private BigInteger Solve()
{
if (_result == null)
{
_result = InfixNotation.Evaluate(Equation);
//_result = StaticScriptControl.Evaluate(Equation);
}
return((BigInteger)_result);
}
private decimal Solve()
{
if (_result == null)
{
_result = InfixNotation.Evaluate(Equation);
//_result = StaticScriptControl.Evaluate(Equation);
}
return((decimal)_result);
}
public static string Convert(string infixNotationString)
{
if (string.IsNullOrWhiteSpace(infixNotationString))
{
throw new ArgumentException("Argument infixNotationString must not be null, empty or whitespace.", "infixNotationString");
}
List <char> output = new List <char>();
Stack <char> operatorStack = new Stack <char>();
string sanitizedString = new string(infixNotationString.Where(c => AllowedCharacters.Contains(c)).ToArray());
string number = string.Empty;
List <string> enumerableInfixTokens = new List <string>();
foreach (char c in sanitizedString)
{
if (InfixNotation.Operators.Contains(c) || "()".Contains(c))
{
if (number.Length > 0)
{
enumerableInfixTokens.Add(number);
number = string.Empty;
}
enumerableInfixTokens.Add(c.ToString());
}
else if (InfixNotation.Numbers.Contains(c))
{
number += c.ToString();
}
else
{
throw new Exception(string.Format("Unexpected character '{0}'.", c));
}
}
if (number.Length > 0)
{
enumerableInfixTokens.Add(number);
number = string.Empty;
}
foreach (string token in enumerableInfixTokens)
{
if (InfixNotation.IsNumeric(token))
{
AddToOutput(output, token.ToArray());
}
else if (token.Length == 1)
{
char c = token[0];
if (InfixNotation.Numbers.Contains(c))
{
AddToOutput(output, c);
}
else if (InfixNotation.Operators.Contains(c))
{
if (operatorStack.Count > 0)
{
char o = operatorStack.Peek();
if ((AssociativityDictionary[c] == Associativity.Left &&
PrecedenceDictionary[c] <= PrecedenceDictionary[o])
||
(AssociativityDictionary[c] == Associativity.Right &&
PrecedenceDictionary[c] < PrecedenceDictionary[o]))
{
AddToOutput(output, operatorStack.Pop());
}
}
operatorStack.Push(c);
}
else if (c == '(')
{
operatorStack.Push(c);
}
else if (c == ')')
{
bool leftParenthesisFound = false;
while (operatorStack.Count > 0)
{
char o = operatorStack.Peek();
if (o != '(')
{
AddToOutput(output, operatorStack.Pop());
}
else
{
operatorStack.Pop();
leftParenthesisFound = true;
break;
}
}
if (!leftParenthesisFound)
{
throw new FormatException("The algebraic string contains mismatched parentheses (missing a left parenthesis).");
}
}
else
{
throw new Exception(string.Format("Unrecognized character '{0}'.", c));
}
}
else
{
throw new Exception(string.Format("String '{0}' is not numeric and has a length greater than 1.", token));
}
} // foreach
while (operatorStack.Count > 0)
{
char o = operatorStack.Pop();
if (o == '(')
{
throw new FormatException("The algebraic string contains mismatched parentheses (extra left parenthesis).");
}
else if (o == ')')
{
throw new FormatException("The algebraic string contains mismatched parentheses (extra right parenthesis).");
}
else
{
AddToOutput(output, o);
}
}
return(new string(output.ToArray()));
}
public static Expression <Func <BigInteger> > ExpressionTree(string postfixNotationString)
{
if (string.IsNullOrWhiteSpace(postfixNotationString))
{
throw new ArgumentException("Argument postfixNotationString must not be null, empty or whitespace.", "postfixNotationString");
}
Stack <Expression> stack = new Stack <Expression>();
string sanitizedString = new string(postfixNotationString.Where(c => AllowedCharacters.Contains(c)).ToArray());
List <string> enumerablePostfixTokens = sanitizedString.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).ToList();
foreach (string token in enumerablePostfixTokens)
{
if (token.Length < 1)
{
throw new Exception("Token.Length is less than one.");
}
BigInteger tokenValue = 0;
bool parseSuccess = BigInteger.TryParse(token, out tokenValue);
if (token.Length > 1) // Numbers > 10 will have a token length > 1
{
if (InfixNotation.IsNumeric(token) && parseSuccess)
{
stack.Push(Expression.Constant(tokenValue));
}
else
{
throw new Exception("Operators and operands must be separated by a space.");
}
}
else
{
char tokenChar = token[0];
if (InfixNotation.Numbers.Contains(tokenChar) && parseSuccess)
{
stack.Push(Expression.Constant(tokenValue));
}
else if (InfixNotation.Operators.Contains(tokenChar))
{
if (stack.Count < 2) // There must be two operands for the operator to operate on
{
throw new FormatException("The algebraic string has not sufficient values in the expression for the number of operators; There must be two operands for the operator to operate on.");
}
Expression left = stack.Pop();
Expression right = stack.Pop();
Expression operation = null;
/*
* // ^ token uses Math.Pow, which both gives and takes double, hence convert
* if (tokenChar == '^')
* {
* if (left.Type != typeof(double))
* {
* left = Expression.Convert(left, typeof(double));
* }
* if (right.Type != typeof(double))
* {
* right = Expression.Convert(right, typeof(double));
* }
* }
* else // Math.Pow returns a double, so we must check here for all other operators
* {
* if (left.Type != typeof(BigInteger))
* {
* left = Expression.Convert(left, typeof(BigInteger));
* }
* if (right.Type != typeof(BigInteger))
* {
* right = Expression.Convert(right, typeof(BigInteger));
* }
* }
*/
if (tokenChar == '+')
{
operation = Expression.AddChecked(left, right);
}
else if (tokenChar == '-')
{
operation = Expression.SubtractChecked(left, right);
}
else if (tokenChar == '*')
{
operation = Expression.MultiplyChecked(left, right);
}
else if (tokenChar == '/')
{
operation = Expression.Divide(left, right);
}
else if (tokenChar == '^')
{
operation = Expression.Power(left, right);
}
if (operation != null)
{
stack.Push(operation);
}
else
{
throw new Exception("Value never got set.");
}
}
else
{
throw new Exception(string.Format("Unrecognized character '{0}'.", tokenChar));
}
}
}
if (stack.Count == 1)
{
return(Expression.Lambda <Func <BigInteger> >(stack.Pop()));
}
else
{
throw new Exception("The input has too many values for the number of operators.");
}
} // method
} // method
public static BigInteger Evaluate(string postfixNotationString)
{
if (string.IsNullOrWhiteSpace(postfixNotationString))
{
throw new ArgumentException("Argument postfixNotationString must not be null, empty or whitespace.", "postfixNotationString");
}
Stack <string> stack = new Stack <string>();
string sanitizedString = new string(postfixNotationString.Where(c => AllowedCharacters.Contains(c)).ToArray());
List <string> enumerablePostfixTokens = sanitizedString.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).ToList();
foreach (string token in enumerablePostfixTokens)
{
if (token.Length > 0)
{
if (token.Length > 1)
{
if (InfixNotation.IsNumeric(token))
{
stack.Push(token);
}
else
{
throw new Exception("Operators and operands must be separated by a space.");
}
}
else
{
char tokenChar = token[0];
if (InfixNotation.Numbers.Contains(tokenChar))
{
stack.Push(tokenChar.ToString());
}
else if (InfixNotation.Operators.Contains(tokenChar))
{
if (stack.Count < 2)
{
throw new FormatException("The algebraic string has not sufficient values in the expression for the number of operators.");
}
string r = stack.Pop();
string l = stack.Pop();
BigInteger rhs = BigInteger.MinusOne;
BigInteger lhs = BigInteger.MinusOne;
bool parseSuccess = BigInteger.TryParse(r, out rhs);
parseSuccess &= BigInteger.TryParse(l, out lhs);
parseSuccess &= (rhs != BigInteger.MinusOne && lhs != BigInteger.MinusOne);
if (!parseSuccess)
{
throw new Exception("Unable to parse valueStack characters to Int32.");
}
BigInteger value = BigInteger.MinusOne;
if (tokenChar == '+')
{
value = lhs + rhs;
}
else if (tokenChar == '-')
{
value = lhs - rhs;
}
else if (tokenChar == '*')
{
value = lhs * rhs;
}
else if (tokenChar == '/')
{
value = lhs / rhs;
}
else if (tokenChar == '^')
{
value = HelperClass.Pow(lhs, rhs);
}
if (value != BigInteger.MinusOne)
{
stack.Push(value.ToString());
}
else
{
throw new Exception("Value never got set.");
}
}
else
{
throw new Exception(string.Format("Unrecognized character '{0}'.", tokenChar));
}
}
}
else
{
throw new Exception("Token length is less than one.");
}
}
if (stack.Count == 1)
{
BigInteger result = 0;
if (!BigInteger.TryParse(stack.Pop(), out result))
{
throw new Exception("Last value on stack could not be parsed into an integer.");
}
else
{
return(result);
}
}
else
{
throw new Exception("The input has too many values for the number of operators.");
}
} // method
