此多功能计算器具有简单加减乘除运算，求logX,lnX,x的y次方，连续加减

乘除运算，除数为 0 显示错误1："E1"；数据位数超过8位时，显示错误2："E2"；需要保留3位小数时，如果结果的整数部分超过能显示的位数，显示错

误3："E3"等一些功能。 -This multi-function calculator with simple arithmetic operations, seeking logX, y th lnX, x, and successive subtraction

Multiplication and division, the divisor is　0　error 1: "E1"　over 8 data bits, error 2: "E2"　when the need to retain three decimal places, if the integer part of the result exceeds the number of bits that can be displayed display error

Error 3: "E3" and some other functions.