Simplifying and evaluating mathematical strings [closed]

问题

Closed. This question needs to be more focused. It is not currently accepting answers.

---

Want to improve this question? Update the question so it focuses on one problem only by editing this post.

Closed 14 days ago.

What would be the simplest way to evaluate/simplify a mathematical string in VB?

For example: "k*k+(5+2*5)k+k" would simplify to "k^2+15k+k" and "5^2+3" would evaluate to 28.

To evaluate, I'm using NCalc by simply using the evaluate function, but it doesn't simplify expressions. What would be the simplest way of simplifying the equations?

回答1:

You could try Math.NET Symbolics.

It doesn't "know" about the implied multiplication for (a)b, so you would have to work out how to insert an * if you can't require it.

Imports MathNet.Symbolics
Imports Expr = MathNet.Symbolics.SymbolicExpression

Module Module1

    Sub Main()
        Dim a = Expr.Parse("k*k+(5+2*5)*k+k")
        Console.WriteLine(a.ToString())
        Console.WriteLine(Expr.Parse("5^2+3"))

        Console.ReadLine()

    End Sub

End Module

Outputs:

16*k + k^2
28

来源：https://stackoverflow.com/questions/59444338/simplifying-and-evaluating-mathematical-strings