zpbcon zpbtrf zpbtrs zptcon zpttrf zpttrs

zpbtrs() void zpbtrs ( char  uplo, int  n, int  kd, int  nrhs, int  ldab, doublecomplex  ab[], int  ldb, doublecomplex  b[], int *  info  ) Solution to factorized system of linear equations AX = B for a Hermitian positive definite band matrix Purpose This routine solves a system of linear equations A * X = B with a Hermitian positive definite band matrix A using the Cholesy factorization A = U^H*U or A = L*L^H computed by zpbtrf. Parameters [in] uplo = 'U': Upper triangular factor U is stored in ab[][]. = 'L': Lower triangular factor L is stored in ab[][]. [in] n Number of linear equations, i.e., order of the matrix A. (n >= 0) (If n = 0, returns without computation) [in] kd Number of super-diagonals of the matrix A if uplo = 'U', or number of sub-diagonals if uplo = 'L'. (kd >= 0) [in] nrhs Number of right hand sides, i.e., number of columns of the matrix B. (nrhs >= 0) (If nrhs = 0, returns without computation) [in] ldab Leading dimension of the two dimensional array ab[][]. (ldab >= kd + 1) [in] ab[][] Array ab[lab][ldab] (lab >= n) The triangular factor U or L from the Cholesky factorization A = U^H*U or A = L*L^H of the Hermitian positive definite band matrix A, stored in kd+1 x n symmetric band matrix form. [in] ldb Leading dimension of the two dimensional array b[][]. (ldb >= max(1, n)) [in,out] b[][] Array b[lb][ldb] (lb >= nrhs) [in] Right hand side matrix B. [out] Solution matrix X. [out] info = 0: Successful exit = -1: The argument uplo had an illegal value (uplo != 'U' nor 'L') = -2: The argument n had an illegal value (n < 0) = -3: The argument kd had an illegal value (kd < 0) = -4: The argument nrhs had an illegal value (nrhs < 0) = -5: The argument lda had an illegal value (lda < max(1, n)) = -7: The argument ldb had an illegal value (ldb < max(1, n)) Reference LAPACK