@EdenHarder Isn't it possible to create (for this specific example) the first two elements first which fulfill your condition and then append the rest of the permutation?
@EdenHarder Try searching the site for Permutations and memory. And perhaps memory and list generation in general. Problems with memory in this context should be fairly common. One quick search led me to a way of doing it procedurally with the Combinatorica package that might help: reference.wolfram.com/mathematica/Combinatorica/ref/…
@halirutan Thanks! But the order may be complict, for example, #[[1]] < #[[2]] < #[[3]] and #[[4]] < #[[5]] < #[[6]] and #[[7]] < #[[8]] < #[[9]] .
@Calle Thanks! It is helpful! But I do not find a proper function. Given the order , for example, #[[1]] < #[[2]] < #[[3]] and #[[4]] < #[[5]] < #[[6]] and #[[7]] < #[[8]] < #[[9]], there are only 1680 permutations but not 9!. So, we need a more efficient code.
@Mr.Wizard Do we have a canonical answer for injecting code into held expression? I'm really sure I read something from Leonid about this. It would probably good to give this link in this Q&A and/or close it as dup.
I wish to make functional replacement inside Held expression like this:
f[x_Real] := x^2;
Hold[{2., 3.}] /. n_Real :> f[n]
=> Hold[{4., 9.}]
But I get Hold[{f[2.], f[3.]}] instead. What is the best way to make such replacement without evaluation of the Held expression?
@Mr.Wizard Hehe, don't try. I had just posted a comment on the question about the held derivative, and when I came back here I saw that my comment was about to get superseded
@Mr.Wizard Hey, about that question of substrings. You interpreted that a nice solution would allow you to style substrings that may be overlapping, such as "make all substrings matching "asdf" bold", and now "make all substrings matching "dfgh" red", so as to get some bold and red, some just red and some just bold, right?
@Mr.Wizard No, but I thought it might be interesting to try :)
@Mr.Wizard There's also this other question, old question I hadn't seen. mathematica.stackexchange.com/q/16067/109. I don't know if that's what he's asking but it made me think of a version of "simplify" that returns something that reduces to the original expression
@Rojo It's obviously practical because word processors work this way, but I remember trying it and getting frustrated. I suppose on reflection one would have to insert markers (markup language) and then generate styling afterward.
Meaning, that it could also define new variables to minimize its complexity function, finding common subexpressions. Have you seen anything like that around?
@Rojo There's a group of questions that relate to what I think you're describing. IIRC if you search for OptimizeExpression you'll find some of them; also searching for Daniel Lichtblau's posts containing PolynomialReduce or GroebnerBasis should be fruitful.
It's a common question with many flavors; it would be great to have a canonical post but I'm not sure that is even possible.
How does one find stats on this group, to see if more users are coming to Mathematica forum over the time period it was started? it will interesting if someone can post some such stats...
are there on some stackexchange site somewhere? like how many questions are asked per month, how many are answered, etc... will be fun to see
@Nasser There are statistics for the moderators to view. We are not supposed to disclose all of them to the public and at the moment I can't remember which ones we are allowed to share. I'm sure @rm-rf will remember. I do know I can summarize the results for you; give me a minute to look.
@Nasser Which of these interests you?: New Users, Total Page Views, Number of Visits, Number of New Visits.
Heh, thanks, but I just handle the pattern matching, list manipulation, and programming stuff. The site would be quite poor if there were only clones of me answering questions.
@Mr.Wizard I was just wondering how popular the site is becoming really, that is all. not sure what is the correct measure for this now. may be rate of new users will do?
By popular demand, here is a place for people to post regularly-updated metrics of traffic and other indicators of how Mathematica.SE is developing.
Please post sets of analysis from different sources as (community wiki) separate answers.
@Mr.Wizard I think I do not understand it fully yet so let me ask you a question. Ordering needs information about whole sequence of elements from two lists. This seems to be unnecessary. why not just part1 - part2?
but I might miss something so don't judge me too harshly :P
the notebook is there. Please download and just run the GUI there inside it. I am just looking for some feedback if it is OK, clear to use, etc... so I can make any changes if needed before I submit it to WRI
the file is there, v4.nb
if nothing is clear to use, or find any issues, please let me know, on your time. not urgent.
@SimonWoods yes. I make heavy use of Grid, which helps alot.
The hardest part is this: Make sure nothing shifts while running. I hate to see any image or plot shake or any numbers moves from a fixed location. This takes the most time to do. I see so many demos on WRI where this is not taken care of. But this is the hardest part to do.
@SimonWoods yes. Making the plot fit the whole space around it. Changing aspect ratio can affect the title shaking, etc... I really do not have a fixed formula. it is lots of trial and errors until it comes out right.
I think WRI should make CDF formating open, like PDF. THen it will take over. There is really like it out there. it is amazing technology, but not used much
Adobe made PDF format open, yet everyone still use adobe reader. So if WRI does the same with CDF, still everyone will use WRI reader. NO difference, except everyone will start using CDF and publishing CDF's
it will take 1000 lines of OpenGL code to do the same using few lines of mathematica 3D commands and options...and CDF's can run on the web as well.
@Nasser That's not true, on OS X everyone uses Preview, for example. Often one uses the web browser. And as I understand it, the CDF is basically MMA so they can't make it "open" without revealing their technology for MMA to competitors.
@Calle the point is that it will become open standard, and then there is more chance of people using it. it does not matter if the reader is free. There are many who will not touch closed technology. WRI will not be able to have CDF's used much more if the format of the CDF is closed.
any way. Just my opinion, that is all. WRI can do anything they want ;)
@Nasser But the player is a full Mathematica Kernel and everyone who wants to run a CDF still needs a Kernel to have all functionality. How do you want to make this open?
Alright, maybe I'm just narrow-minded at the moment. To me, CDFs is a way of sharing MMA code. I don't see non-MMA people using CDF. Any other program created to make CDFs will only be able to implement a subset of MMA anyway.
@Nasser Let's say we are talking about the Adobe Illustrator format and assume it would be a simple XML file and all specs are given. Who would help this?
You still need the illustrator.
And unlike PDF, where it is just about displaying something CDF really needs all the fancy algorithms. So a alternative viewer would have to reimplement Mathematica
@halirutan I know. So WRI player is still needed. Just like I need adobe PDF reader to read a pdf file. THe difference is that anyone can publish a PDF file. THis is the point.
@Nasser But that's my point; anyone can not implement a read because that would amount to reimplementing the MMA kernel. And without the MMA kernel one cannot try one's CDF code, so it's practically impossible to build a CDF without MMA.
@Nasser The thing is twofold: First, it is very unlikely anyone would create more then the most simple CDF without Mathematica, so it would not have the same use as a PDF where you can create all fancy stuff with many programs like InkScape, LaTeX, ... So making it open would not really make a difference on how many people use it.
@halirutan again. Let then call it a marketing point. Making CDF format open and standard, even though no one is able to implement a reader for it, will at least remove the main objection against using it now. That it is closed format. At least WRI can market is as open format and standard bla bla
The second thing is: By making it an open format, I'm pretty sure Wolfram has to think again about it's security issues. I would say if the format is open, one can easily hack around the restrictions which are currently implemented.
@halirutan I doubt hackers will make any closed format stop them. Look at windows, it is hacked all the time. but windows is closed source... any way, I think I said all what I can on this, just an opinion again ;)
I wonder what is the logic behind accepting an answer but not upvoting it? It's kind of like saying "your answer is no good, though it did solve my problem"
Yet more secret functionality from the people who brought you Graphics`Mesh (but didn't tell you about it)
There's a set of axis/frame options which you can get with
axisthemes = "Axis" /. Charting`$PlotThemes
There are more themes in Charting`$PlotThemes but it seems to be an incomplete list. I've used some code to extract theme options from the downvalues of Charting`ResolvePlotTheme