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| age | ||
| visits | member for | 1 year, 3 months |
| seen | 4 hours ago | |
| stats | profile views | 191 |
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May 22 |
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Interpolation and points of non-differentiability Just do dg[x_] = D[g[x], x] and then dg[5] automatically becomes indeterminate... |
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May 22 |
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Optimizing functions taking matrix arguments This isn't a matrix-valued function. It's a function whose arguments are matrices, but the value the function returns is a scalar $p$-value. |
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Apr 3 |
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Plotting data points: Optimizing size and visuals @whuber, kale: I think this solution can suffer from undersampling. For example, if the data has a narrow spike, Plot's adaptive sampling may miss it entirely. |
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Apr 3 |
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Plotting data points: Optimizing size and visuals Well, the horizontal scale is so much larger than the vertical scale in this case that geometric distances are effectively the same as vertical differences here! But you make a great point. One only needs to modify the dist function to return the vertical difference, and then it does the job. |
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Apr 3 |
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Plotting data points: Optimizing size and visuals A standard approach for simplifying a polygonal curve while losing as little detail as possible is called the Douglas-Peucker algorithm. This demonstration by Mark McClure contains a Mathematica implementation. |
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Mar 3 |
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Differentiating space curves Probably I should also replace every Function[s, ...] with Function[s, Evaluate[...]] for performance as VF1 suggested. Or would that have any side effects? |
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Mar 3 |
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Differentiating space curves This computes $\gamma''(s)/\lVert\gamma''(s)\rVert$, which is not the same as the normal. One can see this, for example, on the parabola $(s,s^2,0)$. |
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Mar 3 |
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Differentiating space curves A closer analogue would be multiplyBy2[r]'[s], but that strangely yields a matrix, which is still not what I expected. I guess I see the problem, though I'm still in the dark about why it happens. Should I just avoid using primes on higher-order functions? |
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Mar 2 |
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Differentiating space curves @Artes: I hadn't seen that before. But I'd rather not redefine tangent and normal for every curve I might be interested in. |
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Feb 24 |
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How to make a plot of function over 24 orders of magnitude? As far as I can tell, the asker wants the point $(d, 0.0000697)$ to be visible on the plot, so this does not answer the question. |
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Feb 22 |
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Mystified by inability to find info to do what seems really basic ...I don't understand why you don't put the expressions into multiple input cells? |
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Jan 20 |
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Plotting the frequency spectrum of a data series using Fourier Aliasing. |
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Jan 14 |
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How to get shadows in Graphics3D? Not unless they added it in the last couple of years... |
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Jan 13 |
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How to create new “person curve”? Given that the coefficients of $t$ inside the sinusoids are 1, 2, 3, ..., this is probably just the Fourier representation of a parametric curve. I'd guess they manually traced the curve as a polygon, took the discrete Fourier transform, and kept just enough of the lowest-order modes to make the curve look right. See also: Ptolemy and Homer (Simpson). |
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Jan 1 |
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Problem with SphericalPlot3D plotting @chris: Oh, that. Yeah, that makes sense. Silly me. |
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Jan 1 |
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Problem with SphericalPlot3D plotting @chris: Unless the editor is different from the notebook interface, that doesn't work for me. Whether it's an input or output cell, whenever I copy a θ it pastes as \[Theta] outside Mathematica. |
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Jan 1 |
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Problem with SphericalPlot3D plotting Oh well, I pasted them in from Character Map. Hope I didn't make a mistake somewhere. |
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Jan 1 |
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Problem with SphericalPlot3D plotting @Mr.Wizard, I don't think it's a duplicate. That question is about colouring the plot; this one is about parts of the desired plot not showing up at all. Unless there's some subtle property of Mathematica I'm missing that makes these the same thing, which, given that Mathematica is sufficiently complicated, is a possibility I won't dismiss... |
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Jan 1 |
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Problem with SphericalPlot3D plotting Is there an easy way to replace the escaped characters with their Unicode equivalents? I searched on meta but only found rcollyer saying they would do this, but not how to do so. |
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Jan 1 |
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Regionplot with Boole - with more than dimension number of variables Three equations in four variables will give you, generically, a one-dimensional solution space, which will project to a curve in 3D. This looks like it's going to be tricky; certainly RegionPlot3D doesn't do curves. |
