Example #1
0
  /**
   * Returns if a simple expression is greater than, less than, or equal to the other.
   *
   * @param se1 the first simple expression.
   * @param se2 the second simple expression.
   * @return the comparison result (-1, 0, 1).
   */
  public int compare(SimpleExpression se1, SimpleExpression se2) {
    if (se1.order < se2.order) return -1;
    else if (se1.order > se2.order) return 1;

    se1 = se1.getTerm();
    se2 = se2.getTerm();
    if (se1.children.size() < se2.children.size()) return -1;
    else if (se1.children.size() > se2.children.size()) return 1;
    else return se1.compareTo(se2);
  }
Example #2
0
  // Assumes se1 and se2 have been normalized.
  // Returns a triplet (gcd, dividend1, dividend2).
  private static List<SimpleExpression> computeGCD(SimpleExpression se1, SimpleExpression se2) {
    // Compute symbolic parts.
    List<SimpleExpression> terms1 = new LinkedList<SimpleExpression>();
    List<SimpleExpression> terms2 = new LinkedList<SimpleExpression>();
    SimpleExpression term1 = se1.getTerm(), term2 = se2.getTerm();
    if (term1.sop == MUL) terms1.addAll(term1.children);
    else terms1.add(term1);
    if (term2.sop == MUL) terms2.addAll(term2.children);
    else terms2.add(term2);
    TreeSet<SimpleExpression> gcd_terms = new TreeSet<SimpleExpression>(terms1);
    gcd_terms.retainAll(terms2);
    for (SimpleExpression gcd_term : gcd_terms) {
      terms1.remove(gcd_term); // removes the first occurrence
      terms2.remove(gcd_term); //   of the gcd term
    }
    // Compute numeric parts.
    SimpleExpression s1 = se1.getCoef(), s2 = se2.getCoef(), sgcd = null;
    if (s1.expr instanceof IntegerLiteral && s2.expr instanceof IntegerLiteral) {
      int n1 = s1.getValue().intValue(), n2 = s2.getValue().intValue();
      int gcd = cetus.analysis.GCD.compute(n1, n2);
      s1 = getInt(n1 / gcd);
      s2 = getInt(n2 / gcd);
      sgcd = getInt(gcd);
    } else sgcd = sone;
    // Combine two parts.
    for (SimpleExpression child : gcd_terms) sgcd = multiply(sgcd, child);
    for (SimpleExpression child : terms1) s1 = multiply(s1, child);
    for (SimpleExpression child : terms2) s2 = multiply(s2, child);

    List<SimpleExpression> ret = new LinkedList<SimpleExpression>();
    ret.add(sgcd);
    ret.add(s1);
    ret.add(s2);
    // Tools.printlnStatus("[GCD] "+se1+" and "+se2+" --> "+ret, 1);
    return ret;
  }
Example #3
0
  // Normalizes an ADD expression
  private SimpleExpression normalizeADD() {
    if (!allow(FOLD)) return this;
    TreeMap<SimpleExpression, SimpleExpression> terms =
        new TreeMap<SimpleExpression, SimpleExpression>();
    for (SimpleExpression child : children) {
      SimpleExpression term = child.getTerm(), coef = child.getCoef();
      if (terms.containsKey(term)) terms.put(term, add(terms.get(term), coef));
      else terms.put(term, coef);
    }

    SimpleExpression ret = new SimpleExpression(ADD);
    for (SimpleExpression term : terms.keySet()) {
      SimpleExpression coef = terms.get(term);
      if (!coef.equals(szero)) ret.add((coef.equals(sone)) ? term : multiply(coef, term));
    }

    if (ret.children.size() == 0) ret = szero;
    else if (ret.children.size() == 1) ret = ret.getChild(0);
    // Tools.printlnStatus("[ADD] "+this+" --> "+ret, 1);

    return ret;
  }