How do I parse and evaluate a mathematical expression in a string (e.g. '1+1') without invoking eval(string) to yield its numerical value? With that example, I want the function to accept '1+1' and return 2.

May 11, 2016 · One way would be to simply loop over the string and check hasOwnProperty on your math_it_up object for each element; if it's true, call it with the preceding and succeeding indices in the array as the arguments to the function.

Feb 27, 2018 · Here's a regex that can do what I think you're looking for: https://regex101.com/r/w74GSk/4. It matches a number, optionally negative, with an optional decimal number followed by zero or more operator/number pairs. It also allows for whitespace between numbers and operators. console.log("%s is valid? %s", s, re.test(s));

Nov 21, 2020 · Learn how to evaluate a string as a mathematical expression in JavaScript with this comprehensive guide.

Oct 23, 2021 · In this article, you will learn how to write a calculator using Javascript that can evaluate elementary arithmetic expressions. For example 2 * (2+3 / (3 -8)).

Introduction: In this article I am going to explain how to evaluate/ calculate a string expression as a mathematical expression using jquery/Javascript’s eval () function.

Oct 10, 2020 · Let us start with a brief on strings in JavaScript. Then in the next section, we will see the relationship of strings with the most common mathematical operators.

Apr 2, 2022 · When you build a parser, it will recognize which parts of the input string denote operators and which don't. Once the operator tokens are isolated, you can use a simple object to translate them into what they are supposed to do. { "+": (a, b) => a + b, "-": (a, b) => a - b, "*": (a, b) => a * b, /* and so on and so forth... */ }

Nov 4, 2016 · I'd recommend using a library such as Math.js as this will parse the math expression using a regular expression. This will avoid opening the application up to Cross-site scripting (XSS) attacks. minor thing here: Under the covers math.js uses Function().

Nov 23, 2024 · Here is how you can use it to evaluate a string expression: const math = require('mathjs'); let expression = 'sin(45 deg) ^ 2'; let result = math.evaluate(expression); …