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2d
comment Hypergeometric function with a matrix argument
Is there a reason why a diagonalization approach doesn't work? Please provide some code with a minimal example.
2d
comment How to evaluate integrals over matrices
Without more information it's hard to answer. What are the matrices A (examples, properties?), and what do we know about the integration measure? What does the integrand look like?
Aug
30
answered Plotting spherical surfaces
Aug
30
comment Hypergeometric function with a matrix argument
I didn't look at the links, but if your matrix is diagonalizable you can apply the scalar function to the eigenvalues and transform the result back afterwards.
Aug
30
comment Plotting spherical surfaces
Are you asking how to fit an ellipsoid to a set of data points? Have you tried Sphere[]? How are the data points really generated?
Aug
30
answered Is undocumented \.bd = ½ bad to use?
Aug
30
comment Can Mathematica solve 625 linear coupled differential equations?
If your Liouville equation leads to a linear system of differential equations with constant coefficients, then the Hamiltonian must be time-independent. This leads to what @Stephen Luttrell was pointing out above. It should be no problem to solve this with NDSolve, provided you specify all the initial conditions. But it can also be done analytically - however, if you want that, you should probably not introduce machine-precision constants into the equation as is done in the code snippet. I can't tell where exactly your problem lies.
Aug
30
answered Menu item “Interrupt Evaluation…” missing in V10
Aug
30
comment Menu item “Interrupt Evaluation…” missing in V10
Maybe you can instead turn on Evaluation > Debugger and use the Halt and Continue buttons?
Aug
30
comment Integral of x^p
I think the answer to this question has been given here.
Aug
29
comment How to display movie without controls
Perhaps you can use the example in my answer here.
Aug
29
awarded  Excavator
Aug
29
comment How to simplify the integration result of the following program?
I edited your answer to add a fix for version 10 that I also used in the answer you linked to.
Aug
29
revised How to simplify the integration result of the following program?
Added NumericFunction attribute to antiderivative to make it work in version 10
Aug
29
revised how to simplify symbolic integration
Added NumericFunction
Aug
29
comment how to simplify symbolic integration
@Picket I've submitted a bug report[CASE:1477670], but I figured out a fix, see my edit.
Aug
29
reviewed Close Overlay 3d plots in Manipulate
Aug
29
reviewed Close What are the upper bound and stability conditions for the following simple linear system
Aug
29
comment how to simplify symbolic integration
@Pickett Thanks for letting me know, anyway - maybe I'll report it as a bug - finding out that old code no longer works seems one of the constant battles in Mathematica. But I've had worse (recalling version 5 -> 6 and then again 6 -> 7)...
Aug
29
comment how to simplify symbolic integration
@Pickett It definitely works in version 8 which I still use for serious work. Version 10 seems to be mainly thrown out there to get a lot of free beta testers. But I'll look into it later.