public ExpressionTree(string expression)
{
string postfixExpression = ExpressionConverter.ConvertToPostFixNotation(expression);
List <string> tokens = postfixExpression.Split(' ').ToList();
Stack <IExpressionNode> tokenStack = new Stack <IExpressionNode>();
for (int i = 0; i < tokens.Count; i++)
{
if (tokens[i].IsNumber())
{
var newNode = new Constant(double.Parse(tokens[i]));
tokenStack.Push(newNode);
}
else if (tokens[i].IsVariable())
{
var newNode = new Variable(tokens[i]);
tokenStack.Push(newNode);
}
else if (tokens[i].IsOperator())
{
var op1 = tokenStack.Pop();
var op2 = tokenStack.Pop();
var temporary = (IOperation)Activator.CreateInstance(ParseHelper.tokenInformation[tokens[i]].nodeClass);
temporary.LeftOperand = op2;
temporary.RightOperand = op1;
tokenStack.Push(temporary);
}
else if (tokens[i].IsFunctionCall())
{
if (ParseHelper.tokenInformation[tokens[i]].numberOfParameters == 1)
{
var op1 = tokenStack.Pop();
var temporary = (IFunctionSingular)Activator.CreateInstance(ParseHelper.tokenInformation[tokens[i]].nodeClass);
temporary.Parameter = op1;
tokenStack.Push(temporary);
}
else
{
var op1 = tokenStack.Pop();
var op2 = tokenStack.Pop();
var temporary = (IFunctionDual)Activator.CreateInstance(ParseHelper.tokenInformation[tokens[i]].nodeClass);
temporary.FirstParameter = op2;
temporary.SecondParameter = op1;
tokenStack.Push(temporary);
}
}
}
this.root = tokenStack.Pop().Simplify();
}