1,380 reputation
514
bio website quantum.at
location Vienna, Austria
age
visits member for 2 years, 7 months
seen 15 hours ago

PhD student in Theoretical Physics

Research interests include Quantum Optomechanics and Quantum Optics


Aug
8
comment Strange behaviour of UpSet
@TeakeNutma Lol, sorry for that :)
Aug
8
comment Strange behaviour of UpSet
I don't see this under V8 btw.
Aug
8
comment Strange behaviour of UpSet
Indeed, I can reproduce this under V10 on Linux
Aug
6
comment How can I get the number of slots in Function?
That makes sense. Don't know why I didn't think of that. Sorry. I only realized that *## doesn't work (and -## neither for that matter). Thanks for the link, I wasn't aware of that post. I looked for "monad" but came up empty handed.
Aug
6
comment How can I get the number of slots in Function?
Mr.Wizard, can you explain how the evaluation of (3) works? Why is + special in this respect and are there other operators which work in the same way?
Aug
6
revised What's the difference between Inactive and HoldForm?
added 429 characters in body
Aug
5
comment Making time-index dependent state-space models - where has the Kalman filter gone?
I see... It seems you're right and Mathematica doesn't support time-dependent Kalman filtering out of the box right now. On the other hand (and I'm guessing you know that), it is fairly easy to implement this functionality yourself (at least for simple models).
Aug
4
comment Mean squared error of two matrices
I think your approach makes total sense if the matrix elements are uncorrelated. If they are not, there might be a better way. You could try searching CrossValitated and come back here once you found a suitable method.
Aug
4
comment the winding number for the circle map (Arnold tongue)
Maybe, but I don't want to expand the nested expression for n=500. Only machines with a lot of memory will be able to handle it.
Aug
4
revised the winding number for the circle map (Arnold tongue)
updated performance comparison
Aug
4
comment the winding number for the circle map (Arnold tongue)
Ok, put my timings there. (The original timings were different for me, so I exchanged all of them. Hope that's ok.)
Aug
4
suggested suggested edit on the winding number for the circle map (Arnold tongue)
Aug
4
comment the winding number for the circle map (Arnold tongue)
That's not a fair comparison though, as ff[1/100,1/500] will compute the exact solution. Try ff@@SetPrecision[{1/100, 1/500}, 880];//AbsoluteTiming! For me the timing differences are negligible.
Aug
4
comment Making time-index dependent state-space models - where has the Kalman filter gone?
What exactly is the question? You are looking for KalmanEstimator I think. And StateSpaceModel is not new btw, it's been there since V8.
Aug
3
comment Why does Mathematica appear to change the head of certain expressions?
Mr.Wizard, do you have new insight in the problem with the short forms you linked to? You said in one of the comments you might post a partial solution at some point. I'm sure many people would be interested (including me)!
Aug
1
comment Dataset: cannot reproduce a basic example. A bug?
Works for me under Linux (both, directly evaluating the example in the docs and pasting this snippet)
Aug
1
comment Mean squared error of two matrices
Also, see the Matrix Norm article on Wikipedia. It might make more sense to do something like Norm[mat1-mat2] depending on the problem. In quantum physics for example the distance between two density matrices is often measured by the trace distance.
Jul
31
comment How to group each element with each consecutive elements in one head
@Uh, I like the use of the new Composition operator! Also, I would have gone with MapIndexed too but maybe combined it with Outer(but I don't have Mathematica to test right now)
Jul
30
comment Minimum and maximum values under conditions
Damn you... ;-)
Jul
30
comment Minimum and maximum values under conditions
I think my new version is even faster though!