public double GetCalculation(string expression)
{
double result = 0;
ExpressionToReversePolish expressionToReversePolish = new ExpressionToReversePolish();
ReversePolishOperations reversePolishOperations = new ReversePolishOperations();
List <string> reversePolish = expressionToReversePolish.GetReversePolish(expression);
Stack <double> equateStack = new Stack <double>();
foreach (string element in reversePolish)
{
if (reversePolishOperations.IsStatement(element))
{
result = StackEquation(equateStack, element);
equateStack.Push(result);
}
else
{
equateStack.Push(Convert.ToDouble(element));
}
}
return(result);
}
public List <string> GetReversePolish(string expression)
{
List <string> result = new List <string>();
Stack <char> statementStack = new Stack <char>();
expression = expression.Replace(" ", String.Empty);
expression = expression.Replace(".", ",");
ReversePolishOperations reversePolishOperations = new ReversePolishOperations();
Console.WriteLine(expression);
for (int index = 0; index < expression.Length; index++)
{
if (reversePolishOperations.IsNumberOrFractional(expression[index]))
{
string number = String.Empty;
while ((index != expression.Length) && (reversePolishOperations.IsNumberOrFractional(expression[index])))
{
number += expression[index];
index++;
}
result.Add(number);
if (index == expression.Length)
{
break;
}
}
if (reversePolishOperations.IsStatement(expression[index]))
{
if (expression[index] == '(')
{
statementStack.Push(expression[index]);
}
else if (expression[index] == ')')
{
char statement = statementStack.Pop();
while (statement != '(')
{
result.Add(statement.ToString());
statement = statementStack.Pop();
}
}
else
{
while ((statementStack.Count != 0) && (reversePolishOperations.PriorityCheck(expression[index]) <= reversePolishOperations.PriorityCheck(statementStack.Peek())))
{
result.Add(statementStack.Pop().ToString());
}
statementStack.Push(expression[index]);
}
}
}
while (statementStack.Count() > 0)
{
result.Add(statementStack.Pop().ToString());
}
return(result);
}
