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vessenesyesterday at 3:58 PM2 repliesview on HN

It's improperly formed as a question - the ruffian can shoot whenever he likes;

Consider:

Does "random" mean

1. uniform distribution on x and y coordinates with some sort of capping at the circle boundary? Or perhaps uniform across all possible x,y pairs inside (on the edge also?) of the circle? what about a normal distribution?

2. a choice of an angle and a length?

3. A point using 1 or 2, and then a random walk for 2 and 3?

I could go on. The worked solution is for random = uniform distribution across all possible reals inside the boundary, I think.


Replies

szczepan1yesterday at 4:19 PM

Author here: when calculating this I _did_ assume a uniform (area) distribution on the unit disk.

Now it does say

> Three points are chosen independently and uniformly at random from the interior of a unit circle.

which sounded OK to me at the time but I understand there could have been some ambiguity. Especially around the "uniform on area" part.

Also, I think that with rejection sampling you could get the same with 1) [0], 2) would work (provided correct scaling) [1]. No idea about 3) or the normal distribution thing you mentioned - I figured the problem was hairy enough already!

[0] https://blog.szczepan.org/blog/monte-carlo/#sampling-uniform... [1] https://blog.szczepan.org/blog/monte-carlo/

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voidmainyesterday at 4:17 PM

The article currently says

> Three points are chosen independently and uniformly at random from the interior of a unit circle

Has it been edited in the last 15 minutes to address your objection or something?

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