1,420 reputation
517
bio website quantum.at
location Vienna, Austria
age
visits member for 2 years, 11 months
seen 2 days ago

PhD student in Theoretical Physics

Research interests include Quantum Optomechanics and Quantum Optics


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!
Jul
30
revised Minimum and maximum values under conditions
added 111 characters in body
Jul
30
comment Minimum and maximum values under conditions
Well that was just a matter of time, wasn't it... :)
Jul
29
answered Minimum and maximum values under conditions
Jul
28
comment Using ReplaceAll to replace a head
I find the last statement that "Replace [...] acts from the inside out" rather missleading. What about Replace[a[b[c, d]], head_[arg__] :> newHead[arg]]?
Jul
27
comment Best practice of passing a large number of parameters to functions
@Mr.Wizard I was referring to the latter case. Thx for the explanation!
Jul
27
comment Best practice of passing a large number of parameters to functions
@Mr.Wizard Can you explain to me why p:_Association:par does not work in this case? Is it because par does not match _Association in its unevaluated form?
Jul
26
comment How can I mend this broken heart?
@YvesKlett To be fair, it's one of the best titles on this site! Made me smile :)
Jul
25
awarded  Nice Question
Jul
23
revised Is there a list of Octave functions mapped to the related Mathematica one?
Corrected ones,zeros
Jul
23
comment Is there a list of Octave functions mapped to the related Mathematica one?
@Mr.Wizard Will do, I just wasn't sure what you'd want to do with solution 3 :) Anyway, I agree that it is probably really hard to maintain this list in a sensible way. MATLAB is heavily overloaded and Mathematica is too.
Jul
23
comment Is there a list of Octave functions mapped to the related Mathematica one?
@Mr.Wizard I just realized that your first example is not correct (so is the zeros one): ones(n) creates a n-by-n matrix of 1s! The equivalent to your commands is ones(1,n) or ones(n,1) depending on the interpretation.
Jul
23
comment Automatically growing lists as in MATLAB?
Sorry if the following is obvious to you (also, it's a bit off-topic): This is bad practice in MATLAB and in a direct translation also in Mathematica, as in this way new memory needs to be allocated every time you add an element and this takes a lot of time. Better preallocate by x=zeros(1,n). (Of course this doesn't matter much if you do it only once in the whole program.)
Jul
22
comment Is there a list of Octave functions mapped to the related Mathematica one?
@Mr.Wizard Oh, I just found this on Wikipedia: "In fact, Octave treats incompatibility with MATLAB as a bug [...]". I think we are safe :)