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Malipeddi

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There are other quite elegent methods for triangle and simplices.

For a triangle, drawing α and β uniform over [0,1) the barycentric coordinates given by (1-sqrt(α), sqrt(alpha)(1-β), βsqrt(alpha)) is uniform over the triangle. No rejection and no test for flipping.

For simplices (triangle, tetrahedron, 5-cell etc) barycentric coordinates obtained by drawing uniformly from (0,1] taking a log and normalizing will be uniform within the simplex.

I wrote about this and other related sampling below.

https://abhila.sh/writing/5/Random_Sampling.html

https://abhila.sh/writing/8/Random_Sampling_2.html

This is a neat and accessible introduction to the topic. Nice work! I want to mention nesting quadratures like Gauss-Kronod like Clenshaw-Curtis/Fejér. The nesting means that the quadrature points for lower order are included in the points required for higher orders. This allows you to increase your order of accuracy if required with fewer total evaluations.

I'm a computational physicist (PhD, Mechanical & Aerospace Engineering) and postdoc at UofM, researching high-performance algorithms for multiscale, multiphysics phenomena. I co-develop Crimson (www.crimson.software), a blood flow simulation tool for vascular research and surgical planning. Skilled in high-performance computing, optimization, and novel computational methods, I also consult extensively within and beyond my research group. Transitioning from academia to industry, I seek roles in applied research, computational engineering, or software development tackling open-ended problems.

Location: Anywhere in US

Remote: Open to remote.

Willing to Relocate: Yes

Technologies: C++, Fortran, Python, HPC stack; experienced with Docker deployments, GPU computing, and modern infrastructure strategy.

Resume/CV: https://abhila.sh

Email: absh [at] umich.edu

Related write-ups below along with comparison of performance of different approaches. BMI2 instruction set based method seems to be the fastest of the lot.

1. https://www.forceflow.be/2013/10/07/morton-encodingdecoding-...

2. https://www.forceflow.be/2016/01/18/libmorton-a-library-for-...

3. https://github.com/Forceflow/libmorton

I used it to accelerate nearest neighbor detection for collision processing in particle-laden flow for modeling complicated domains in 3d (for biological fluids simulation). I was using it as a locality sensitive hashing to put particles near each other in the same bucket in an hash map. I came across the ideas of BIGMIN (big minimum) and LITMAX (little maximum) for range search in a morton encoded data that I found to be cool.