ZTPTRS(l)		LAPACK routine (version	1.1)		    ZTPTRS(l)

NAME
  ZTPTRS - solve a triangular system of	the form   A * X = B, A**T * X = B,
  or A**H * X =	B,

SYNOPSIS

  SUBROUTINE ZTPTRS( UPLO, TRANS, DIAG,	N, NRHS, AP, B,	LDB, INFO )

      CHARACTER	     DIAG, TRANS, UPLO

      INTEGER	     INFO, LDB,	N, NRHS

      COMPLEX*16     AP( * ), B( LDB, *	)

PURPOSE
  ZTPTRS solves	a triangular system of the form

  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((j-1)*j/2 + i) = A(i,j) for 1<=i<=j; if
	  UPLO = 'L', AP((j-1)*(n-j) + j*(j+1)/2 + i-j)	= 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, indicat-
	  ing that the matrix is singular and the solutions X have not been
	  computed.


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