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 Oct 27 awarded Good Question Oct 14 revised Graph showing valid English words obtained by insertion of single characters formatting Sep 30 awarded Explainer Sep 19 awarded Generalist Sep 15 awarded Nice Question Aug 29 comment Integral of x^p Oh right that's why it doesn't work in mathematica. Oops, pattern recognised the wrong thing, I'm an idiot sorry. Aug 29 comment Integral of x^p Actually the log is recovered in the limit. It's just that mathematica doesn't recover it correctly. Aug 29 comment Integral of x^p Well, $\lim_{p\rightarrow -1} \frac{x^{p+1}}{p+1}=\ln(x)$. Not that mathematica knows this, though (try Limit[x^(1 + p)/(1 + p), p -> -1]) Aug 27 comment Numerical error in Mathieu functions Mathematica doesn't like Mathieu functions Aug 23 comment ToExpression from commandline I think it is a bug, in the sense that eg Plot[Sin[x],{x,-5,5}] doesn't cause mma to hang. So, while I agree that the fact that it fails is not a bug, that it hangs seems to be. Or am I missing something? Aug 22 comment Importing multiple images for machine learning classification something like Import[#] & /@ FileNames["folder/*.jpg"] is what you want. Mathematica has about 3 gigabytes of documentation. Aug 15 comment Finding average error of the data @Mike a) that code doesn't work unless I know temp, b) is it too much to ask what doesn't work with LinearModelFit or the NonlinearModelFit example I gave? Aug 15 comment Finding average error of the data If, for example, dat = Table[{x, Sin[x] + RandomReal[{-.2, .2}]}, {x, 0, 10, .1}]; (because the code you gave needs a location and other parameters and I don't know, nor want to learn, how to set that) then eg mdl = NonlinearModelFit[dat, a*Sin[b*x] + c, {a, b, c}, x] finds a model and you can find for example the variance like so Variance[dat[[All, 2]] - mdl /@ dat[[All, 1]]]. Aug 15 comment Efficient Langevin Equation Solver @chris I don't know to be honest. Why not write to him? Aug 14 comment Test a wooden board's vibration mode @Mr.Wizard OK, as you can see I did not vote for it to be closed. Maybe you're right. Aug 14 comment Test a wooden board's vibration mode @Mr.Wizard Also, it's not that unreasonable to expect that the answer to this could be modified to apply here. Does it? Does it not? Why not? We're not told. Aug 14 comment Test a wooden board's vibration mode @Mr.Wizard I'm not implying that anybody is getting pressured. All I am saying is that this is a question of precisely the same type as the one I posed, which presumably you'd not find good (as it is not well written, not necessarily valuable for future readers unless and not of reasonable scope, as it does not even attempt to express things in programming terms). That is, it does not satisfy 3 of the 4 criteria in the question you linked to. Aug 14 comment Test a wooden board's vibration mode @Mr.Wizard Would you also think that "please show me how to find the ground state of the 2d Kitaev model with Mathematica's linear algebra tools" is of reasonable scope? If not, why not? (in fact, mine is a much, much less technically involved question--unless we do include the spruce bit). Aug 8 comment unlisting a nested list do you mean that you literally have the symbol c and would like to end up with c1 and c2? Aug 8 comment Removing some data and replacing them with new ones In addition to what @RunnyKine said, here's what actually happened: you ask a question that seems to be answered by Differences. Then it turns out what you actually want is a filter to replace data if (roughly) the gradient is higher than some value by some interpolated value. But this is only clear from reading the comments. It would help in getting an answer if you included the info from the comments in the question (maybe with a short version of your data and some rough attempt to do what you want). Basically, imagine you don't know what the question is.