Per Alexandersson

less info
753 reputation
313
bio website www2.math.su.se/~per
location Zurich, Switzerland
age 27
visits member for 2 years, 6 months
seen 11 hours ago

Currently interested in Schur functions and semistandard Young tableaux and misc. related representation theory and combinatorics.

Phd thesis defended 2013, titled Combinatorial Methods in Complex Analysis.

I keep an eye out for interesting results related to complex dynamics, computability, and computer-assisted research. I use Mathematica extensively in my research. My other main programming languages are Java, LaTeX, PHP, C, etc.


Aug
8
comment How can I use the Klingon alphabet symbols?
@Mr.Wizard: Well, I play around a lot with Schur polynomials, which are characters of GLn, and also irreducible characters of Sn. In general, I would like access to structure constants, such as Littlewood-Richardson coefficients, Kostka coefficients and Kronecker coefficients. My question about generating Gelfand-Tsetlin patterns on this site can be used to compute Kostka numbers, for example. LR-coefficients can be computed by counting lattice points in polytopes, another thing I really think Mathematica could be better at.
Aug
8
comment How can I use the Klingon alphabet symbols?
Ok, so you are telling me, that the MATHEMATICAL software supports Klingon characters, but not irreducible characters...
Aug
7
comment $SU(4)$ Structure constants in mathematica
Mathematica is perhaps not the best software for the task; i think there are better suited programs out there tat has these built-in.
Jul
2
awarded  Curious
Jun
16
comment Smooth Peter de Jong attractor
@Kuba: The implementation I have is written in Java, and is open-sourced here: sourceforge.net/projects/flamethyst Some images created can be found here: people.su.se/~peal0658/index.php?page=fractals
Jun
16
comment Smooth Peter de Jong attractor
Google "Flame fractals". I create this type of fractals a lot; 10⁵ is not nearly enough iterations. You would like about 2000 iterations PER PIXEL in the final image to get a decent result.
Jun
14
comment Extract memoized results in the form of a rule
Ah, yes, of course! I feel silly now.
Jun
14
asked Extract memoized results in the form of a rule
Jun
10
comment State “i” goes to state “j”
I would guess it means states accessible from either 1 or 4.
May
8
comment Mathematica sporadically crashes on open
Because, that makes sense... sometimes, one wonders...
May
8
answered Drop last element of parts of a list
Mar
30
answered Do multiple instances of Mathematica run completely independently?
Mar
28
awarded  Nice Answer
Mar
28
comment Creating sculptural forms using graphics primitives
Thanks! Absolutely not, I was just a bit lazy to add it myself :)
Mar
28
answered Creating sculptural forms using graphics primitives
Mar
16
comment Finding lags of time series with `Do`
Oh, L[t_]:=t-k; should most definitely work. But dont use capital letters as variable names, these might already be used by Mathematica, in any case, it is bad practice.
Mar
16
comment Finding lags of time series with `Do`
Oh, you want ListPlot[L/@Range[5,100]]
Mar
16
comment Finding lags of time series with `Do`
Hm, ok, well, I am not entirely sure what info you got, and what is unknown...
Mar
16
answered Finding lags of time series with `Do`
Mar
5
suggested suggested edit on Generating Gelfand-Tsetlin patterns