public CalculationResult Calculate(string expression, params Parameter[] parameters)
{
var dict = new Dictionary <string, double>();
foreach (var parameter in parameters)
{
dict[parameter.Name] = parameter.Value;
}
var exp = _calculator.ParseExpression(expression, dict);
var value = exp.Compile().Invoke();
return(new CalculationResult(value, ExtractCalledFunctions(exp).ToArray()));
}
/// <summary>
/// Calculates the value for a given calculation expression based on the supplied datafields (if datafields are part of the calculation expression)
/// </summary>
/// <param name="expression"></param>
/// <param name="precision"></param>
/// <param name="datafields"></param>
/// <returns></returns>
public double Calculate(string expression, int precision, List <DataFieldResult> datafields)
{
var filledExpression = expression;
if (string.IsNullOrEmpty(filledExpression) == false)
{
foreach (var item in datafields)
{
if (item.FieldType == DataFieldType.Currency)
{
filledExpression = filledExpression.Replace("[" + item.Name + "]", MakeCurrencyTextParseableAsFloat(item.Value));
}
else
{
filledExpression = filledExpression.Replace("[" + item.Name + "]", item.Value.Replace(',', '.').Replace(" ", string.Empty).Replace("'", string.Empty));
}
}
var calculator = new XtensibleCalculator();
var linqExpression = calculator.ParseExpression(filledExpression);
var linqFunction = linqExpression.Compile();
var retVal = linqFunction();
if (precision >= 0)
{
retVal = Math.Round(retVal, precision);
}
return(retVal);
}
else
{
return(0);
}
}
static void Main(string[] args)
{
var calc = new XtensibleCalculator()
.RegisterFunction("Multiply", (a, b, c) => a * b * c)
.RegisterFunction("MultiplySquare", "Multiply(a, b, c) * Multiply(a, b, c)", "a", "b", "c");
var func = calc.ParseExpression("Multiply(x, y, PI)", x => 2, y => 2 + 3).Compile();
var product = calc.ParseExpression("MultiplySquare(a, b, c)",
new Dictionary <string, double> {
{ "a", 1 }, { "b", 2 }, { "c", 3 }
}).Compile();
Console.WriteLine($"Multiply: {func()}");
Console.WriteLine($"Product: {product()}");
Console.ReadKey();
}
static void Main(string[] args)
{
var calc = new XtensibleCalculator()
.RegisterFunction("Multiply", (a, b, c) => a * b * c);
var func = calc.ParseExpression("Multiply(x, y, PI)", x => 2, y => 2 + 3).Compile();
Console.WriteLine("Result: {0}", func());
Console.ReadKey();
}
public string EvalStringWithVars(string input, Dictionary <string, double> vars)
{
// HACK
var newVars = new Dictionary <string, double>();
foreach (var item in vars)
{
newVars[item.Key.Replace("_", "SUPER")] = item.Value;
}
var newInput = input.Replace("_", "SUPER").Replace("'", "");
var normalInput = NormalizeCommas(newInput);
var expr = calc.ParseExpression(normalInput, newVars);
var func = expr.Compile();
return(func().ToString(CultureInfo.InvariantCulture).Replace("NaN", "error"));
}
