org.apache.commons.math3.linear

## Class SingularValueDecomposition.Solver

- java.lang.Object
- - org.apache.commons.math3.linear.SingularValueDecomposition.Solver

All Implemented Interfaces:
  DecompositionSolver

Enclosing class:
  SingularValueDecomposition

    private static class SingularValueDecomposition.Solver
    extends Object
    implements DecompositionSolver

Specialized solver.

### Field Summary

Fields
`private boolean` `nonSingular` Singularity indicator.
`private RealMatrix` `pseudoInverse` Pseudo-inverse of the initial matrix.

### Constructor Summary

Constructors
`private` `SingularValueDecomposition.Solver(double[] singularValues, RealMatrix uT, RealMatrix v, boolean nonSingular, double tol)` Build a solver from decomposed matrix.

### Method Summary

Methods
`RealMatrix` `getInverse()` Get the pseudo-inverse of the decomposed matrix.
`boolean` `isNonSingular()` Check if the decomposed matrix is non-singular.
`RealMatrix` `solve(RealMatrix b)` Solve the linear equation A × X = B in least square sense.
`RealVector` `solve(RealVector b)` Solve the linear equation A × X = B in least square sense.

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

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

### Field Detail

#### pseudoInverse

    private final RealMatrix pseudoInverse

Pseudo-inverse of the initial matrix.

#### nonSingular

    private boolean nonSingular

Singularity indicator.

### Constructor Detail

#### SingularValueDecomposition.Solver

    private SingularValueDecomposition.Solver(double[] singularValues,
                                     RealMatrix uT,
                                     RealMatrix v,
                                     boolean nonSingular,
                                     double tol)

Build a solver from decomposed matrix.

Parameters:
  `singularValues` - Singular values.
  `uT` - UT matrix of the decomposition.
  `v` - V matrix of the decomposition.
  `nonSingular` - Singularity indicator.
  `tol` - tolerance for singular values

### Method Detail

#### solve

    public RealVector solve(RealVector b)

Solve the linear equation A × X = B in least square sense.

The m×n matrix A may not be square, the solution X is such that ||A × X - B|| is minimal.

Specified by:
  `solve` in interface `DecompositionSolver`
Parameters:
  `b` - Right-hand side of the equation A × X = B
Returns:
  a vector X that minimizes the two norm of A × X - B
Throws:
  `DimensionMismatchException` - if the matrices dimensions do not match.

#### solve

    public RealMatrix solve(RealMatrix b)

Solve the linear equation A × X = B in least square sense.

The m×n matrix A may not be square, the solution X is such that ||A × X - B|| is minimal.

Specified by:
  `solve` in interface `DecompositionSolver`
Parameters:
  `b` - Right-hand side of the equation A × X = B
Returns:
  a matrix X that minimizes the two norm of A × X - B
Throws:
  `DimensionMismatchException` - if the matrices dimensions do not match.

#### isNonSingular

    public boolean isNonSingular()

Check if the decomposed matrix is non-singular.

Specified by:
  `isNonSingular` in interface `DecompositionSolver`
Returns:
  `true` if the decomposed matrix is non-singular.

#### getInverse

    public RealMatrix getInverse()

Get the pseudo-inverse of the decomposed matrix.

Specified by:
  `getInverse` in interface `DecompositionSolver`
Returns:
  the inverse matrix.