caichaoqing / rpn.js

Reverse Polish Notation tools. Translate infix expression to reverse polish notation (postfix expression) and Calculate reverse polish notation. support + - * / ^ % ! √ ( ). 逆波兰表达式工具，可以把普通表达式转换为逆波兰表达式，还可以计算逆波兰表达式。支持+ - * / ^ % ! √ ( )。

逆波兰表达式工具Reverse Polish Notation tool

1. 介绍Intro

逆波兰表达式工具Reverse polish notation tool, ，普通表达式 和 逆波兰表达式 互相转换 translate between infix expression and reverse polish notation, ，计算 普通表达式 和 逆波兰表达式calculate infix expression and reverse polish notation, ，支持 + - * / ^ % ! √ ( )support + - * / ^ % ! √ ( ).。

可以在浏览器里使用，也可以当作Node的模块使用the tool is both can work in browser and work as a node module.。

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2. 用法Usage

2.1 Node

$npm install jsrpn
$node
> let rpn = require('jsrpn');
> console.log(rpn.calculate('1+2+3+4+5+√√81!'));
21

2.2 Browser

<script src='./rpn.js'></script>

<script>console.log(rpn.calculate('1+2+3+4+5+√√81!')); //21 </script>


3. 接口Interface

3.1 计算算式表达式Calculate infix expression

rpn.calculate(expression)

范例Example

rpn.calculate('1+2+3');
6
rpn.calculate('8!');
40320
rpn.calculate('√81');
9
rpn.calculate('√√81!');
6
rpn.calculate('1+2+3+4+5+√√81!');
21
rpn.calculate('1+2*3+4/5');
7.8
rpn.calculate('1+2^3');
9
rpn.calculate('1%+2^3');
8.01
rpn.calculate('15%+2^3');
8.15

3.2 转换算式表达式为逆波兰表达式Translate infix expression to reverse polish notation

rpn.infix2rpn(expression)

范例Example

rpn.infix2rpn('1+2+3');
"1 2 + 3 +"
rpn.infix2rpn('8!');
"8 !"
rpn.infix2rpn('√81');
"81 √"
rpn.infix2rpn('√√81!');
"81 √ √ !"
rpn.infix2rpn('1+2+3+4+5+√√81!');
"1 2 + 3 + 4 + 5 + 81 √ √ ! +"
rpn.infix2rpn('1+2*3+4/5');
"1 2 3 * + 4 5 / +"
rpn.infix2rpn('1+2^3');
"1 2 3 ^ +"
rpn.infix2rpn('1%+2^3');
"1 % 2 3 ^ +"
rpn.infix2rpn('15%+2^3');
"15 % 2 3 ^ +"

3.3 计算逆波兰表达式Calculate reverse polish notation

rpn.rpnCalculate(expression)

范例Example

rpn.rpnCalculate('1 2 + 3 +');
6
rpn.rpnCalculate('8 !');
40320
rpn.rpnCalculate('81 √');
9
rpn.rpnCalculate('81 √ √ !');
6
rpn.rpnCalculate('1 2 + 3 + 4 + 5 + 81 √ √ ! +');
21
rpn.rpnCalculate('1 2 3 * + 4 5 / +');
7.8
rpn.rpnCalculate('1 2 3 ^ +');
9
rpn.rpnCalculate('1 % 2 3 ^ +');
8.01
rpn.rpnCalculate('15 % 2 3 ^ +');
8.15

3.4 转换逆波兰表达式为算式表达式Translate reverse polish notation to infix expression

rpn.rpn2infix(expression)

范例Example

rpn.rpn2infix('1 2 + 3 +');
"1 + 2 + 3"
rpn.rpn2infix('8 !');
"8!"
rpn.rpn2infix('81 √');
"√81"
rpn.rpn2infix('81 √ √ !');
"√√81!"
rpn.rpn2infix('1 2 + 3 + 4 + 5 + 81 √ √ ! +');
"1 + 2 + 3 + 4 + 5 + √√81!"
rpn.rpn2infix('1 2 3 * + 4 5 / +');
"1 + 2 * 3 + 4 / 5"
rpn.rpn2infix('1 2 3 ^ +');
"1 + 2 ^ 3"
rpn.rpn2infix('1 % 2 3 ^ +');
"1% + 2 ^ 3"
rpn.rpn2infix('15 % 2 3 ^ +');
"15% + 2 ^ 3"

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4. 调试及测试Debug and testing

• mocha
• 如果有全局安装 'mocha' 工具，用命令直接启动测试If 'mocha' already installed as a global tool, use command to start testing
• npm install
• 安装测试工具 mocha 和 测试报告工具 mochawesomeUse this command to install test tool 'mocha' and test report tool 'mochawesome'
• npm test
• 用命令会启动测试，完成后测试报告会显示在浏览器里Use this command to start testing, and the test report will open in browser after test finish.