   73: *     ..
   74: *     .. Executable Statements ..
   75: *
   76: *     Test the input parameters.
   77: *
   78:       INFO = 0
   79:       LOWER = LSAME( UPLO, 'L' )
   80:       IF( .NOT.LOWER .AND. .NOT.LSAME( UPLO, 'U' ) ) THEN
   81:          INFO = -1
   82:       ELSE IF( N.LT.0 ) THEN
   83:          INFO = -2
   84:       ELSE IF( LDA.LT.MAX( 1, N ) ) THEN
   85:          INFO = -4
   86:       END IF
   87:       IF( INFO.NE.0 ) THEN
   88:          CALL XERBLA( 'ZTRTTP', -INFO )
   89:          RETURN
   90:       END IF
   91: *
   92:       IF( LOWER ) THEN
   93:          K = 0
   94:          DO J = 1, N
   95:             DO I = J, N
   96:                K = K + 1
   97:                AP( K ) = A( I, J )
   98:             END DO
   99:          END DO
  100:       ELSE
  101:          K = 0
  102:          DO J = 1, N
  103:             DO I = 1, J
  104:                K = K + 1
  105:                AP( K ) = A( I, J )
  106:             END DO
  107:          END DO
  108:       END IF
  109: *
  110: *
  111:       RETURN
  112: *
  113: *     End of ZTRTTP
  114: *
  115:       END