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Apr
9
comment Make a “ditch” function for electric field purpose
How about just replacing the summation with an integral? Integrate[1/Sqrt[x^2 + (y + t)^2], {t, -5, 5}, Assumptions -> {x, y} \[Element] Reals]
Apr
9
comment Winkel Tripel and Robinson Projections?
Thanks for posting the answer. I have not used WorldPlot or CountryData before so I was not confident that I was interpreting the question correctly.
Apr
9
comment Winkel Tripel and Robinson Projections?
It seems WorldPlot is obsolete. Try CountryData, i.e. CountryData["World", {"Shape", projection}] where projection is "WinkelTripel" or "Robinson".
Apr
9
reviewed Close Entering a system of differential equations
Apr
9
awarded  Custodian
Apr
9
reviewed Close Inverse modulo function
Apr
8
revised Plotting Fourier spectrum versus frequency of a signal
fixed link to `Fourier`
Apr
8
comment Plotting Fourier spectrum versus frequency of a signal
As @bobthechemist's answer shows, you should just use Fourier instead of FourierDCT or FourierDST, and then you don't have to worry about sines and cosines. I mean, just replace FourierDCT with Fourier in the plot in your question and you get the sharp peak you want.
Apr
8
revised Smoothing ListContourPlot contours
added 16 characters in body
Apr
8
revised Smoothing ListContourPlot contours
replaced with LOESS solution
Apr
7
comment Problem with Plot and ParametricNDSolve
You have a few unbalanced parentheses in your first code block, and you need to group the first two equations with curly braces in your ParametricNDSolve. After fixing these errors, I can't reproduce your problem: evaluating nsplot[U3, 4, 40] gives me {1.00743 + 0. I} while evaluating the Table gives {{1.01355 + 0. I}, {1.00743 + 0. I}, {1.0038 + 0. I}, {1.00189 + 0. I}, {1.00093 + 0. I}}. Maybe you have some conflicting definitions left over; try restarting the kernel and evaluating the relevant bits again?
Apr
7
comment plotting 3D function
It seems you had the same problem with your last question; @Sektor had to edit it for you. Can you see the difference?
Apr
7
comment plotting 3D function
Please don't put your code in LaTeX format. Just copy it from Mathematica (not "Copy as LaTeX", just "Copy") and paste it into your question. If you look at literally any other question on this site, like this one which is at the top of the front page right now, you will see it is supposed to look like.
Apr
7
comment Smoothing ListContourPlot contours
I guess the main issue is that your toy example is uniformly sampled, while your real data is very far from it (see ListPlot[Most /@ data, AspectRatio -> 1]: i.stack.imgur.com/DgAAh.png vs. i.stack.imgur.com/zfE5C.png). Also, the aspect ratio of the data is very different from the way you're plotting it.
Apr
7
revised Smoothing ListContourPlot contours
added 64 characters in body
Apr
7
revised Smoothing ListContourPlot contours
deleted 8 characters in body
Apr
7
revised Smoothing ListContourPlot contours
added 17 characters in body
Apr
7
answered Smoothing ListContourPlot contours
Apr
7
comment Sketch-type graphics with transparency and dashed hidden lines?
@Silvia: Thanks! I had a similar idea and tried using FindCurvePoints, but it failed to join up the contours completely. To see this, set oversample = 1 and thickness = 1 and try ListCurvePathPlot[Position[ImageData[edges], 1]]. Any suggestions?
Apr
6
revised Sketch-type graphics with transparency and dashed hidden lines?
added 77 characters in body