Class LinearSolverSparseSafe<S extends DMatrixSparse,D extends ReshapeMatrix>
 All Implemented Interfaces:
LinearSolver<S,
,D> LinearSolverSparse<S,
D>

Constructor Summary

Method Summary
Modifier and TypeMethodDescription<Decomposition extends DecompositionInterface>
DecompositionIf a decomposition class was used internally then this will return that class.boolean
Checks to see if the structure is locked.boolean
Returns true if the passed in matrix toLinearSolver.setA(Matrix)
is modified.boolean
Returns true if the passed in 'B' matrix toLinearSolver.solve(Matrix, Matrix)
is modified.double
quality()
Returns a very quick to compute measure of how singular the system is.boolean
Specifies the A matrix in the linear equation.void
setStructureLocked
(boolean locked) Save results from structural analysis step.void
Solves for X in the linear system, A*X=B.void
solveSparse
(S B, S X) Solve against sparse matrices.

Constructor Details

LinearSolverSparseSafe
 Parameters:
alg
 The solver it is wrapped around.


Method Details

setA
Description copied from interface:LinearSolver
Specifies the A matrix in the linear equation. A reference might be saved and it might also be modified depending on the implementation. If it is modified then
LinearSolver.modifiesA()
will return true.If this value returns true that does not guarantee a valid solution was generated. This is because some decompositions don't detect singular matrices.
 Specified by:
setA
in interfaceLinearSolver<S extends DMatrixSparse,
D extends ReshapeMatrix>  Parameters:
A
 The 'A' matrix in the linear equation. Might be modified or save the reference. Returns:
 true if it can be processed.

quality
public double quality()Description copied from interface:LinearSolver
Returns a very quick to compute measure of how singular the system is. This measure will be invariant to the scale of the matrix and always be positive, with larger values indicating it is less singular. If not supported by the solver then the runtime exception IllegalArgumentException is thrown. This is NOT the matrix's condition.
How this function is implemented is not specified. One possible implementation is the following: In many decompositions a triangular matrix is extracted. The determinant of a triangular matrix is easily computed and once normalized to be scale invariant and its absolute value taken it will provide functionality described above.
 Specified by:
quality
in interfaceLinearSolver<S extends DMatrixSparse,
D extends ReshapeMatrix>  Returns:
 The quality of the linear system.

solve
Description copied from interface:LinearSolver
Solves for X in the linear system, A*X=B.
In some implementations 'B' and 'X' can be the same instance of a variable. Call
LinearSolver.modifiesB()
to determine if 'B' is modified. Specified by:
solve
in interfaceLinearSolver<S extends DMatrixSparse,
D extends ReshapeMatrix>  Parameters:
B
 A matrix ℜ ^{m × p}. Might be modified.X
 A matrix ℜ ^{n × p}, where the solution is written to. Modified.

modifiesA
public boolean modifiesA()Description copied from interface:LinearSolver
Returns true if the passed in matrix toLinearSolver.setA(Matrix)
is modified. Specified by:
modifiesA
in interfaceLinearSolver<S extends DMatrixSparse,
D extends ReshapeMatrix>  Returns:
 true if A is modified in setA().

modifiesB
public boolean modifiesB()Description copied from interface:LinearSolver
Returns true if the passed in 'B' matrix toLinearSolver.solve(Matrix, Matrix)
is modified. Specified by:
modifiesB
in interfaceLinearSolver<S extends DMatrixSparse,
D extends ReshapeMatrix>  Returns:
 true if B is modified in solve(B,X).

getDecomposition
Description copied from interface:LinearSolver
If a decomposition class was used internally then this will return that class. Most linear solvers decompose the input matrix into a more simplistic form. However some solutions do not require decomposition, e.g. inverse by minor. Specified by:
getDecomposition
in interfaceLinearSolver<S extends DMatrixSparse,
D extends ReshapeMatrix>  Type Parameters:
Decomposition
 Decomposition type Returns:
 Internal decomposition class. If there is none then null.

solveSparse
Description copied from interface:LinearSolverSparse
Solve against sparse matrices. A*X=B. In most situations its more desirable to solve against a dense matrix because of fill in. Specified by:
solveSparse
in interfaceLinearSolverSparse<S extends DMatrixSparse,
D extends ReshapeMatrix>  Parameters:
B
 Input. Never modified.X
 Output. Never modified.

setStructureLocked
public void setStructureLocked(boolean locked) Description copied from interface:LinearSolverSparse
Save results from structural analysis step. This can reduce computations of a matrix with the exactly same nonzero pattern is decomposed in the future. If a matrix has yet to be processed then the structure of the next matrix is saved. If a matrix has already been processed then the structure of the most recently processed matrix will be saved.
 Specified by:
setStructureLocked
in interfaceLinearSolverSparse<S extends DMatrixSparse,
D extends ReshapeMatrix>

isStructureLocked
public boolean isStructureLocked()Description copied from interface:LinearSolverSparse
Checks to see if the structure is locked. Specified by:
isStructureLocked
in interfaceLinearSolverSparse<S extends DMatrixSparse,
D extends ReshapeMatrix>  Returns:
 true if locked or false if not locked.
