实现了简单的四则运算功能，还实现了高级的科学计算功能，而且具有简洁大方的图文外观-To achieve a simple arithmetic functions, but also to achieve the advanced scientific computing and graphics with a simple elegant look

计算器程序的代码，可以做简单的运算等,程序里会有详细的说明如何计算并输出正确的结果-Calculator program code, can do simple arithmetic, etc