```DPBTRS(l)		LAPACK routine (version	1.1)		    DPBTRS(l)

NAME
DPBTRS - solve a system of linear equations A*X = B with a symmetric posi-
tive definite	band matrix A using the	Cholesky factorization A = U**T*U or
A = L*L**T computed by DPBTRF

SYNOPSIS

SUBROUTINE DPBTRS( UPLO, N, KD, NRHS,	AB, LDAB, B, LDB, INFO )

CHARACTER	     UPLO

INTEGER	     INFO, KD, LDAB, LDB, N, NRHS

DOUBLE	     PRECISION AB( LDAB, * ), B( LDB, *	)

PURPOSE
DPBTRS solves	a system of linear equations A*X = B with a symmetric posi-
tive definite	band matrix A using the	Cholesky factorization A = U**T*U or
A = L*L**T computed by DPBTRF.

ARGUMENTS

UPLO	  (input) CHARACTER*1
= 'U':  Upper	triangular factor stored in AB;
= 'L':  Lower	triangular factor stored in AB.

N	  (input) INTEGER
The order of the matrix A.  N	>= 0.

KD	  (input) INTEGER
The number of	superdiagonals of the matrix A if UPLO = 'U', or the
number of subdiagonals if UPLO = 'L'.	 KD >= 0.

NRHS	  (input) INTEGER
The number of	right hand sides, i.e.,	the number of columns of the
matrix B.  NRHS >= 0.

AB	  (input) DOUBLE PRECISION array, dimension (LDAB,N)
The triangular factor	U or L from the	Cholesky factorization A =
U**T*U or A =	L*L**T of the band matrix A, stored in the first KD+1
rows of the array.  The j-th column of U or L	is stored in the
array	AB as follows: if UPLO ='U', AB(kd+1+i-j,j) = U(i,j) for
max(1,j-kd)<=i<=j; if	UPLO ='L', AB(1+i-j,j)	  = L(i,j) for
j<=i<=min(n,j+kd).

LDAB	  (input) INTEGER
The leading dimension	of the array AB.  LDAB >= KD+1.

B	  (input/output) DOUBLE	PRECISION array, dimension (LDB,NRHS)
On entry, the	right hand side	matrix B.  On exit, 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
```

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