/** * Checks whether the given column is basic. * @param col index of the column to check * @return the row that the variable is basic in. null if the column is not basic */ protected Integer getBasicRow(final int col) { Integer row = null; for (int i = 0; i < getHeight(); i++) { if (MathUtils.equals(getEntry(i, col), 1.0, epsilon) && (row == null)) { row = i; } else if (!MathUtils.equals(getEntry(i, col), 0.0, epsilon)) { return null; } } return row; }
/** * Checks whether the given column is basic. * @param col index of the column to check * @return the row that the variable is basic in. null if the column is not basic */ protected Integer getBasicRow(final int col) { Integer row = null; for (int i = 0; i < getHeight(); i++) { if (MathUtils.equals(getEntry(i, col), 1.0, epsilon) && (row == null)) { row = i; } else if (!MathUtils.equals(getEntry(i, col), 0.0, epsilon)) { return null; } } return row; }
for (int i = tableau.getNumObjectiveFunctions(); i < tableau.getHeight(); i++) { final double rhs = tableau.getEntry(i, tableau.getWidth() - 1); final double entry = tableau.getEntry(i, col);
for (int i = tableau.getNumObjectiveFunctions(); i < tableau.getHeight(); i++) { final double rhs = tableau.getEntry(i, tableau.getWidth() - 1); final double entry = tableau.getEntry(i, col);
/** * Runs one iteration of the Simplex method on the given model. * @param tableau simple tableau for the problem * @throws OptimizationException if the maximal iteration count has been * exceeded or if the model is found not to have a bounded solution */ protected void doIteration(final SimplexTableau tableau) throws OptimizationException { incrementIterationsCounter(); Integer pivotCol = getPivotColumn(tableau); Integer pivotRow = getPivotRow(tableau, pivotCol); if (pivotRow == null) { throw new UnboundedSolutionException(); } // set the pivot element to 1 double pivotVal = tableau.getEntry(pivotRow, pivotCol); tableau.divideRow(pivotRow, pivotVal); // set the rest of the pivot column to 0 for (int i = 0; i < tableau.getHeight(); i++) { if (i != pivotRow) { double multiplier = tableau.getEntry(i, pivotCol); tableau.subtractRow(i, pivotRow, multiplier); } } }
/** * Runs one iteration of the Simplex method on the given model. * @param tableau simple tableau for the problem * @throws OptimizationException if the maximal iteration count has been * exceeded or if the model is found not to have a bounded solution */ protected void doIteration(final SimplexTableau tableau) throws OptimizationException { incrementIterationsCounter(); Integer pivotCol = getPivotColumn(tableau); Integer pivotRow = getPivotRow(tableau, pivotCol); if (pivotRow == null) { throw new UnboundedSolutionException(); } // set the pivot element to 1 double pivotVal = tableau.getEntry(pivotRow, pivotCol); tableau.divideRow(pivotRow, pivotVal); // set the rest of the pivot column to 0 for (int i = 0; i < tableau.getHeight(); i++) { if (i != pivotRow) { double multiplier = tableau.getEntry(i, pivotCol); tableau.subtractRow(i, pivotRow, multiplier); } } }