This is the first parser difference I mention here.

acer

This is the first parser difference I mention here.

acer

It's a bug in the documentation only, I think, that it doesn't describe the nonsymmetric case.

The term "positive definite" refers to what sign the scalar value x^%T.A.x can take on for any nonzero column Vector x, rather than (always) what sign the eigenvalues have. Hence Robert's example below is not a counter-example to match your bracketed/ie description, I think.

Now, some texts state the definition of the term "positive definite" by stating that "A symmetric/hermitian matrix is positive-definite if..." and so of course with that wording the symmetric aspect is built right into the concept. And for a symmetric/hermitian Matrix the positive-definiteness matches whether the eigenvalues are all positive. But the definition needn't be taken as always including the symmetric quality.

Modulo bugs, you ought to be able to rely on IsDefinite for nonsymmetric Matrices.

Having said that, I sort of remember that there was a short-lived (1 release, then fixed, maybe in Maple 12?) glitch introduced in the recent past for the nonsymmetric case. It's Sunday afternoon,... and I hope that I haven't remembered that situation all wrong.

acer

That looks nice. I notice that you had to find an acceptable X (as described above), here based on some extra knowledge about the source.

"..in the car example you might be able to state a range for acceptable width of clusters on the basis of ...[].. and the known car speeds."

acer

That looks nice. I notice that you had to find an acceptable X (as described above), here based on some extra knowledge about the source.

"..in the car example you might be able to state a range for acceptable width of clusters on the basis of ...[].. and the known car speeds."

acer

An uncharacteristic slip. Perhaps Joe meant [{L[]}[]]

;)

acer

An uncharacteristic slip. Perhaps Joe meant [{L[]}[]]

;)

acer

I'm sorry, but I've been very busy with real-life commitments. I haven't forgotten, though. It's "on my list".

acer

I'm sorry, but I've been very busy with real-life commitments. I haven't forgotten, though. It's "on my list".

acer

Those `else` clauses are wrong. Just remove both of them. Then put `return Yes` as the new last line of the proc.

Also, try to follow all the earlier advice about `with` and `uses`. And don't use % inside a procedure. Those aren't critical mistakes, but they may come back to haunt you.

acer

Those `else` clauses are wrong. Just remove both of them. Then put `return Yes` as the new last line of the proc.

Also, try to follow all the earlier advice about `with` and `uses`. And don't use % inside a procedure. Those aren't critical mistakes, but they may come back to haunt you.

acer

What exactly do you mean by "full type"? Please be general, giving a clear, consistent, and useful definition that holds for as many different Maple structures as you can.

You might end up looking toward `disassemble` wrapped around `addressof`, or `ToInert`.

acer

What exactly do you mean by "full type"? Please be general, giving a clear, consistent, and useful definition that holds for as many different Maple structures as you can.

You might end up looking toward `disassemble` wrapped around `addressof`, or `ToInert`.

acer

That's great to know, Will. (Sorry if that was a duplicate question; I might have asked, and been answered, before.)

acer

I guess it might depend on how much you find that you have to program for computations which are not automatically handled (efficiently enough, or at all) in those larger programs.

One big attraction of CUDA, as I understand it, is its general purpose nature as far as numerical scientific programming goes. It's not just using the GPU for graphics calculations. One can do numeric pdes on it, or whatever, provided someone's written the code.

I do not yet know whether Maple's external-calling mechanism can simply call out to a program compiled within CUDA to run on the GPU. It would be great if it did, and good even if it took a little extra effort. It'd be even better if one could cobble together a pseudo-automated process like this to make use of it on "numeric-typed" Maple procedures.

acer