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Feb
7
revised Can a LatticeData image be displayed in a space filled fashion
Added workaround
Feb
7
comment How to numerically solve a 1-d time-independent Schrodinger equation?
I think it's easiest to do that kind of normalization with an $r$ integral directly, then you won't need any Jacobian factors. But of course you'll get problems when the high-lying states aren't spatially resolved, as I already said. If you want such states to be represented more accurately, you'll have to modify either MaxCellMeasure or the transformation of variables. Maybe I'll write some more tomorrow.
Feb
6
comment MatrixForm in Mathematica
See in particular point 8 in this post
Feb
6
revised how to generate a 3d graph of HCP crystal structure
Added workaround
Feb
6
comment how to generate a 3d graph of HCP crystal structure
added bug tag because of the previous post that's now linked in the question. It's probably OK to have this question for reference.
Feb
6
revised how to generate a 3d graph of HCP crystal structure
Edit to make bug reproducible; edited tags
Feb
6
comment how to generate a 3d graph of HCP crystal structure
This could be made into a valid question by adding the code to reproduce it. I'll just do that because I already did it before...
Feb
6
answered how to generate a 3d graph of HCP crystal structure
Feb
6
comment NDeigensystem returns complex non-hermitian error for the calculation of vibrations of a cantilever
Looks like you made exactly the same error as in the link I posted above.
Feb
6
comment NDeigensystem returns complex non-hermitian error for the calculation of vibrations of a cantilever
Closely related: NDEigensystem producing imaginary eigenfrequencies for the vibrations of a cantilever.
Feb
6
comment Fourier-style solutions to differential equations, not piecewise polynomials
@Nasser is right, and I think the question is not specific enough. E.g., what are the boundary/initial conditions? We would need a minimal example to work with. Maybe one can rewrite the whole equation in Fourier space, but that depends on the details. If the spectrum is continuous, you won't gain anything in terms of simplicity of the output, I think.
Feb
6
comment How to numerically solve a 1-d time-independent Schrodinger equation?
If you don't have analytic comparison functions, then there is nothing to compare to, right? So there's nothing to do, since the eigenfunctions in NDEigensystem are already normalized by default. If you're asking about something else, it's better to start a new question.
Feb
6
revised Use of some functions of the Developer Utility Package, such as BesselSimplify
Example has no initial simplification.
Feb
5
comment Generation of Space Representation of non-crystallographic Point Groups
I could do it for 2D (since we know where the polygon vertices are), but I think you're asking more generally about 3D... and I don't have a good general answer for that.
Feb
5
comment How to numerically solve a 1-d time-independent Schrodinger equation?
I just used the $r\to 0$ limit because at random other points you could accidentally get a divide-by-zero error when doing the normalization the way I did. Integrating to normalize seems way too costly for simple comparisons, but it's certainly an option. The eigenfunctions near zero energy do become very oscillatory in the transformed variable, so both NDEigensystem and NIntegrate will need a lot of points to get things right.
Feb
5
comment General function for the expansion of a polynomial of operators
You probably meant this as a comment to my answer, but accidentally posted it in a new answer box. Thanks for the suggestion, anyway...
Feb
5
comment Generation of Space Representation of non-crystallographic Point Groups
Not an answer, but there is a way to get non-crystallographic point groups with the command DihedralGroup... e.g., DihedralGroup[7]//GroupElements gives you the permutation representation which can be then converted to real space. For other points groups, I guess one would first have to figure out if they're isomorphic to some DihedralGroup[n]. I guess that's a partial answer, but maybe not what you're looking for.
Feb
4
comment Color a single contour from a ListContourPlot3D using values from a list
@JasonB Since you put in all the work already, I'll vote to re-open, too...
Feb
4
revised How to numerically solve a 1-d time-independent Schrodinger equation?
Comparison with exact results
Feb
4
answered Use of some functions of the Developer Utility Package, such as BesselSimplify