public CalcResult Solve (string input) {
ParseResult parseResult = this.ParseInput (input);
if (parseResult.Error != CalcError.None) {
return new CalcResult (parseResult.Error, parseResult.ErrorObject);
}
//Debug.WriteLine (parseResult.Output);
//return new CalcResult (1);
CalcResult result = this.ActualSolve (parseResult.Output);
if (result.Error == CalcError.None) {
result = new CalcResult (this.Round (result.Result));
this.constant.PreviousAnswer = result.Result;
}
return result;
}
public CalcResult Solve(string input)
{
ParseResult parseResult = this.ParseInput(input);
if (parseResult.Error != CalcError.None)
{
return(new CalcResult(parseResult.Error, parseResult.ErrorObject));
}
//Debug.WriteLine (parseResult.Output);
//return new CalcResult (1);
CalcResult result = this.ActualSolve(parseResult.Output);
if (result.Error == CalcError.None)
{
result = new CalcResult(this.Round(result.Result));
this.constant.PreviousAnswer = result.Result;
}
return(result);
}
private ParseResult ParseInput(string input)
{
//remove all whitespace and convert to lower
input = input.Replace(" ", "").ToLower();
CalcResult result = this.core.VerifyBrackets(input);
if (result.Error != CalcError.None)
{
return(new ParseResult(result.Error, result.ErrorObject));
}
result = this.function.VerifyBrackets(input);
if (result.Error != CalcError.None)
{
return(new ParseResult(result.Error, result.ErrorObject));
}
//convert negation sign to a specific negation function
input = this.ConvertNegationSign(input);
//output string list
List <string> output = new List <string> ();
//operator stack
Stack <string> stack = new Stack <string> ();
//parse token until input is empty
//shunting yard starts now!
while (input.Length > 0)
{
string token = "";
//check each module to see if they can find a token
foreach (IModule module in this.modules)
{
token = module.GetNextToken(input);
if (token != "")
{
break;
}
}
//no token means unrecognized input, bail
if (token == "")
{
return(new ParseResult(CalcError.UnknownToken, input));
}
//remove the found token from the input
input = this.RemoveTokenFromInput(input, token);
//if number or constant, push to output
if (this.core.IsNumber(token) || this.constant.IsToken(token))
{
output.Add(token);
}
else if (this.core.IsLeftBracket(token)) //if left bracket, push to stack
{
stack.Push(token);
}
else if (this.core.IsRightBracket(token)) //if right bracket, push all the things
//push stack onto output until left bracket is found
{
while (this.core.IsLeftBracket(stack.Peek()) == false)
{
output.Add(stack.Pop());
}
//throw away left bracket
stack.Pop();
}
else if (this.function.IsToken(token))
{
stack.Push(token);
}
else
{
//if operatorr token, apply precedence and associativity rules
if (this.operatorr.IsToken(token))
{
//if exponent, push to stack
if (this.operatorr.IsExponent(token) || this.operatorr.IsNegation(token))
{
stack.Push(token);
}
else //if other operatorr operators
//pop stack onto output as long as top of stack is more important than current operator
{
while (stack.Count > 0 && this.operatorr.Op1PrecedenceLessOrEqualOp2(token, stack.Peek()))
{
output.Add(stack.Pop());
}
stack.Push(token);
}
}
}
}
//join the output and the stack and return the string
return(new ParseResult((string.Join(" ", output) + " " + string.Join(" ", stack.ToArray())).Trim()));
}