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May
9
comment How do I evaluate several n-th derivatives of a function at one point?
BTW, there is another cool use for this method: to prove that the Dirac delta function is the limit of the sinc function, one can do this: InverseFourierTransform[ Limit[ FourierTransform[Sin[\[Omega] t]/(\[Pi] \[Omega]),\[Omega],\[Tau]], t->\[Infinity]], \[Tau],\[Omega]] (I actually don't know any better way of getting that result in Mathematica because of the conservative way DiracDelta is defined).
May
9
comment How do I evaluate several n-th derivatives of a function at one point?
This does work, but only if the function decays fast enough to infinity. I don't think it will work for any kind of polynomials. E.g., try x^2: you get indeterminate errors (with n=1).
May
8
comment Drawing Cylindrical Segment with Graphics3D
But this doesn't hide the intersecting caps properly at the branch point, which is the main point of the question. You can see this more clearly by increasing the Tube radius in your example.
May
7
comment Dynamically labeling a family of curves
By "dynamically," do you really mean you want to place the labels programmatically based on the coordinates computed in Table? In Mathematica lingo, "dynamic" placement would usually be interpreted as "interactive" manipulation.
May
7
comment Error invoking Information on functions containing Legended
I agree it behaves like a bug. Would you mind adding the bug tag to the question (so I don't get in trouble for doing it myself)?
May
6
comment Error invoking Information on functions containing Legended
Unfortunately, your edited solution doesn't work with my original function. And your first solution (using Unprotect) still doesn't work with the function I defined in this answer which motivated my question. But certainly some kind of UpValues solution will be the way to go, even if it has to be more hand-tuned... so I upvoted this. I'll wait a little more before accepting it.
May
5
comment Error invoking Information on functions containing Legended
@Silvia Interesting observation. I have to add that to my question: the function should first be evaluated to see the error.
May
5
comment rasterListContourPlot With PlotLegends in Mathematica 9
I've changed the code at the URL linked above, so the problem mentioned in the question no longer occurs. If the changes work as I hope, it may be best to close this question as too localized. But I'd suggest waiting a little so I can get feedback.
May
5
comment rasterListContourPlot With PlotLegends in Mathematica 9
The reason my functions don't work with version 9 legends is of course that they were written before version 9. And unfortunately the new legends cause the output of plots to have different Head (Legended instead of Graphics) when you specify a legend. I didn't anticipate this new invention (nor do I think it's a good change). But I'll try to modify my functions eventually. This kind of thing is exactly why I've mainly kept working with version 8 so far. It's too much work to update all my notebooks...
May
4
comment A matrix-vector cross product
@J.M. BTW, a related answer where I used this is: Is it possible to do vector calculus in Mathematica?. Hope you don't get into an identity crisis...
May
1
comment Find points on the surface of a Graphics3D object
I assume you're aware of this, but the vertex coordinates of the original PolyhedronData object are accessible like this: PolyhedronData["GreatStellatedDodecahedron", "VertexCoordinates"] // N
May
1
comment Override Equation structure change in mathematica - CopyToLaTeX
@Rojo Ah, that could be. I'll wait for clarification.
May
1
comment Numerical partial derivative
Related question: How can I differentiate Numerically?
May
1
comment Override Equation structure change in mathematica - CopyToLaTeX
@JonathanShock I understood it differently. The question is explicitly about TeXForm rearranging things. What you mention already happens in StandardForm. If you're right, the question is phrased incorrectly.
Apr
29
comment Exploiting self-adjointness when changing basis
This has also been addressed in the comments and answers to Can Eigenvalues and Eigenvectors be assumed to return the same ordering?
Apr
29
comment Export matrix to $\LaTeX$ with style
A general-purpose way of getting useable $\LaTeX$ code is to Export as PDF, then import into Inkscape and from there choose Save As > LaTeX with PSTricks Macros. That produces a .tex fragment which can go into the body of a host file as long as the latter calls \usepackage{pstricks} first. This isn't specific to tables, it works for anything that can be exported as PDF. For specific things like tables, it's also possible to generate the $\LaTeX$, but only by hand-coding it.
Apr
28
comment Help with 1-dimensional random walk
(+1) But why impress only the girls?
Apr
27
comment Mathematica command for type checking?
You may be interested in this question: Automatically check student answers in tests
Apr
24
comment Animating the Lorenz Equations
For visualization, see also this answer by @kguler.
Apr
23
comment Optimizing a Numerical Laplace Equation Solver
There are so many nice tricks in here... (+1). To make this code easier to study, I think it will be good to add a link to this page: What are some useful, undocumented Mathematica functions?