text: /* zptsv.f -- translated by f2c (version 20061008).
     You must link the resulting object file with libf2c:
  	on Microsoft Windows system, link with libf2c.lib;
  	on Linux or Unix systems, link with .../path/to/libf2c.a -lm
  	or, if you install libf2c.a in a standard place, with -lf2c -lm
  	-- in that order, at the end of the command line, as in
  		cc *.o -lf2c -lm
  	Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
  
  		http://www.netlib.org/f2c/libf2c.zip
  */
  
  #include "f2c.h"
  #include "blaswrap.h"
  
  /* Subroutine */ int zptsv_(integer *n, integer *nrhs, doublereal *d__, 
  	doublecomplex *e, doublecomplex *b, integer *ldb, integer *info)
  {
      /* System generated locals */
      integer b_dim1, b_offset, i__1;
  
      /* Local variables */
      extern /* Subroutine */ int xerbla_(char *, integer *), zpttrf_(
  	    integer *, doublereal *, doublecomplex *, integer *), zpttrs_(
  	    char *, integer *, integer *, doublereal *, doublecomplex *, 
  	    doublecomplex *, integer *, integer *);
  
  
  /*  -- LAPACK routine (version 3.2) -- */
  /*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
  /*     November 2006 */
  
  /*     .. Scalar Arguments .. */
  /*     .. */
  /*     .. Array Arguments .. */
  /*     .. */
  
  /*  Purpose */
  /*  ======= */
  
  /*  ZPTSV computes the solution to a complex system of linear equations */
  /*  A*X = B, where A is an N-by-N Hermitian positive definite tridiagonal */
  /*  matrix, and X and B are N-by-NRHS matrices. */
  
  /*  A is factored as A = L*D*L**H, and the factored form of A is then */
  /*  used to solve the system of equations. */
  
  /*  Arguments */
  /*  ========= */
  
  /*  N       (input) INTEGER */
  /*          The order of the matrix A.  N >= 0. */
  
  /*  NRHS    (input) INTEGER */
  /*          The number of right hand sides, i.e., the number of columns */
  /*          of the matrix B.  NRHS >= 0. */
  
  /*  D       (input/output) DOUBLE PRECISION array, dimension (N) */
  /*          On entry, the n diagonal elements of the tridiagonal matrix */
  /*          A.  On exit, the n diagonal elements of the diagonal matrix */
  /*          D from the factorization A = L*D*L**H. */
  
  /*  E       (input/output) COMPLEX*16 array, dimension (N-1) */
  /*          On entry, the (n-1) subdiagonal elements of the tridiagonal */
  /*          matrix A.  On exit, the (n-1) subdiagonal elements of the */
  /*          unit bidiagonal factor L from the L*D*L**H factorization of */
  /*          A.  E can also be regarded as the superdiagonal of the unit */
  /*          bidiagonal factor U from the U**H*D*U factorization of A. */
  
  /*  B       (input/output) COMPLEX*16 array, dimension (LDB,N) */
  /*          On entry, the N-by-NRHS right hand side matrix B. */
  /*          On exit, if INFO = 0, the N-by-NRHS solution matrix X. */
  
  /*  LDB     (input) INTEGER */
  /*          The leading dimension of the array B.  LDB >= max(1,N). */
  
  /*  INFO    (output) INTEGER */
  /*          = 0:  successful exit */
  /*          < 0:  if INFO = -i, the i-th argument had an illegal value */
  /*          > 0:  if INFO = i, the leading minor of order i is not */
  /*                positive definite, and the solution has not been */
  /*                computed.  The factorization has not been completed */
  /*                unless i = N. */
  
  /*  ===================================================================== */
  
  /*     .. External Subroutines .. */
  /*     .. */
  /*     .. Intrinsic Functions .. */
  /*     .. */
  /*     .. Executable Statements .. */
  
  /*     Test the input parameters. */
  
      /* Parameter adjustments */
      --d__;
      --e;
      b_dim1 = *ldb;
      b_offset = 1 + b_dim1;
      b -= b_offset;
  
      /* Function Body */
      *info = 0;
      if (*n < 0) {
  	*info = -1;
      } else if (*nrhs < 0) {
  	*info = -2;
      } else if (*ldb < max(1,*n)) {
  	*info = -6;
      }
      if (*info != 0) {
  	i__1 = -(*info);
  	xerbla_("ZPTSV ", &i__1);
  	return 0;
      }
  
  /*     Compute the L*D*L' (or U'*D*U) factorization of A. */
  
      zpttrf_(n, &d__[1], &e[1], info);
      if (*info == 0) {
  
  /*        Solve the system A*X = B, overwriting B with X. */
  
  	zpttrs_("Lower", n, nrhs, &d__[1], &e[1], &b[b_offset], ldb, info);
      }
      return 0;
  
  /*     End of ZPTSV */
  
  } /* zptsv_ */
  