text: /* ztptrs.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"
  
  /* Table of constant values */
  
  static integer c__1 = 1;
  
  /* Subroutine */ int ztptrs_(char *uplo, char *trans, char *diag, integer *n, 
  	integer *nrhs, doublecomplex *ap, doublecomplex *b, integer *ldb, 
  	integer *info)
  {
      /* System generated locals */
      integer b_dim1, b_offset, i__1, i__2;
  
      /* Local variables */
      integer j, jc;
      extern logical lsame_(char *, char *);
      logical upper;
      extern /* Subroutine */ int ztpsv_(char *, char *, char *, integer *, 
  	    doublecomplex *, doublecomplex *, integer *), xerbla_(char *, integer *);
      logical nounit;
  
  
  /*  -- LAPACK routine (version 3.2) -- */
  /*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
  /*     November 2006 */
  
  /*     .. Scalar Arguments .. */
  /*     .. */
  /*     .. Array Arguments .. */
  /*     .. */
  
  /*  Purpose */
  /*  ======= */
  
  /*  ZTPTRS solves a triangular system of the form */
  
  /*     A * X = B,  A**T * X = B,  or  A**H * X = B, */
  
  /*  where A is a triangular matrix of order N stored in packed format, */
  /*  and B is an N-by-NRHS matrix.  A check is made to verify that A is */
  /*  nonsingular. */
  
  /*  Arguments */
  /*  ========= */
  
  /*  UPLO    (input) CHARACTER*1 */
  /*          = 'U':  A is upper triangular; */
  /*          = 'L':  A is lower triangular. */
  
  /*  TRANS   (input) CHARACTER*1 */
  /*          Specifies the form of the system of equations: */
  /*          = 'N':  A * X = B     (No transpose) */
  /*          = 'T':  A**T * X = B  (Transpose) */
  /*          = 'C':  A**H * X = B  (Conjugate transpose) */
  
  /*  DIAG    (input) CHARACTER*1 */
  /*          = 'N':  A is non-unit triangular; */
  /*          = 'U':  A is unit triangular. */
  
  /*  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. */
  
  /*  AP      (input) COMPLEX*16 array, dimension (N*(N+1)/2) */
  /*          The upper or lower triangular matrix A, packed columnwise in */
  /*          a linear array.  The j-th column of A is stored in the array */
  /*          AP as follows: */
  /*          if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j; */
  /*          if UPLO = 'L', AP(i + (j-1)*(2*n-j)/2) = A(i,j) for j<=i<=n. */
  
  /*  B       (input/output) COMPLEX*16 array, dimension (LDB,NRHS) */
  /*          On entry, the right hand side matrix B. */
  /*          On exit, if INFO = 0, the 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 i-th diagonal element of A is zero, */
  /*                indicating that the matrix is singular and the */
  /*                solutions X have not been computed. */
  
  /*  ===================================================================== */
  
  /*     .. Parameters .. */
  /*     .. */
  /*     .. Local Scalars .. */
  /*     .. */
  /*     .. External Functions .. */
  /*     .. */
  /*     .. External Subroutines .. */
  /*     .. */
  /*     .. Intrinsic Functions .. */
  /*     .. */
  /*     .. Executable Statements .. */
  
  /*     Test the input parameters. */
  
      /* Parameter adjustments */
      --ap;
      b_dim1 = *ldb;
      b_offset = 1 + b_dim1;
      b -= b_offset;
  
      /* Function Body */
      *info = 0;
      upper = lsame_(uplo, "U");
      nounit = lsame_(diag, "N");
      if (! upper && ! lsame_(uplo, "L")) {
  	*info = -1;
      } else if (! lsame_(trans, "N") && ! lsame_(trans, 
  	    "T") && ! lsame_(trans, "C")) {
  	*info = -2;
      } else if (! nounit && ! lsame_(diag, "U")) {
  	*info = -3;
      } else if (*n < 0) {
  	*info = -4;
      } else if (*nrhs < 0) {
  	*info = -5;
      } else if (*ldb < max(1,*n)) {
  	*info = -8;
      }
      if (*info != 0) {
  	i__1 = -(*info);
  	xerbla_("ZTPTRS", &i__1);
  	return 0;
      }
  
  /*     Quick return if possible */
  
      if (*n == 0) {
  	return 0;
      }
  
  /*     Check for singularity. */
  
      if (nounit) {
  	if (upper) {
  	    jc = 1;
  	    i__1 = *n;
  	    for (*info = 1; *info <= i__1; ++(*info)) {
  		i__2 = jc + *info - 1;
  		if (ap[i__2].r == 0. && ap[i__2].i == 0.) {
  		    return 0;
  		}
  		jc += *info;
  /* L10: */
  	    }
  	} else {
  	    jc = 1;
  	    i__1 = *n;
  	    for (*info = 1; *info <= i__1; ++(*info)) {
  		i__2 = jc;
  		if (ap[i__2].r == 0. && ap[i__2].i == 0.) {
  		    return 0;
  		}
  		jc = jc + *n - *info + 1;
  /* L20: */
  	    }
  	}
      }
      *info = 0;
  
  /*     Solve  A * x = b,  A**T * x = b,  or  A**H * x = b. */
  
      i__1 = *nrhs;
      for (j = 1; j <= i__1; ++j) {
  	ztpsv_(uplo, trans, diag, n, &ap[1], &b[j * b_dim1 + 1], &c__1);
  /* L30: */
      }
  
      return 0;
  
  /*     End of ZTPTRS */
  
  } /* ztptrs_ */
  