DiagonalMatrix extends AbstractRealMatrix implements Serializable { @Override public RealMatrix createMatrix(final int rowDimension, final int columnDimension) throws NotStrictlyPositiveException, DimensionMismatchException { if (rowDimension != columnDimension) { throw new DimensionMismatchException(rowDimension, columnDimension); } return new DiagonalMatrix(rowDimension); } DiagonalMatrix(final int dimension);  DiagonalMatrix(final double[] d);  DiagonalMatrix(final double[] d, final boolean copyArray); @Override RealMatrix createMatrix(final int rowDimension,
                                   final int columnDimension); @Override RealMatrix copy(); DiagonalMatrix add(final DiagonalMatrix m); DiagonalMatrix subtract(final DiagonalMatrix m); DiagonalMatrix multiply(final DiagonalMatrix m); @Override RealMatrix multiply(final RealMatrix m); @Override double[][] getData(); double[] getDataRef(); @Override double getEntry(final int row, final int column); @Override void setEntry(final int row, final int column, final double value); @Override void addToEntry(final int row,
                           final int column,
                           final double increment); @Override void multiplyEntry(final int row,
                              final int column,
                              final double factor); @Override int getRowDimension(); @Override int getColumnDimension(); @Override double[] operate(final double[] v); @Override double[] preMultiply(final double[] v); @Override RealVector preMultiply(final RealVector v); DiagonalMatrix inverse(); DiagonalMatrix inverse(double threshold); boolean isSingular(double threshold);  }
@Test(expected=DimensionMismatchException.class) public void testCreateError() { final double[] d = { -1.2, 3.4, 5 }; final DiagonalMatrix m = new DiagonalMatrix(d, false); m.createMatrix(5, 3); }