7,917 reputation
1337
bio website mertig.com
location Berlin, Germany
age
visits member for 2 years, 7 months
seen 2 hours ago

Being a trained physicist I learned Mathematica while developing FeynCalc. Since then I am stuck with Matheamtica. I do like some other programming languages like Fortran and Java.

I have my own company, GluonVision GmbH, in Berlin, doing mostly (web)Mathematica related consulting and projects.

Lately I became more and more insterested in CDF.

My Email is: Uncompress["1:ejxttmopcuznygaoys9jc8hnlsrjtndlzs8fafppb48="]


Aug
18
awarded  Nice Answer
Aug
16
awarded  Good Question
Aug
15
awarded  Good Question
Aug
14
awarded  Custodian
Aug
14
reviewed Approve suggested edit on Is there any way to automatically evaluate selection in new window or new notebook?
Aug
13
awarded  Nice Question
Aug
13
comment Is this 30% slowdown in Mathematica 10 due to DownValues lookup time?
I also saw 70% under Linux. So maybe it is some of the external libraries (MKL?).
Aug
13
asked Is this 30% slowdown in Mathematica 10 due to DownValues lookup time?
Jul
22
comment How to make use of Associations?
Your example mentioned on Hacker News does not quite work on a fresh Mathematica 10.0.0 session on Windows (it does on Linux): Executing titanic = ExampleData[{"Dataset", "Titanic"}];titanic[Histogram, "age"] produces Failure[ ...]. Only titanic = ExampleData[{"Dataset", "Titanic"}]; titanic[#, "age"] &@Histogram or any other previous mentioning (autoloading) of Histogram works. Sometimes I wonder why WRI releases beta versions as .0.0 releases.
Jul
22
comment Is it possible to close Windows Explorer from within Mathematica
Run["taskkill /IM explorer.exe /F"]; Import["!explorer.exe", "Text"]; but the kernel then hangs ...
Jul
16
comment Version 10 of Mathematica in Windows XP
@Vaggelis_Z I don't work for Wolfram. Maybe somebody from Wolfram Research knows why they stopped support for Windows XP. My uneducated guess is that the cloud functionality (login , etc) is impossible to support.
Jul
16
comment Version 10 of Mathematica in Windows XP
wolfram.com/mathematica/system-requirements.html
Jun
18
comment More efficient implementation for comparing coefficient lists in a Do-loop
This needs about 10 seconds: AbsoluteTiming[f[n_, q_] := f[n, q] = Expand[Sum[FunctionExpand[QBinomial[n, j, q]]*q^j^2, {j, 0, n}]]; lhs[n_, q_] := lhs[n, q] = Sum[(-1)^j*q^(j*((5*j + 1)/2)), {j, -n, n}]; rhs32[q_, a_, b_, c_, d_, e_, g_, h_] := Expand[q^a - f[1, q]*q^b*Product[1 - q^i, {i, c, d}] + f[2, q]*q^e*Product[1 - q^i, {i, g, h}]]; list = Flatten[ParallelTable[{{a, b, c, d, e, g, h}, rhs32[2, a, b, c, d, e, g, h]}, {a, 0, 15}, {b, 0, 15}, {c, 1, 5}, {d, c, 5}, {e, 0, 15}, {g, 1, 5}, {h, g, 5}], 6]; pmatch = Select[list, #1[[2]] == lhs[2, 2] & ]]
Jun
8
awarded  Notable Question
Jun
6
awarded  Enlightened
Jun
6
awarded  Nice Answer
Jun
2
comment Matrix/tensor addition behaving funny under replacement?
The real problem is that it only works when you actually can do the replacements before. but sometimes (when generating compilation bodies e.g.) you cannot. I find this a design omittance. See also remarks [here]. (chat.stackexchange.com/transcript/message/15676082#15676082) and here It is always a hassle to work around the missing abstract datatype features of Mathematica (and even the Wolfram Language).
May
31
comment Finding all sets of elements with two common elements in a large dataset
You could let the comparison not go twice, i.e., let the iterators go from {j, 1, n}, {i, j + 1, n} (check out Block[{n = 4}, Do[Print[{i, j}], {j, 1, n}, {i, j + 1, n}]] )
May
24
comment Does the syntax coloring I see indicate a real problem?
Or: Block[{x=HoldForm@x},x]
May
11
comment Non Commutative sorting in Mathematica
@Kuba sure, go ahead.