[Snippets] Added several new mathematical snippets for JavaScript.

[JanluOfficial]

Description

Added a bunch of snippets regarding math functions in JavaScript. These include the following:

• Combinations, which calculate the number of combinations (denoted as C(n,r) or "n choose r"), which determines how many ways you can select r items from n items without considering the order.
• Cross Product, which computes the cross product of two 3D vectors, which results in a vector perpendicular to both.
• Dot Product, which computes the dot product of two vectors, which is the sum of the products of corresponding elements.
• Error function, which computes the error function (erf(x)) for a given input x, which is a mathematical function used frequently in probability, statistics, and partial differential equations.
• Least common multiple, which computes the least common multiple (LCM) of two numbers 𝑎 and b. The LCM is the smallest positive integer that is divisible by both a and b.
• Matrix Multiplication, which multiplies two matrices, where the number of columns in the first matrix equals the number of rows in the second.
• Modular Inverse, which computes the modular multiplicative inverse of a number a under modulo m, which is the integer x such that (a*x) mod m=1.
• Prime Number, which checks that the number is a prime number.
  I also updated the tags for greatest common divisor, which I added as a snippet in [Snippet] Added code snippet for Greatest Common Divisor in JS #170 .

Type of Change

• ✨ New snippets
• 🛠 Improvement to an existing snippet
• 🐞 Bug fix
• 📖 Documentation update
• 🔧 Other (please describe):

Checklist

• I have tested my code and verified it works as expected.
• My code follows the style and contribution guidelines of this project.
• Comments are added where necessary for clarity.
• Documentation has been updated (if applicable).
• There are no new warnings or errors from my changes.

Related Issues

None

Additional Context

I let ChatGPT help me with explaining and occasionally writing the JavaScript required for these snippets, but I double checked that everything works using node.js, as well as on a about:blank page in the DevTools of Microsoft Edge.

Screenshots (Optional)

Click to view screenshots

[Mathys-Gasnier]

For me it looks good, but i'm not a math guy myself, so let's wait on another review and I think we will be good

[JanluOfficial]

@Mathys-Gasnier You can ask ChatGPT if none of the other reviewers know this math. Wouldn't expect anyone to understand it anyways.

[psychlone77]

Also, almost all of these functions are available in the mathjs library, So, maybe include how to perform the same calculation using that library as well. I like these snippets, but anyone who wants to do a lot of complex calculations like erf might be better of using the library. @Mathys-Gasnier.

[Mathys-Gasnier]

IMO we shouldn't take into account external dependencies when deciding if snippets should be added, the reason being that some people don't like adding lots of deps to their project (which is a good thing seeing how NPM packages keep failing in the last couple of years)

[JanluOfficial]

IMO we shouldn't take into account external dependencies when deciding if snippets should be added, the reason being that some people don't like adding lots of deps to their project (which is a good thing seeing how NPM packages keep failing in the last couple of years)

I agree with Mathys, since I personally don't like bloating up my projects with random packages. Aside from that, I also intended for people to be able to just copy and paste them into a website that is made only with HTML, CSS and bare bones JS, no node.js and npm stuff. That said, if a separate "Node.js" language category is added, I may add snippets on how to use mathjs for those.

[psychlone77]

Changes look good. I too now agree on the package bloating 🫡 .
Finally, thank you for your contribution to the project @JanluOfficial.

[JanluOfficial]

You're welcome @psychlone77
I intend to keep contributing in the future, unless I get hospitalized or something.