I am going to implement custom server side validation of numeric user input.

All is what I nee is to be able to feed a formula to the calculator, feed parameters and get the result back.

The formula consist of basic arithmetical operation, for example like this

```
([name1] + [name2] - [name3])*1.5

```

Then it should accept parameters like 

```
calculator.AddParam("name1", 12);

```

And return the result of calculation like

```
var result = calculator.Calculate();

```

Does such libriary exist for .net?