calculator-lib
v1.1.1
Published
Calculate infix / postfix expressions
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Calculator lib
Provides functions for evaluating infix (and RPN postfix) expressions, in JavaScript.
Source is in ES6, released as ES5. Transpiled using Babel.
Installation:
npm install calculator-lib
Usage:
Evaluation of infix expressions
const { evaluateInfix } = require('calculator-lib');
evaluateInfix('4 + 5'); // -> 9
evaluateInfix('2+3/(5^-1)*-1.5'); // -> -20.5
Supported operators
Currently, operations are limited to the following:
- Multiplication (
*
) - Division (
/
) - Addition (
+
) - Subtraction (
-
) - Exponentiation (
^
)
Feel free to add more in a pull request! For example, trigonometric operations would come in handy...
Other methods:
Evaluation of (RPN) postfix expressions
const { evaluatePostfix } = require('calculator-lib');
evaluatePostfix('1 2 + 3 +'); // -> 6
evaluatePostfix('21 -3.2 *'); // -> -67.2
Conversion of infix expressions to (RPN) postfix expressions
const { infixToPostfix } = require('calculator-lib');
infixToPostfix('21 ^ 3 * 2 - 10'); // -> '21 3 ^ 2 * 10 -'