A complex calculation kernel in Java (for Calci calculator)

These are complex-number classes to implement complex calculation.
The content of each class is as follows:

• Complex.java: Contains a complex number, implemented complex number display (toString method) and some basic complex functions
• Expression.java: Expression parser and expressional functions (such as diff, integ, fzero & so on)
• Result.java: Contains a complex result and error codes
• Function.java: Function names and serials used in Expression.java is registrated in this class
• ParseNumber.java: Number parser for different radixes
• TestMain.java: A sample to test this package

Files are encoded in UTF8. Class Complex, Result & ParseNumber must be used together. Class Expression & Function may separate.

The simplest way to parse an expression and calculate its value is:

Expression expr = new Expression(string);
System.out.println(expr.value().val);

Parsable string examples:

-3*(6+2.5)/4E2-.7*-1.01π
fzero(x^2-x-1,1)
sqrt(4+i)/arctan(-2i-1.1)^i

An Android app using this kernel (Calci_X.X.X.apk) is provided.
The present package is used in Calci 1.3.3.