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seen Mar 19 '13 at 5:56

Jul
26
awarded  Yearling
Nov
28
awarded  Enlightened
Nov
28
awarded  Nice Answer
Sep
22
awarded  Nice Answer
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awarded  Caucus
Sep
21
awarded  Constituent
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4
awarded  Investor
Jul
29
revised Finding concave hull for separated small clusters
edited body
Jul
29
revised Finding concave hull for separated small clusters
deleted 1 characters in body
Jul
29
answered Finding concave hull for separated small clusters
Jul
27
comment Finding a Concave Hull
@Jay: You know... this is really a separate question. Can you break this out and start a new question? I'll try to give it a shot...
Jul
27
revised Finding a Concave Hull
added 291 characters in body
Jul
27
comment Finding a Concave Hull
@PlatoManiac: I don't see any spikes; what version of Mathematica are you running? (I'm on v8.0.0 myself)
Jul
27
comment Finding a Concave Hull
@Jay: I'm running Mathematica v8.0.0, and I noted that TetGenConvexHull just returns a surface instead of {pts, surface} like your version does. I can't test this, but maybe you could try Show[(Graphics3D[(GraphicsComplex[#1, Polygon[#2]] & ) @@ TetGenConvexHull[#1]] & ) /@ slices] instead of my Show code.
Jul
27
comment Compact Rational Function Fitting
Is it possible to upload some sample data online somewhere, so we can experiment with fitting equations to it?
Jul
27
comment What does “EquationalLogic`FindCounterexample[]” do?
This is what I intended. s[k][k] is the identity function in combinatory logic. Back in the 20s when this stuff was being invented, Schoenfinkle and Church treated function application as left associative. I agree that right associativity makes more sense for Mathematica. If you would like a reference, see Schoenfinkle's Building Blocks of Logic (1924), $\S3$. Note that Schoenfinkle wrote "C" instead of "K".
Jul
27
answered Finding a Concave Hull
Jul
27
awarded  Supporter
Jul
27
comment What does “EquationalLogic`FindCounterexample[]” do?
@R.M - Thanks. @ in Mathematica are right-associative, which is a little different than in combinatory logic and lambda calculus (where function application is left associative). So I fixed that...
Jul
27
revised What does “EquationalLogic`FindCounterexample[]” do?
Fixed a typo, added links, fixed combinator logic proof