schur_luinc2
LU incemental.
Syntax
[a, aa, LT, UT, PT] = schur_luinc2(a, b, L, U, P, A12, A21, A22, varargin)
Description
Performs an incremental-type LU factorization on an augmented matrix
[A11 A12; A21 A22], where PA = LU, A11 mxm, A12 mxn, A21 nxm and A22
nxn. To factorize A11 do [L, U, P] = lu(A11). The factorization of A22
is done without considering the elements of A12 for pivoting.
Nevertheless, A12 is updated according to the factorization on A11.
Input (required)
a = previous solution of the problem.
b = rhs of the system.
L = lower triangular factor from LU factorization of A.
U = upper triangular factor from LU factorization of A.
P = permutation matrix from LU factorization of A.
A12 = right-upper block for augmented matrix.
A21 = left-lower block for augmented matrix.
A22 = right-lower block for augmented matrix.
Input (optional)
precond = use precond or not ('no', 'ilu', 'diag').
for 'ndiad' define: 'numbd' (number of diagonals);
for 'ilu' define: 'milu', 'typeilu', 'droptol',
'thresh' and 'udiag'.
Output
a = next solution of the augmented problem.
aa = coefficients of the error estimation.
LT = augmented matrix lower triangular factor.
UT = augmented matrix upper triangular factor.
PT = augmented matrix permutation matrix.
See also
schur_luinc, schur_nflu and schur_iter.
Performs an incremental-type LU factorization on an augmented matrix [A11 A12; A21 A22], where PA = LU, A11 mxm, A12 mxn, A21 nxm and A22 nxn. To factorize A11 do [L, U, P] = lu(A11). The factorization of A22 is done without considering the elements of A12 for pivoting. Nevertheless, A12 is updated according to the factorization on A11.
Input (required)
a = previous solution of the problem.
b = rhs of the system.
L = lower triangular factor from LU factorization of A.
U = upper triangular factor from LU factorization of A.
P = permutation matrix from LU factorization of A.
A12 = right-upper block for augmented matrix.
A21 = left-lower block for augmented matrix.
A22 = right-lower block for augmented matrix.
Input (optional)
precond = use precond or not ('no', 'ilu', 'diag').
for 'ndiad' define: 'numbd' (number of diagonals);
for 'ilu' define: 'milu', 'typeilu', 'droptol',
'thresh' and 'udiag'.
Output
a = next solution of the augmented problem.
aa = coefficients of the error estimation.
LT = augmented matrix lower triangular factor.
UT = augmented matrix upper triangular factor.
PT = augmented matrix permutation matrix.
See also
schur_luinc, schur_nflu and schur_iter.
precond = use precond or not ('no', 'ilu', 'diag'). for 'ndiad' define: 'numbd' (number of diagonals); for 'ilu' define: 'milu', 'typeilu', 'droptol', 'thresh' and 'udiag'.
Output
a = next solution of the augmented problem.
aa = coefficients of the error estimation.
LT = augmented matrix lower triangular factor.
UT = augmented matrix upper triangular factor.
PT = augmented matrix permutation matrix.
See also
schur_luinc, schur_nflu and schur_iter.
schur_luinc, schur_nflu and schur_iter.