/**
   * A unit test suite for JUnit.
   *
   * @return The test suite
   */
  @Test
  public void testRemove_IMolecularFormulaSet_MolecularFormulaRange() {

    MolecularFormulaRange formulaRange = new MolecularFormulaRange();
    formulaRange.addIsotope(builder.newIsotope("C"), 0, 4);
    formulaRange.addIsotope(builder.newIsotope("H"), 0, 12);
    formulaRange.addIsotope(builder.newIsotope("N"), 0, 2);

    IMolecularFormula mf2 = new MolecularFormula();
    mf2.addIsotope(builder.newIsotope("C"), 1);
    mf2.addIsotope(builder.newIsotope("H"), 11);
    mf2.addIsotope(builder.newIsotope("N"), 1);

    IMolecularFormula mf1 = new MolecularFormula();
    mf1.addIsotope(builder.newIsotope("C"), 3);
    mf1.addIsotope(builder.newIsotope("H"), 10);

    IMolecularFormulaSet formulaSet = new MolecularFormulaSet();
    formulaSet.addMolecularFormula(mf1);
    formulaSet.addMolecularFormula(mf2);

    IMolecularFormulaSet newMFSet = MolecularFormulaSetManipulator.remove(formulaSet, formulaRange);
    /*the mf2 is excluded from the limits. It doesn't contain N*/

    Assert.assertEquals(2, newMFSet.size());
  }
  /**
   * A unit test suite for JUnit.
   *
   * @return The test suite
   */
  @Test
  public void testRemove_2() {

    IMolecularFormula formulaMin = new MolecularFormula();
    formulaMin.addIsotope(builder.newIsotope("C"), 1);
    formulaMin.addIsotope(builder.newIsotope("H"), 1);
    formulaMin.addIsotope(builder.newIsotope("N"), 1);

    IMolecularFormula formulaMax = new MolecularFormula();
    formulaMax.addIsotope(builder.newIsotope("C"), 4);
    formulaMax.addIsotope(builder.newIsotope("H"), 12);
    formulaMax.addIsotope(builder.newIsotope("N"), 2);

    IMolecularFormula mf1 = new MolecularFormula();
    mf1.addIsotope(builder.newIsotope("C"), 3);
    mf1.addIsotope(builder.newIsotope("H"), 10);
    mf1.addIsotope(builder.newIsotope("N"), 1);

    IMolecularFormula mf2 = new MolecularFormula();
    mf2.addIsotope(builder.newIsotope("C"), 1);
    mf2.addIsotope(builder.newIsotope("H"), 1);

    IMolecularFormulaSet formulaSet = new MolecularFormulaSet();
    formulaSet.addMolecularFormula(mf1);
    formulaSet.addMolecularFormula(mf2);

    IMolecularFormulaSet newMFSet =
        MolecularFormulaSetManipulator.remove(formulaSet, formulaMin, formulaMax);
    /*the mf2 is excluded from the limits. It doesn't contain N*/

    Assert.assertEquals(1, newMFSet.size());
    Assert.assertEquals(
        MolecularFormulaManipulator.getString(mf1),
        MolecularFormulaManipulator.getString(newMFSet.getMolecularFormula(0)));
  }