npm install --save eval-num-expr
import evalExpr from "eval-num-expr"; const value = evalExpr("100 + 3 * 55 + 73 - 73 * 18%"); // value = 324.86 // With Invalid Expressions handling try { const value = evalExpr("100 + (3 * 55"); } catch (e) { // Will throw an exception for invalid expressions console.error(e.message); }
You can use basic operations (e.g. +, -, *, /, %, ^ etc.) in you expressions.
- 175 + 40 + 18% = 253.7
- 10 + (100 - 100 * 18%) * 5 + 40 / 20 = 422
NOTE: Floating points must be handled carefully. Use
Number(<number>).toFixed(<digits>)to fix the digits after decimal point.
This package supports TypeScript.
This is the default and only export from this package.
/** * Evaluate numeric mathematical expression * @param string expression - The expression to evaluate ("24 + 65 * 3 - 48") * @return number - The evaluated value. * * @throws Will throw an error if the expression in invalid. * * NOTE: When passing floating points, please handle the digits after decimal point * e.g. 2 - 1.1 leads to 0.8999999999999999 intead of .9 */ evalExpr(expressions: string)