Source and code of polynomial math parser in VB.NET

Source and code for polynomial math parser in VB.NET

This code contains five classes to evaluate a string of a real, complex, or polynomial mathematical expression, perhaps reducing the expression to a real or complex number or an equivalent polynomial. A mathematical expression may or may not contain variables.

Sample runtime images

Introduction

In many situations, string may contain a mathematical expression, such as "1+2*5", "(3+i)(3-i)", or "(z^2*w+4z^3w-w^ 2-4z*w^2)/(w+4z*w)" and there is a need to calculate and calculate the result. Maybe we need to calculate the result for the values ​​of different variables and the result can be another polynomial. In these cases, the polynomial parser provided here may help.

Background

The classes here are a small - but improved - part of my free, downloadable CAS calculator. One of the goals is that these classes do not rely on other "external" classes, as is the case with the CAS calculator.

Seven classes

• The "Msg10" class contains only a few messages to handle possible errors.
• The G10 class contains global members such as Regex patterns.
• "Rational" class gives more precision in operations.
• The "Complex" class performs complex math.
• The "Polynomial" class handles polynomials.
• The "Roots" class finds the roots and factors of polynomials.

"parsePolynomial" class is responsible for dividing the input string into symbols and calling based on it to Roots or Polynomial class of Msg10s. Roots depends on Polynomial class which in turn depends on Complex and Complex on Rational. The "tokenization" work is done by a Regex pattern.