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Jul
19
awarded  Nice Answer
Jul
19
answered Detect each polygons in an image
Jul
19
awarded  Cleanup
Jul
19
revised How can I extract the outline of bubbles in my image?
rolled back to a previous revision
Jul
19
revised How can I extract the outline of bubbles in my image?
deleted 37 characters in body
Jul
19
answered How can I extract the outline of bubbles in my image?
Jul
18
comment Harmonious graph labeling
@rm-rf: Apparently this.
Jul
18
comment Opacity limitations?
Why not just ParametricPlot3D[{Cos[lat] Cos[lon], Cos[lat] Sin[lon], Sin[lat]}, {lat, -Pi/2, Pi/2}, {lon, -Pi, Pi}, PlotStyle -> {Opacity[0.7], White}, MeshStyle -> Black]? i.stack.imgur.com/pPKE6.png
Jul
17
comment What is the right way to write a function that includes other functions?
Now that you've clarified the question: You're overcomplicating this! You can just write it the way you wrote it in math: b[x_] := 10 x; w[x_] := s + b[x]; c[x_] := x^2; u[x_] := w[x] - c[x]
Jul
16
revised how to create a slope field in mathematica?
edited tags
Jul
16
comment Issue with PieChart3D in Version10. Is it Mac specific?
I'm running Mathematica 10 on Mac OS X 10.9.4 (64-bit) and I'm afraid I do not see this problem...
Jul
16
comment Does FindFit support complex numbers or doesn't it?
@seismatica: In principle it is equivalent to minimize the total squared error or the square root of it, because the square root function is monotonic. However, from a numerical optimization perspective, it is better to minimize the total squared error directly, because it is smooth, quadratic, and generally well-behaved, while its square root is not as nice. That might be why the fitting is slow to converge when the square root is taken.
Jul
15
comment Infinite expression encountered when simplifying ArcTan sums although the result is finite
For what it's worth, the value of $\tan^{-1}x+\tan^{-1}(1/x)$ is not simply $\pi/2$ but $\begin{cases}\pi/2&\text{if $x>0$}\\-\pi/2&\text{if $x<0$}\end{cases}$
Jul
15
comment Fitting fractional complex data with NonlinearModelfit
Here's why NonlinearModelFit on complex data sometimes works and sometimes doesn't: mathematica.stackexchange.com/a/54876/484
Jul
15
comment Does FindFit support complex numbers or doesn't it?
@seismatica, halirutan: NormFunction -> (Re[#].Re[#] + Im[#].Im[#] &) seems to work better.
Jul
15
comment Does FindFit support complex numbers or doesn't it?
@Alexey: Ah, thanks for the link. I hadn't looked at that question carefully before; it does look like a duplicate. Although none of the answers there have realized why FindFit works in some cases but not in others, as Jens's answer here explains.
Jul
15
accepted Does FindFit support complex numbers or doesn't it?
Jul
15
comment Does FindFit support complex numbers or doesn't it?
The strangeness is that FindFit can determine the appropriate norm function in some cases but not in others.
Jul
15
asked Does FindFit support complex numbers or doesn't it?
Jul
15
comment How to make a discretized NMinimize more precise
The first thing I'd try is to increase MaxIterations.