Add Convex Hull JavaScript

[GriffinAnnshual]

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I Am Adding a New Code Snippet in an Existing Language

• I fixed Add Convex Hull in Javascript #3354
• I named the pull request using Add {PROJECT} in {LANGUAGE} format

[rzuckerm]

Looks like you have several test failures to address. One of these is the error message, which should be this:

Usage: please provide at least 3 x and y coordinates as separate lists (e.g. "100, 440, 210")

[rzuckerm]

@GriffinAnnshual I'll give you hint as to a problem with your implementation. You missing a key first step. See this for details.

[GriffinAnnshual]

@rzuckerm Bro where is the mistake is it in the implementation or on the test cases? Could you please help?

[rzuckerm]

@rzuckerm Bro where is the mistake is it in the implementation or on the test cases? Could you please help?

The mistake in the implementation is that the first point is used to calculate the angles. According to this, the point with the lowest y-coordinate is supposed to be used:

find the lowest y-coordinate and leftmost point, called P0
sort points by polar angle with P0, if several points have the same polar angle then only keep the farthest

The test case that is failing called called "Sample Input Pentagon" in this.

[GriffinAnnshual]

Okay got it.. I will work on it.

[rzuckerm]

Since this is the last day of Hacktoberfest, I went ahead and fixed this sample since it was pretty close to working.