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1h
comment Restarting Mathematica causes an animation to fail to run
@Mr.Wizard I think linking them as duplicates seems right. I was confused because it looks like RunnyKine voted to close as a dupe, but there's no close vote. (?)
1h
revised Restarting Mathematica causes an animation to fail to run
added 367 characters in body
1h
answered Restarting Mathematica causes an animation to fail to run
2h
reviewed Close Why does Fourier give a shifted frequency?
2h
comment What is the order of faces on a D20? How can I optimize the order of faces on a D-n?
@DrXenocide You can also upvote an answer you've accepted, which would be the normal thing to do. (Click the triangle above the vote count.)
2h
revised What is the order of faces on a D20? How can I optimize the order of faces on a D-n?
Fixed formatting
2h
revised How to get a uniformly distributed list of points from a B-spline function
Fixed typo, clarified wording
2h
comment How to get a uniformly distributed list of points from a B-spline function
@Kaisey You have asked 13 questions and accepted none of the answers. (Are they all wrong?) You should see a check mark you can click below the vote count. Accepting the best correct answer is the way such answers are marked on the site and an expected way to say "thank you" to those you tried help you.
2h
comment Fluid mechanics problem concerning flow over a wedge
Does my answer solve your problem, or is there some issue?
2h
revised How to fix problems solving for values of BSpline function?
Fixed typo, added clarification
3h
comment a mysterious error in multiple symbolical integration
Under some circumstances, which I cannot explain in this case, Mathematica will use numerical methods in symbolic calculations. In this case, it seems to have to do with having approximate numeric coefficients, 0.5 and a1. If they are changed to exact numbers 1/2 and 1/3, the NIntegrate messages do not appear. (FWIW, M tries to evaluate NIntegrate[a ArcSin[(2 a)/(Sqrt[(a - R)^2 + (z - z1)^2] + Sqrt[(a + R)^2 + (z - z1)^2])] BesselK[0, a/2], {a, 0, ∞}, WorkingPrecision -> 30.9546, AccuracyGoal -> ∞, PrecisionGoal -> 20.9546], which is foolish because R and z are symbols.)
5h
reviewed Close Why is my compiled code slower?
6h
comment Why is my compiled code slower?
@george2079...that is, IdentityMatrix... :) @OP: Note that K has a special use in Mathematica; evaluate ?K to find out.
6h
comment NDSolve fails to solve vector-valued function x'[t] == a . x[t] + u . b
@gpap Thanks! I might have addressed a similar problem in a similar way before, but I haven't found it yet.
6h
revised NDSolve fails to solve vector-valued function x'[t] == a . x[t] + u . b
Minor clarification
8h
comment a mysterious error in multiple symbolical integration
Have you tried it with a1 = 3/10? It might help to indicate specific R, z that give the message.
8h
comment NDSolve fails to solve vector-valued function x'[t] == a . x[t] + u . b
@m0nhawk To clarify, all the terms must be nonzero (at least for me). I think that's why the workaround in my comment works - {a, b, c} are symbolic and not zero.
8h
answered NDSolve fails to solve vector-valued function x'[t] == a . x[t] + u . b
19h
comment Finding a root of a parameterized integral
In V10, NIntegrate[BesselJ[0, x - 1] BesselJ[0, x + 1], {x, 0, Infinity}, Method -> "ExtrapolatingOscillatory"] throws a First::normal message, which I reported. They responded that it was a bug and that the integral is divergent. They said to consider the asymptotic behavior of the Bessel functions at infinity. But it seems to me that ignores the oscillatory behavior. I might have time to investigate later, but I thought you probably had thought about it already.
21h
reviewed Leave Open Change the size of a graphic inside a legend