public IExpr evaluate(final IAST ast) {
IAST list = ast;
if (list.size() > 1) {
IAST resultList = list.copyHead();
if (AST.COPY.flatten(F.List, list, resultList, 1)) {
list = resultList;
}
// IExpr max = F.Times(F.CN1, ExprFactory.Infinity);
IExpr max1;
IExpr max2;
max1 = list.get(1);
IAST f = list.copyHead();
COMPARE_RESULT comp;
for (int i = 2; i < list.size(); i++) {
max2 = list.get(i);
comp = Less.CONST.prepareCompare(max1, max2);
if (comp == COMPARE_RESULT.TRUE) {
max1 = max2;
} else {
if (comp == COMPARE_RESULT.UNDEFINED) {
// undetermined
if (max1.isNumber()) {
f.add(max2);
} else {
f.add(max1);
max1 = max2;
}
}
}
}
if (f.size() > 1) {
f.add(1, max1);
if (f.equals(list)) {
return null;
}
return f;
} else {
return max1;
}
}
return null;
}
@Override
public IExpr evaluate(final IAST lst) {
if (lst.size() >= 3) {
try {
if (lst.get(1).isVector() < 0) {
return null;
}
if (lst.get(2).isVector() < 0) {
return null;
}
if (lst.size() == 3) {
IAST vars = (IAST) lst.get(2);
if (vars.size() <= 1) {
return null;
}
List<ISymbol> varList = new ArrayList<ISymbol>(vars.size() - 1);
String[] pvars = new String[vars.size() - 1];
for (int i = 1; i < vars.size(); i++) {
if (!vars.get(i).isSymbol()) {
return null;
}
varList.add((ISymbol) vars.get(i));
pvars[i - 1] = ((ISymbol) vars.get(i)).toString();
}
GroebnerBasePartial<BigRational> gbp = new GroebnerBasePartial<BigRational>();
IAST polys = (IAST) lst.get(1);
List<GenPolynomial<BigRational>> polyList =
new ArrayList<GenPolynomial<BigRational>>(polys.size() - 1);
JASConvert<BigRational> jas = new JASConvert<BigRational>(varList, BigRational.ZERO);
for (int i = 1; i < polys.size(); i++) {
IExpr expr = F.evalExpandAll(polys.get(i));
GenPolynomial<BigRational> poly = jas.expr2JAS(expr);
polyList.add(poly);
}
OptimizedPolynomialList<BigRational> opl = gbp.partialGB(polyList, pvars);
// System.out.println(opl);
IAST resultList = F.List();
for (GenPolynomial<BigRational> p : opl.list) {
// System.out.println(p);
resultList.add(jas.poly2Expr(p, null));
}
return resultList;
}
} catch (JASConversionException e) {
if (Config.SHOW_STACKTRACE) {
e.printStackTrace();
}
}
}
return null;
}
@Override
public IExpr evaluate(final IAST ast) {
if (ast.size() != 2) {
return null;
}
IExpr temp = roots(ast, true);
if (temp == null || !temp.isList()) {
return null;
}
IAST list = (IAST) temp;
IAST result = F.List();
for (int i = 1; i < list.size(); i++) {
result.add(F.evaln(list.get(i)));
}
return result;
}
@Override
public IExpr evaluate(final IAST ast) {
Validate.checkRange(ast, 3);
if (ast.size() == 3 && ast.get(2).isList() && ((IAST) ast.get(2)).size() == 4) {
IAST list = (IAST) ast.get(2);
if (ast.get(1).isPlus()) {
return ((IAST) ast.get(1)).map(Functors.replace1st(F.Sum(F.Null, ast.get(2))));
}
if (list.get(1).isSymbol() && list.get(2).isInteger() && list.get(3).isSymbol()) {
final ISymbol var = (ISymbol) list.get(1);
final IInteger from = (IInteger) list.get(2);
final ISymbol to = (ISymbol) list.get(3);
if (ast.get(1).isFree(var, true) && ast.get(1).isFree(to, true)) {
if (from.equals(F.C1)) {
return F.Times(to, ast.get(1));
}
if (from.equals(F.C0)) {
return F.Times(Plus(to, C1), ast.get(1));
}
} else {
if (ast.get(1).isTimes()) {
// Sum[ Times[a,b,c,...], {var, from, to} ]
IAST filterCollector = F.Times();
IAST restCollector = F.Times();
((IAST) ast.get(1))
.filter(
filterCollector,
restCollector,
new Predicate<IExpr>() {
@Override
public boolean apply(IExpr input) {
return input.isFree(var, true) && input.isFree(to, true);
}
});
if (filterCollector.size() > 1) {
if (restCollector.size() == 2) {
filterCollector.add(F.Sum(restCollector.get(1), ast.get(2)));
} else {
filterCollector.add(F.Sum(restCollector, ast.get(2)));
}
return filterCollector;
}
}
if (from.equals(F.C0)) {
IExpr repl =
ast.get(1).replaceAll(F.List(F.Rule(var, F.Slot(F.C1)), F.Rule(to, F.Slot(F.C2))));
if (repl != null) {
IExpr temp = MAP_0_N.get(repl);
if (temp != null) {
return temp.replaceAll(F.Rule(F.Slot(F.C1), to));
}
}
}
}
if (from.isPositive()) {
return F.Subtract(
F.Sum(ast.get(1), F.List(var, C0, to)),
F.Sum(ast.get(1), F.List(var, C0, from.minus(F.C1))));
}
}
}
IAST resultList = Plus();
IExpr temp = evaluateTable(ast, resultList, C0);
if (temp.equals(resultList)) {
return null;
}
return temp;
}