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Sep
10
comment How to obtain the GIF by Mathematica?
Usually we discourage "GimmeTehCodez" questions. See the meta post here. There are exceptions but they should be rare.
Sep
9
comment Changing the default font size
Wouldn't it be better to set a magnification factor for the current notebook (at the bottom right of the window) or all notebooks (via NotebookOptions>Display Options> Magnification)? I do that on a computer with a large high-resolution screen where the default also looks too small compared to other screens that I use. By setting magnification, at least the notebook remains portable between computers with different displays (only the magnification has to be adjusted, plots don't need to be re-done).
Sep
8
comment How can one use differential boundary conditions with helmholzSolve?
This should be a comment underneath the answer here.
Sep
8
comment How to create a block diagonal matrix by repeating a submatrix $n$ times?
I posted basically the same thing here, but unfortunately the thread got closed.
Sep
8
comment Should eigenvalues be ordered?
Agreed about the sorting bug. I added my version of JordanDecomposition just for completeness. In fact, thinking of that decomposition, it occurred to me that sorting by absolute value as Mathematica does could be more natural when testing convergence of matrix power series... but it's not a 100% justification.
Sep
8
comment Should eigenvalues be ordered?
In principle my approach should also work for JordanDecomposition, but I have to verify how the latter orders its Jordan blocks under different conditions. This may be an advantage of my approach, in that it doesn't need different sorting strategies for different normal forms.
Sep
8
comment Should eigenvalues be ordered?
@ybeltukov Yes indeed, this is very nice and captures the spirit of what Igor was suggesting (+1).
Sep
8
comment Should eigenvalues be ordered?
@IgorRivin Yes - it certainly shouldn't fail without warning in your approach. Maybe it's a memory issue.
Sep
8
comment Should eigenvalues be ordered?
I agree this question is different from the one I linked, so I decided to re-use my answer here.
Sep
8
comment Should eigenvalues be ordered?
I checked the timings for the example from the linked question. See my update.
Sep
8
comment Find the eigenvector associated with the smallest eigenvalue, not smallest in magnitude
For the problem in this question, sorting the eigenvalues after the fact would be prohibitively slow.
Sep
8
comment Should eigenvalues be ordered?
Don't you think this question should actually be entirely moved to the thread I linked? Of course I could also repeat my answer from there right here, but I don't think that's the right way to do it.
Sep
8
comment Should eigenvalues be ordered?
Closely related: Find the eigenvector associated with the smallest eigenvalue, not smallest in magnitude
Sep
7
comment How to “Copy as Unicode” from a Notebook?
Great - I see no problems on Mac OS X 10.7.5 with Mathematica 10.
Sep
7
comment Evaluating $n$-th derivative of a function at a given point
possible duplicate of Nothing appears in simple plot
Sep
7
comment Problem solving a Fredholm integral equation
this should be a comment underneath the answer you cited.
Sep
7
comment How to use Assuming and If together?
@ppp I noticed you never accepted any answer to your previous questions. Maybe you would get more responses if you checked "Accept" on some of the earlier answers that you apparently liked.
Sep
7
comment Solving Coulomb Integral
This question appears to be off-topic because it is likely about an integral resulting from an ill-posed problem.
Sep
7
comment Hypergeometric function with a matrix argument
@Hirek, do you have any feedback for the answers that have been added to this thread?
Sep
6
comment Solving Coulomb Integral
Without further info, this should be closed as too localized because it's probably based on a faulty starting point.