Package org.ejml.dense.row.linsol

Class LinearSolver_DDRB_to_DDRM

java.lang.Object
org.ejml.dense.row.linsol.LinearSolver_DDRB_to_DDRM
All Implemented Interfaces:
LinearSolver<DMatrixRMaj,DMatrixRMaj>, LinearSolverDense<DMatrixRMaj>
Direct Known Subclasses:
LinearSolverChol_DDRB, LinearSolverQrBlock64_DDRM
public class LinearSolver_DDRB_to_DDRM extends Object implements LinearSolverDense<DMatrixRMaj>
Wrapper that allows DMatrixRBlock to implements LinearSolverDense. It works by converting DMatrixRMaj into DMatrixRBlock and calling the equivalent functions. Since a local copy is made all input matrices are never modified.

  • Field Details

  • Constructor Details

  • Method Details

    • setA

      public boolean setA(DMatrixRMaj A)
      Converts 'A' into a block matrix and call setA() on the block matrix solver.
      Specified by:
      setA in interface LinearSolver<DMatrixRMaj,DMatrixRMaj>
      Parameters:
      A - The A matrix in the linear equation. Not modified. Reference saved.
      Returns:
      true if it can solve the system.

    • 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 interface LinearSolver<DMatrixRMaj,DMatrixRMaj>
      Returns:
      The quality of the linear system.

    • solve

      public void solve(DMatrixRMaj B, DMatrixRMaj X)
      Converts B and X into block matrices and calls the block matrix solve routine.
      Specified by:
      solve in interface LinearSolver<DMatrixRMaj,DMatrixRMaj>
      Parameters:
      B - A matrix ℜ m × p. Not modified.
      X - A matrix ℜ n × p, where the solution is written to. Modified.

    • invert

      public void invert(DMatrixRMaj A_inv)
      Creates a block matrix the same size as A_inv, inverts the matrix and copies the results back onto A_inv.
      Specified by:
      invert in interface LinearSolverDense<DMatrixRMaj>
      Parameters:
      A_inv - Where the inverted matrix saved. Modified.

    • modifiesA

      public boolean modifiesA()
      Description copied from interface: LinearSolver
      Returns true if the passed in matrix to LinearSolver.setA(Matrix) is modified.
      Specified by:
      modifiesA in interface LinearSolver<DMatrixRMaj,DMatrixRMaj>
      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 to LinearSolver.solve(Matrix, Matrix) is modified.
      Specified by:
      modifiesB in interface LinearSolver<DMatrixRMaj,DMatrixRMaj>
      Returns:
      true if B is modified in solve(B,X).

    • getDecomposition

      public <D extends DecompositionInterface> D 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 interface LinearSolver<DMatrixRMaj,DMatrixRMaj>
      Type Parameters:
      D - Decomposition type
      Returns:
      Internal decomposition class. If there is none then null.