OCaml or F#, depending on your tastes. Both are supersets of MMA, but don't come with a definition of MMA. You'd have to provide that yourself. Jon Harrop once did.
@acl and the poster claimed that Jon Harrop had implemented Mathematica in F#, which is untrue.
On another topic, we are getting quite a few click-throughs from CrossValidated, Physics.SE, and Math.SE. Possibly an initial surge, as once people have seen it once, they won't click a second time, but still a good sign.
@Verbeia I am somewhat worried that the level of questions has been dropping recently (not in terms of level of expertise of the asker, but rather in terms of how thought-through the questions are)
on the other hand, with greater exposure, this is unavoidable. and the process of community vetting seems to be working.
@acl exactly - i think if we stay friendly and constructive, and improve what is salvagable, we end up building contributing members out of newbies. Some of our editors/closers were not on SO, or were low-rep occasional participants there.
Guys, do you know some function that can count how many of each element is inside a list? Like: I have this list: {1,1,1,2,2}, then this function will return me {3,2} or {3(1),2(2)}.
I just retagged all questions with performance to performance-tuning. There's one remaining question, and I'm not sure how to tag it, as it's not about performance tuning in the same sense as the others.
I have found that despite Mathematica's numerous updates, each of which have added much functionality, one fundamental issue remains unaddressed: The unresponsiveness of the UI when I make a mistake (specifically, this is in Mac OS X, but the problem may exist in the other OSes). The problem has ...
This is a Python program supposed to run on a machine without Mathematica so to emulate Mathematica's kernel by calling the Wolfram website. So I want to know the restrictions imposed by such method. I also want to know how I can improve this program so that to extend its abilities and minimize ...
When I see a question asking "is there a built-in function to do this-and-this", and it is in need of fixing up its tags, I am adding functions when there's no clear more specific tag to add. If you have another suggestion, let me know.
When the solution turns out to require implementing something non-trivial, I'm adding programming instead.
BTW all this retagging is bumping up questions in the active list. Feel free to correct if you see anything that doesn't seem right.
There's an migrated question incorrectly tagged with mathservice. Can any of the mods remove the tag? I can't access the tag because the question is migrated (and has different tags on the target site). @Sjoerd @J.M. @MrWizard
Let's use this thread to post our favourite third-party packages.
Instructions
Please post only those packages that you actually use yourself (not
any package you found) or packages that you created yourself.
Each answer should be one package, and should preferably contain a
sh...
Actually I don't use that many third-party packages regularly enough to post more than that one answer, but some good candidates for posting are, I think: NCAlgebra, xAct, mEngine. I used the last one for a while. Then there's Pythonika, but after looking at its source code I lost all trust in it, so I don't want to post it.
We've talked about here and there pieces of this, but what should go in our FAQ? What do you think needs to mentioned in our FAQ? Obviously, what is considered on-topic/off-topic, and quite possibly a number of items from this list. But, we should start making progress on this question.
(This is...
@Szabolcs There's the definition where solutions would involve LinearProgramming[] and/or NMinimize[], but mathematical-optimization is supposed to cover that already...
@JM I see you already renamed it. But the questions that were tagged were not about optimization, so I think it should still be removed from those questions ...
@RebeccaChernoff It was suggested I ask you about creating community blogs. Our site (Mathematica.SE) will soon be ready to have a blog. We have topics and volunteers. What is the procedure for requesting a blog? What else do we need to do before getting one? We don't have a fixed schedule, but I believe the current level of interest can sustain a low volume blog in the long term.
@JM Are you interested in contributing a few posts?
About the schedule: if we keep it low volume, and don't publish new posts too often during the initial excitement, it should sustain itself in the long term.
I was thinking more monthly than weekly, and of course it wouldn't be the same person every time.
Right now there are 4 (5?) people who said they're interested in writing a few posts. That should keep it going for half a year with a monthly frequency.
@JM I did ask for entry suggestions here. I thought we can start a thread with concrete suggestions (i.e. who wants to write one RIGHT NOW) when we have a blog set up.
@JM I think it doesn't always have to be something very generally applicable (e.g. programming techniques such as closures) or something very spectacular (like some of the visualizations here: confetti & word cloud). Your post on implementing a new random number generator and plugging it into Mma's RNG framework would have been a nice post.
Also, I think we can keep a faster schedule than 1 post / month, but I don't want to aim too high and let it become a burden.
It should be something fun, and posts should be written because people want to, not because we need to keep a schedule.
@Heike I wrote the owner of that web page 6 years ago, asking for the data file, and offering to write a much better version of the Mathematica code, but he didn't respond.
Needs[LinearAlgebra`MatrixManipulation`];TakeRows[TakeColumns[matrix, {1, 6}], {3, genes + 2}] seems to be equivalent to matrix[[2;;genes+2, ;;6]]. I'm pretty sure Matlab has a similar construct, so why make things so complicated in Mathematica?
He does seem to have heard of the concept Table, but then he does things like this: positions = Table[0, {a, 1, arrays + 1}] Do[ positions[[a]] = Flatten[ Position[Flatten[counter], a - 1]], {a, 1, arrays + 1}]
@RM CurvesGraphics6 can be loaded by clicking a button in the source notebook. I did not actually install it and used Get/Needs, so I didn't include that in the answer either.
@Szabolcs ok, I'll post it in a few days after playing around and getting familiar with it... right now it fits the "please do not post any package you found" rule :)
@Heike but it was written by someone who certainly knows of more options to various functions than I do, and I use mathematica for most of my working time...
@acl I don't think the author of that blog had much to do with the Mathematica code. It seems to be almost literally taken from the notebook on this site.
Does anybody have a good reference on the concept of "functions as vectors"? I've searched the web, but the only decent explanation I've found is this one. I'd like to get more information on the concept, but most of what I find is about "vector functions", which doesn't seem (to me) to be the same thing.
I've also checked math.SE, but the answers were uninspiring - to me at least.
@CHM Have you studied a bit of abstract algebra? In abstract algebra we deal only with certain properties of operations, such as associativity, commutativity, etc., and don't care about what those operations are, or what they're operating on. E.g. addition and multiplication can be equivalent from this point of view: they're associative, commutative, there's a null element and elements have inverses.
@CHM If you get used to this, then you won't be bothered any more that now we're adding and and "rescaling" complex functions instead of number-tuples
@Szabolcs I've had a linear-algebra course where we had to prove if this or that is a vector space, using the 8 (I think) criteria - but nothing more than that.
The mathematics taught to a chemistry major (in my univeristy, at least) are deficient, to say the least.
One course plows through everything from linear algebra, differentiation, integration, ODEs, PDEs, statistical analysis, Fourier analysis, etc. in 15 weeks, three hours per week.
The funny thing about the last calculus course I took... there was way too much emphasis on integrals (single and multiple), and not much on series, when it turned out that the physical chemistry course I subsequently took was heavier on the series than on the integrals...
@Szabolcs "It helps to change the way you think of vectors rather than changing the way you think of functions." - Pretty much like what you said to me.
@JM Haven't had the time. I'm actually running around trying to get my head around what is important and what is not. I guess that's every neophyte's fate.
ok I am asking the question unclearly. in any case, I really enjoyed Sakurai's "modern quantum mechanics", but I doubt you'll like that (it is probably different to how you were taught it). Cohen-Tannoudji has lots of details; I don't think I liked it but maybe it depends on the person. chapter 5 of bransden and joachain describes things in detail, but I don't think they explicitly point out the general concepts of vector spaces. landau-lifshitz never breathe a word about vectors spaces...
but all this depends on why you need to know this. there's no point in learning abstract formalism if you don't need it
@CHM If memory serves, the models for polyacetylene and polyphenylene are rather simple, but that's due to the assumption of infinite extent. It might still be a good lead, though.
@CHM Unfortunately, it's been quite a while since I looked into this, and my connection to SciFinder is currently crapping out. :(
Unfortunately, that's all my time for today. See y'all later.
@CHM ah that was great! I don't remember if it has anything specifically on this though
well, ch 4 in Byron and Fuller is the one I liked. But this may be overkill at this stage (I just look through cohen-tannoudji and their discussion seems fairly detailed and explicit)
@Heike I think it is a very shocking thing, not only as a theory, but also as a thinking process. The guys who developed QM in the early days of the 20th century were working against their intuition
@belisarius Wasn't Einstein very much opposed to certain conclusions in QM
Sometimes it's nice when karma works in my favour. I was just wandering what plants to get for a shady bit in my garden that I had cleared of ivy when my neighbour pops over the fence asking me if I would like a spare hosta.
I tried to fit some data with boundary conditions, but FindFit just could not work. Does anyone know the reason?
Details:
The function to be fitted is A*Tanh[x+a]+B. Data is provided from x=0 to some positive number.
I set the requirement that the fitted function should be same as Tanh[x] at...
OCaml or F#, depending on your tastes. Both are supersets of MMA, but don't come with a definition of MMA. You'd have to provide that yourself. Jon Harrop once did.
Let's use this thread to post our favourite third-party packages.
Instructions
Please post only those packages that you actually use yourself (not
any package you found) or packages that you created yourself.
Each answer should be one package, and should preferably contain a
sh...
In Mathematica, using Edge Detection and Hough Transform:
I tried to fit some data with boundary conditions, but FindFit just could not work. Does anyone know the reason?
Details:
The function to be fitted is A*Tanh[x+a]+B. Data is provided from x=0 to some positive number.
I set the requirement that the fitted function should be same as Tanh[x] at...
