} else if( treeName.equalsIgnoreCase("tan") ) {
Object terms[] = parseTerms(fuzzyRuleSet, tree);
return new MffTan(fuzzyRuleSet, terms);
} else if( treeName.equalsIgnoreCase("abs") ) {
Object terms[] = parseTerms(fuzzyRuleSet, tree);
return new MffAbs(fuzzyRuleSet, terms);
} else {
// Try to parse it as a 'double'
try {
double dval = Double.parseDouble(treeName);
// Ok, it's a double