1DPBTRS(1)                LAPACK routine (version 3.2)                DPBTRS(1)
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NAME

6       DPBTRS  -  solves a system of linear equations A*X = B with a symmetric
7       positive definite band matrix A using the Cholesky  factorization  A  =
8       U**T*U or A = L*L**T computed by DPBTRF
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SYNOPSIS

11       SUBROUTINE DPBTRS( UPLO, N, KD, NRHS, AB, LDAB, B, LDB, INFO )
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13           CHARACTER      UPLO
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15           INTEGER        INFO, KD, LDAB, LDB, N, NRHS
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17           DOUBLE         PRECISION AB( LDAB, * ), B( LDB, * )
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PURPOSE

20       DPBTRS  solves  a  system  of linear equations A*X = B with a symmetric
21       positive definite band matrix A using the Cholesky  factorization  A  =
22       U**T*U or A = L*L**T computed by DPBTRF.
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ARGUMENTS

25       UPLO    (input) CHARACTER*1
26               = 'U':  Upper triangular factor stored in AB;
27               = 'L':  Lower triangular factor stored in AB.
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29       N       (input) INTEGER
30               The order of the matrix A.  N >= 0.
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32       KD      (input) INTEGER
33               The  number of superdiagonals of the matrix A if UPLO = 'U', or
34               the number of subdiagonals if UPLO = 'L'.  KD >= 0.
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36       NRHS    (input) INTEGER
37               The number of right hand sides, i.e., the number of columns  of
38               the matrix B.  NRHS >= 0.
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40       AB      (input) DOUBLE PRECISION array, dimension (LDAB,N)
41               The  triangular factor U or L from the Cholesky factorization A
42               = U**T*U or A = L*L**T of the band  matrix  A,  stored  in  the
43               first  KD+1  rows  of  the array.  The j-th column of U or L is
44               stored in the j-th column of the array AB as follows:  if  UPLO
45               ='U',  AB(kd+1+i-j,j)  =  U(i,j) for max(1,j-kd)<=i<=j; if UPLO
46               ='L', AB(1+i-j,j)    = L(i,j) for j<=i<=min(n,j+kd).
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48       LDAB    (input) INTEGER
49               The leading dimension of the array AB.  LDAB >= KD+1.
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51       B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)
52               On entry, the right hand side matrix B.  On exit, the  solution
53               matrix X.
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55       LDB     (input) INTEGER
56               The leading dimension of the array B.  LDB >= max(1,N).
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58       INFO    (output) INTEGER
59               = 0:  successful exit
60               < 0:  if INFO = -i, the i-th argument had an illegal value
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64 LAPACK routine (version 3.2)    November 2008                       DPBTRS(1)
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