Parser And Evaluator Of Mathematical Expression

=========

• Check correctness of mathematical expressions in infix (OK), prefix and postfix notation (WIP)
• Tokenise the mathematical expression (Done only for basic operations, and single argument functions)
• Parse the mathematical expression (Done only for basic operations and single argument functions)
• Evaluates the mathematical expressions (Ok, correct even with functions - eventually with bigNum implementation) (In future with literal calculus)
• Basic GUI for calculator (only basic operations and single argument functions)
• Symbolic Parsing And Evaluating (Not Literal Calculus YET)

======== TO DO

• Add definition of multiargument functions: -log_b (a, x) calculates log x in base a -sqrt_b (n, x) calculates general radicals, not only with 1/2 as exponent
• Add trigonometric and hyperbolic functions not implememted in Java.Math (series expansion or external library)
• Add tokenisation of mathematical functions with more than one argument
• Add parsing of mathematical functions with more than one argument
• Add direct tokenisation of prefix and postfix notation
• Add direct parsing of prefix and postfix notation
• Improve GUI
• Add rational and complex number (Maybe revise whole number system in the application)
• Add misc functions:
  • average
  • fib (iterative method, with arrayList as dataStructure)
  • bynomial_factor (try different implementation)