1,541 reputation
518
bio website linkedin.com/pub/eric-brown/…
location Skokie, Illinois
age
visits member for 1 year, 10 months
seen 10 hours ago

Jul
22
comment Converting datasets to nested lists
There are very nice and clever. Would it be possible to modify your answer so that the "SNO" (e.g. "S1") is not in the {"S1","P1",300} part?
Jul
19
comment What are the Slot Names in a Dataset?
@Karsten7. Thanks, that does it. If you had put this as an answer, then I would be happy to close the question.
Jul
13
comment Dataset with no members
@TaliesinBeynon Thanks for your reply. I gathered that you are the author of this code. I'm really happy about this functionality, especially the ability to have data sets inside of data sets (relations inside of relations).
Jul
12
comment Why does FindFit seem to have trouble fitting exponential data?
@RahulNarain I believe that FindFit minimizes, e.g. the least squares error, whereas NonlinearModelFit maximizes the value of the parameter values with respect to a likelihood function.
Nov
22
comment Is Mathematica an Implementation of the Wolfram Language?
@halirutan now i get it. :-)
Aug
30
comment How to send a function definition to MathLink from C/C++?
@Szabolcs I haven't been able to figure out how to round trip from C (I will keep trying.) Agreed, it will be a big performance hit over C or Fortran RNG, but if the RNG for exotic (or novel) distributions is not available, then Mathematica should be acceptable for an ad hoc RNG for development purposes. (Of course you know this, just letting you know that I know :-)
Aug
26
comment How to send a function definition to MathLink from C/C++?
@Szabolcs one reason to call Mathematica from C is if the C code already exists (and is kind of complicated to build/refactor). I have a case now where I wish I could shoe horn in Mathematica's random number generators into the C program, and I would be off to the races.
Aug
26
comment Write C/C++ programs calling Mathematica functions
If you could point me to the specific page that demonstrates the "round trip" in C that you have shown in Java, then I would be happy to eat crow. What I see on the Mathlink documentation is very high-level.
Aug
26
comment Write C/C++ programs calling Mathematica functions
I regret that I have to downvote this. The question asks about C/C++, but the solution is in Java! The link provided goes to the top level of MathLink, but the whole point of the question is that MathLink docs generally cover Mathematica -> C rather than the other way around. (I have a similar problem now, which brought me to this question.)
Jul
17
comment How to save a web page in mathematica?
@Stefan For example, I could Import[ coolMMAStackExchangeURL, "WebArchive"] into a section, and then I could do some of my own calculations in a new section below. (It would be just like a Wolfram Alpha query). I could save the whole file in one convenient notebook. Could I just embed a hyperlink to the web page? Yes. But one could not guarantee the web page would always be there. (I like webarchives on Macintosh.) Also, the content would be available to me offline. How often am I offline? Seldom, but wireless is often spotty. Anyway, many people even want emacs to have an html renderer...
Jul
17
comment How to save a web page in mathematica?
I think it would be super-sweet if I could Import[ webpage ] and it would render the whole web page in an output cell of Mathematica.
Jul
12
comment How to fit 3 data sets to a model of 4 differential equations?
Also, is pfun even a function? Should it be pfun[{k1_,k2_…,k10_}]:= *definition* or something? I'm afraid I have to agree with the other comments that your task is almost impossible with the paucity of data and the number of parameters. (This would probably never survive a sensitivity analysis) But, I am interested in the general problem of fitting differential equation parameters to data sets...
Jul
7
comment Hardware Performance Metrics for Mathematica
@OleksandrR. That does nicely! My Macbook Air i7 gets 0.898. Maybe this will give some perspective of the general performance of portables.
Jul
7
comment Hardware Performance Metrics for Mathematica
Needs["Benchmarking`"]; Benchmark[] Now if I can find a webpage that has a list of results for different machines...
Jul
3
comment Importing specific columns of a .txt file
(I am not sure why this is getting dinged.) I don't know how to do this either with ReadList. Anyway, it may be just as easy to read the whole data set with ReadList, then take the columns with dataReadIn[[All,{1,4}]] Otherwise it could be a job for OpenRead, Read, Skip, etc.
Jul
2
comment Doubts on scripting: error messages when trying to run and how to process lots of files
@rm-rf He only has hundreds, so I guess he should do it in the front end ;-)
Jul
2
comment Doubts on scripting: error messages when trying to run and how to process lots of files
Yves and rm: He clearly states that he wants it scriptable. The front end may not be appropriate for his tasks.
Jul
1
comment triple NIntegrate fails
Another suggestion: if you need the 10^-48 stuff for scaling, then you may want to move that inside of the NIntegrate so that it does not blow up or even vanish.
Jul
1
comment triple NIntegrate fails
Another issue: 1) I would combine all the NIntegrates into one 2) Is it possible for the argument to the Sqrt to become negative? Plot3D[r12^2 + r13^2 - 2 r12 r13 n /. n -> 10, {r13, 0, 150}, {r12, 0, 150}]
Jul
1
comment triple NIntegrate fails
Some suggestions: 1) please don't use capital C because it is already used in Mathematica. Maybe try small c. 2) T is not defined in your equation, neither as a parameter nor as a variable for integration.