org.apache.commons.math3.linear

## Class FieldLUDecomposition.Solver<T extends FieldElement<T>>

- java.lang.Object
- - org.apache.commons.math3.linear.FieldLUDecomposition.Solver<T>

All Implemented Interfaces:
  FieldDecompositionSolver<T>

Enclosing class:
  FieldLUDecomposition<T extends FieldElement<T>>

    private static class FieldLUDecomposition.Solver<T extends FieldElement<T>>
    extends java.lang.Object
    implements FieldDecompositionSolver<T>

Specialized solver.

### Field Summary

Fields
`private Field<T>` `field` Field to which the elements belong.
`private T[][]` `lu` Entries of LU decomposition.
`private int[]` `pivot` Pivot permutation associated with LU decomposition.
`private boolean` `singular` Singularity indicator.

### Constructor Summary

Constructors
`private` `FieldLUDecomposition.Solver(Field<T> field, T[][] lu, int[] pivot, boolean singular)` Build a solver from decomposed matrix.

### Method Summary

Methods
`FieldMatrix<T>` `getInverse()` Get the inverse (or pseudo-inverse) of the decomposed matrix.
`boolean` `isNonSingular()` Check if the decomposed matrix is non-singular.
`ArrayFieldVector<T>` `solve(ArrayFieldVector<T> b)` Solve the linear equation A × X = B.
`FieldMatrix<T>` `solve(FieldMatrix<T> b)` Solve the linear equation A × X = B for matrices A.
`FieldVector<T>` `solve(FieldVector<T> b)` Solve the linear equation A × X = B for matrices A.

### Methods inherited from class java.lang.Object

`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

### Field Detail

#### field

    private final Field<T extends FieldElement<T>> field

Field to which the elements belong.

#### lu

    private final T extends FieldElement<T>[][] lu

Entries of LU decomposition.

#### pivot

    private final int[] pivot

Pivot permutation associated with LU decomposition.

#### singular

    private final boolean singular

Singularity indicator.

### Constructor Detail

#### FieldLUDecomposition.Solver

    private FieldLUDecomposition.Solver(Field<T> field,
                               T[][] lu,
                               int[] pivot,
                               boolean singular)

Build a solver from decomposed matrix.

Parameters:
  `field` - field to which the matrix elements belong
  `lu` - entries of LU decomposition
  `pivot` - pivot permutation associated with LU decomposition
  `singular` - singularity indicator

### Method Detail

#### isNonSingular

    public boolean isNonSingular()

Check if the decomposed matrix is non-singular.

Specified by:
  `isNonSingular` in interface `FieldDecompositionSolver<T extends FieldElement<T>>`
Returns:
  true if the decomposed matrix is non-singular

#### solve

    public FieldVector<T> solve(FieldVector<T> b)

Solve the linear equation A × X = B for matrices A.

The A matrix is implicit, it is provided by the underlying decomposition algorithm.

Specified by:
  `solve` in interface `FieldDecompositionSolver<T extends FieldElement<T>>`
Parameters:
  `b` - right-hand side of the equation A × X = B
Returns:
  a vector X that minimizes the two norm of A × X - B

#### solve

    public ArrayFieldVector<T> solve(ArrayFieldVector<T> b)

Solve the linear equation A × X = B.

The A matrix is implicit here. It is

Parameters:
  `b` - right-hand side of the equation A × X = B
Returns:
  a vector X such that A × X = B
Throws:
  `DimensionMismatchException` - if the matrices dimensions do not match.
  `SingularMatrixException` - if the decomposed matrix is singular.

#### solve

    public FieldMatrix<T> solve(FieldMatrix<T> b)

Solve the linear equation A × X = B for matrices A.

The A matrix is implicit, it is provided by the underlying decomposition algorithm.

Specified by:
  `solve` in interface `FieldDecompositionSolver<T extends FieldElement<T>>`
Parameters:
  `b` - right-hand side of the equation A × X = B
Returns:
  a matrix X that minimizes the two norm of A × X - B

#### getInverse

    public FieldMatrix<T> getInverse()

Get the inverse (or pseudo-inverse) of the decomposed matrix.

Specified by:
  `getInverse` in interface `FieldDecompositionSolver<T extends FieldElement<T>>`
Returns:
  inverse matrix