bool EXParser::evaluateFunction(std::string &_expression, const int index, EXFunctionSet::iterator fiter)
{
std::string paramExpression = isolateParenthesisExpression(_expression, index);
size_t expressionLen = paramExpression.length();
if(expressionLen == 0){
mErrorStr = "function parameter error";
return false;
}
if(!priorityLoop(paramExpression))
return false;
double value = fiter->second((double)atof(paramExpression.c_str()));
if(isInf(value)){
mErrorStr = "infinity error";
return false;
}
if(isNan(value)){
mErrorStr = "not a number error";
return false;
}
steps.push_back(EXSolveStep(fiter->first+"("+paramExpression+") -> "+dblToStr(value), ""));
_expression.replace(index-fiter->first.length(), fiter->first.length()+expressionLen+2, dblToStr(value));
return true;
}
bool EXParser::priorityOperatorLoop(std::string &_expression)
{
for(EXOperatorSet::iterator oiter = operators.begin(); oiter!=operators.end(); ++oiter){
for(size_t index = 0; index<_expression.length(); index++){
if(oiter->first == _expression[index] && !isScientificNotation(_expression, index)){
if(oiter->first != '-' || !isNegitiveSign(_expression, index)){
std::string prevExpression = _expression;
if(!evaluateOperator(_expression, index, oiter))
return false;
steps.push_back(EXSolveStep(prevExpression.append(" -> ").append(_expression), std::string(&oiter->first, 1)));
oiter = operators.begin(); //reset operator loop to beginning
}
}
}
}
return true;
}
std::string EXParser::evaluate(std::string _expression)
{
steps.clear(); //clear previous solve steps
findAndReplaceVariables(_expression, this->variables);
try{
prepareExpression(_expression);
priorityLoop(_expression); //main calculation loop
}
catch(EXError &error){
steps.push_back(EXSolveStep(error.first, "stopped_evaluation"));
return error.first;
}
return _expression;
}
void EXParser::evaluateFunction(std::string &_expression, const int index, EXFunctionSet::iterator fiter)
{
std::string paramExpression = isolateParenthesisExpression(_expression, index);
size_t expressionLen = paramExpression.length();
if(expressionLen == 0){
throw EXError("function_parameter_error", ErrorIndex::FUNCTION_PARAMETER_ERROR);
}
priorityLoop(paramExpression);
double value = fiter->second((double)atof(paramExpression.c_str()));
if(isInf(value)){
throw EXError("infinity_error", ErrorIndex::INFINITY_ERROR);
}
if(isNan(value)){
throw EXError("not_a_number", ErrorIndex::NAN_ERROR);
}
steps.push_back(EXSolveStep(fiter->first+"("+paramExpression+") -> "+dblToStr(value), ""));
_expression.replace(index-fiter->first.length(), fiter->first.length()+expressionLen+2, dblToStr(value));
}
