public double Calculate(string formulaText, IDictionary <string, double> variables)
{
if (string.IsNullOrEmpty(formulaText))
{
throw new ArgumentNullException("formulaText");
}
if (variables == null)
{
throw new ArgumentNullException("variables");
}
if (!caseSensitive)
{
variables = EngineUtil.ConvertVariableNamesToLowerCase(variables);
}
VerifyVariableNames(variables);
// Add the reserved variables to the dictionary
foreach (ConstantInfo constant in ConstantRegistry)
{
variables.Add(constant.ConstantName, constant.Value);
}
if (IsInFormulaCache(formulaText, null, out var function))
{
return(function(variables));
}
else
{
Operation operation = BuildAbstractSyntaxTree(formulaText, new ConstantRegistry(caseSensitive));
function = BuildFormula(formulaText, null, operation);
return(function(variables));
}
}
public double Calculate(string formulaText, Dictionary <string, double> variables)
{
if (formulaText == null)
{
throw new ArgumentNullException("formulaText");
}
if (variables == null)
{
throw new ArgumentNullException("variables");
}
variables = EngineUtil.ConvertVariableNamesToLowerCase(variables);
VerifyVariableNames(variables);
// Add the reserved variables to the dictionary
foreach (ConstantInfo constant in ConstantRegistry)
{
variables.Add(constant.ConstantName, constant.Value);
}
if (IsInFormulaCache(formulaText))
{
Func <Dictionary <string, double>, double> formula = executionFormulaCache[formulaText];
return(formula(variables));
}
else
{
Operation operation = BuildAbstractSyntaxTree(formulaText);
Func <Dictionary <string, double>, double> function = BuildFormula(formulaText, operation);
return(function(variables));
}
}
/// <summary>
/// Verify a collection of variables to ensure that all the variable names are valid.
/// Users are not allowed to overwrite reserved variables or use function names as variables.
/// If an invalid variable is detected an exception is thrown.
/// </summary>
/// <param name="variables">The colletion of variables that must be verified.</param>
private void VerifyVariableNames(Dictionary <string, double> variables)
{
foreach (string variableName in variables.Keys)
{
if (EngineUtil.IsReservedVariable(variableName))
{
throw new ArgumentException(string.Format("The name \"{0}\" is a reservered variable name that cannot be overwritten.", variableName), "variables");
}
if (FunctionRegistry.IsFunctionName(variableName))
{
throw new ArgumentException(string.Format("The name \"{0}\" is a function name. Parameters cannot have this name.", variableName), "variables");
}
}
}
public Operation Build(IList <Token> tokens)
{
resultStack.Clear();
operatorStack.Clear();
foreach (Token token in tokens)
{
object value = token.Value;
switch (token.TokenType)
{
case TokenType.Integer:
resultStack.Push(new IntegerConstant((int)token.Value));
break;
case TokenType.FloatingPoint:
resultStack.Push(new FloatingPointConstant((double)token.Value));
break;
case TokenType.Text:
if (EngineUtil.IsFunctionName((string)token.Value))
{
operatorStack.Push(token);
}
else
{
resultStack.Push(new Variable((string)token.Value));
}
break;
case TokenType.LeftBracket:
operatorStack.Push(token);
break;
case TokenType.RightBracket:
PopOperations(true, token);
break;
case TokenType.Operation:
Token operation1Token = token;
char operation1 = (char)operation1Token.Value;
if (operatorStack.Count == 0)
{
operatorStack.Push(operation1Token);
}
else
{
Token operation2Token = operatorStack.Peek();
bool isFunctionOnTopOfStack = operation2Token.TokenType == TokenType.Text;
if (!isFunctionOnTopOfStack)
{
char operation2 = (char)operation2Token.Value;
if ((IsLeftAssociativeOperation(operation1) && operationPrecedence[operation1] <= operationPrecedence[operation2]) ||
(operationPrecedence[operation1] < operationPrecedence[operation2]))
{
operatorStack.Pop();
operatorStack.Push(operation1Token);
resultStack.Push(ConvertOperation(operation2Token));
}
else
{
operatorStack.Push(operation1Token);
}
}
else
{
operatorStack.Pop();
operatorStack.Push(operation1Token);
resultStack.Push(ConvertFunction(operation2Token));
}
}
break;
}
}
PopOperations(false, null);
VerifyResultStack();
return(resultStack.First());
}