Per Alexandersson
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 Mar 11 comment Reuse symbolic polynomial @JasonB: Ok, I'll go for that then. Was thinking there was a cleaner way to do it , but I guess not. Mar 11 comment Reuse symbolic polynomial @JasonB: Simply substituting. That's exactly what happens. But different params give different polynomials. Mar 11 asked Reuse symbolic polynomial Mar 8 comment Change of basis of polynomials @DanielLichtblau: The problem I have is not really doing the change of basis, I know how to do that, the problem I have is how to package it in a user-friendly manner that also allows for efficient memoization. Mar 8 asked Change of basis of polynomials Feb 26 comment Solving large linear systems of equations efficiently? @Kagaratsch: it just reminded me of a problem i had with similar complexity.. Feb 25 comment Solving large linear systems of equations efficiently? What are you doing exactly? Computing structure constants for different bases in representation theory? Feb 11 awarded Yearling Feb 5 answered How to generate two group of $n$ random numbers in $U(0,1)$ such that sum of these two groups equal? Feb 5 comment How to generate two group of $n$ random numbers in $U(0,1)$ such that sum of these two groups equal? @Szabolcs: Well, they CAN both be uniformly distributed and equal, taking $u_i=v_{\pi(i)}$, for some permutation $\pi$, but then they are of course not independent. Dec 1 comment Is Mathematica worth it for me? I started with Mathematica when I was 13. However, a Ti-83 will be more useful, I got one around that time, and that is how I learned programming and more math. Nov 19 comment Refining subset relations @AntonAntonov: You are right! That's a nice interpretation.. well, then this also means that the problem is NP-hard... Nov 18 comment Refining subset relations @AntonAntonov: Well, if the input uniquely defines all values, then the column-form output data you have is perfectly fine. But in a more general case, there must be some sort of disjoint set of equations that still span the same relations that was the input... Nov 18 comment Refining subset relations This is really a nice approach! Nov 18 revised Refining subset relations added example Nov 17 revised Refining subset relations added more background Nov 17 comment Refining subset relations Hi Daniel! Yes, the typical input should be that each object gives exactly one value under the (unknown) map. Nov 13 comment Refining subset relations Ah, right! Ok, so I am looking for an efficient implementation, that exploits nice Mathematica constructs. That is, can my code above be improved? For example, my code iterates over the entire set of rules, and compares all pairs more or less. There should be some smarter way to exclude some cases, and/or exploit say singletons whose value is completely known. Nov 13 revised Refining subset relations added 52 characters in body Nov 13 comment Refining subset relations @DanielLichtblau: Consider them as vectors in $R^3$ then.