MATLAB Mathematics - SERC - Index of

Sparse Matrix Operations
preordering, is performed before the factorization of A. In some cases, you might
be able to provide a better preordering than the one used by the backslash
algorithm.
To use a different preordering, first turn off both of the automatic preorderings
that backslash might perform by default, using the function spparms as follows:
spparms('autoamd',0);
spparms('autommd',0);
Now, assuming you have created a permutation vector p that specifies a
preordering of the indices of A, apply backslash to the matrix A(:,p), whose
columns are the columns of A, permuted according to the vector p.
x = A (:,p) \ b;
x(p) = x;
spparms('autoamd',1);
spparms('autommd',1);
The commands spparms('autoamd',1) and spparms('autommd',1) turns the
automatic preordering back on, in case you use A\b later without specifying an
appropriate preordering.
Iterative Methods
Nine functions are available that implement iterative methods for sparse
systems of simultaneous linear systems.
Functions for Iterative Methods for Sparse Systems
Function
bicg
bicgstab
cgs
gmres
lsqr
minres
pcg
Method
Biconjugate gradient
Biconjugate gradient stabilized
Conjugate gradient squared
Generalized minimum residual
Least squares
Minimum residual
Preconditioned conjugate gradient
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