JacquesC

Prof. Jacques Carette

2401 Reputation

17 Badges

20 years, 85 days
McMaster University
Professor or university staff
Hamilton, Ontario, Canada

Social Networks and Content at Maplesoft.com

From a Maple perspective: I first started using it in 1985 (it was Maple 4.0, but I still have a Maple 3.3 manual!). Worked as a Maple tutor in 1987. Joined the company in 1991 as the sole GUI developer and wrote the first Windows version of Maple (for Windows 3.0). Founded the Math group in 1992. Worked remotely from France (still in Math, hosted by the ALGO project) from fall 1993 to summer 1996 where I did my PhD in complex dynamics in Orsay. Soon after I returned to Ontario, I became the Manager of the Math Group, which I grew from 2 people to 12 in 2.5 years. Got "promoted" into project management (for Maple 6, the last of the releases which allowed a lot of backward incompatibilities, aka the last time that design mistakes from the past were allowed to be fixed), and then moved on to an ill-fated web project (it was 1999 after all). After that, worked on coordinating the output from the (many!) research labs Maplesoft then worked with, as well as some Maple design and coding (inert form, the box model for Maplets, some aspects of MathML, context menus, a prototype compiler, and more), as well as some of the initial work on MapleNet. In 2002, an opportunity came up for a faculty position, which I took. After many years of being confronted with Maple weaknesses, I got a number of ideas of how I would go about 'doing better' -- but these ideas required a radical change of architecture, which I could not do within Maplesoft. I have been working on producing a 'better' system ever since.

MaplePrimes Activity


These are replies submitted by JacquesC

Why do you leave U(s) completely general when you have an actual form for it? That would likely make a huge difference. Also, if you know certain things (like x,y,z are real, k[1] is ???, etc), that could make big impact on the feasibility of the computation. 18 equations, 10 unknowns and 4 independent variables, that is a monster of a system! Especially since a lot of your coefficients are "general functions", makes it rather unlikely that a closed-form solution exists. There would have to be a huge number of symmetries for that to happen.
Why do you leave U(s) completely general when you have an actual form for it? That would likely make a huge difference. Also, if you know certain things (like x,y,z are real, k[1] is ???, etc), that could make big impact on the feasibility of the computation. 18 equations, 10 unknowns and 4 independent variables, that is a monster of a system! Especially since a lot of your coefficients are "general functions", makes it rather unlikely that a closed-form solution exists. There would have to be a huge number of symmetries for that to happen.
eval(eval(eval),eval(eval)=eval);
expand(2*eval(expand));
frontend(coeff, [III, a(s,y,z)]); will do what you want. frontend is one of those extremely powerful Maple commands that is seriously under-rated. It's been in Maple for more than 20 years, is used in the core routines a lot, but seldom found in any of the (modern) tutorials, which is a real shame.
Rather like what Wolfram Research has been doing for years?
With completely independent code bases (and thus independent sets of bugs and features). Not what one would consider 1) obvious 2) good software engineering 3) user-friendly
[Since not that many people speak French on here, I took the liberty to translate this post] Hello George, I posted my solver code on my blog, you can read portions of it to help you. I represened the sudoku problem as numbers: it is the lines one after the other, from top to bottom. To solve, use the functions SUDOKU and SUDOKU(000etc231);. I also uploaded some diabolical grids: the "AI sodoku" to tests our procedures (I have not yet found worse than those grids, the "AI etana" is reputed to be the hardest in the world according to the web; my solver solves them all, but takes a crazy amount of time on "madonreika": 42 minutes). I thought to create sequences of possibilities for each case, but my logic does not work, the sudoku procedure fixes possible values for squares and attempts to solve (f3). With this procedure we could generate the set of solutions of a sudoku puzzle (by saving the one found in a sequence when err[i]=0, but I prefer to use break otherwise it would take a lot of time, in particular we could have the set of solutions of a blank sudoku (000etc000), which would give all existing sudokus). Good luck. [Ok, so I also made some stylistic changes to the post]
[Since not that many people speak French on here, I took the liberty to translate this post] Hello George, I posted my solver code on my blog, you can read portions of it to help you. I represened the sudoku problem as numbers: it is the lines one after the other, from top to bottom. To solve, use the functions SUDOKU and SUDOKU(000etc231);. I also uploaded some diabolical grids: the "AI sodoku" to tests our procedures (I have not yet found worse than those grids, the "AI etana" is reputed to be the hardest in the world according to the web; my solver solves them all, but takes a crazy amount of time on "madonreika": 42 minutes). I thought to create sequences of possibilities for each case, but my logic does not work, the sudoku procedure fixes possible values for squares and attempts to solve (f3). With this procedure we could generate the set of solutions of a sudoku puzzle (by saving the one found in a sequence when err[i]=0, but I prefer to use break otherwise it would take a lot of time, in particular we could have the set of solutions of a blank sudoku (000etc000), which would give all existing sudokus). Good luck. [Ok, so I also made some stylistic changes to the post]
There are separate people working on different aspects of the product - documentation being separate from coding. So asking for improvements to documentation does not mean that it will negatively impact ``features''. Why are acer and I (and many others) still using Maple and posting so often on primes if we have so many complaints? For my part, it is because basically I am better off with Maple than without. A lot of people say the same thing about Windows too. And yet they complain a lot. They want improvements. And, at least with Vista versus XP, they will speak with their money: if the improvements are not in the places that matter, many may choose to not upgrade. My complaints all come from the same place: I want Maple to be ever more useful to me. Maple is such a huge product that not all of it can improve for every release. So the hope is that customer feedback will form the basis of where some efforts are put regarding improvements. The message on primes has been fairly clear: it seems that the documentation is currently the weakest spot. Maplesoft will continue to innovate in the areas they see fit (a good thing!); we can (and should) influence where they put time on incremental improvements.
The Dictionary is nice -- but misleading! The definitions are mathematically correct, but they are not always the ones that Maple uses itself. And some of the terminology used in Maple help pages is not defined in the Dictionary, and some terminology that is defined isn't linked. I have found that MathWorld is closer to the definitions that Maple uses, and Wikipedia frequently has more thorough articles (perhaphs except on special functions) than MathWorld. I would like Maple to change the way I do mathematics even more, but keep getting frustrated by the almost-there functionality a little throughout. Just today, I was using Maple 11 (Standard) and cut&pasted from it into a (plain text) email, to show something off. The results were hideous -- way too narrow width (and thus amazingly tall results), awful line-breaking, a weird mixture of small, medium and huge parentheses, as well as have a mixture of hard- and soft- linebreaks. Results from Classic, for the same expression, were much better.
Is there any way to get at the actual data -- I mean posts or Ranking by id? I think this data set would make an interesting one to study via Maple's own facilities, especially the new Statistics package. It would be interesting to do some data fitting (see what distribution the data seems to fit, what parameters, etc). Actually, releasing data snapshots every quarter might be nice, to see the time evolution too.
Dave L moved up a lot -- and from the 2nd to well into the first page. This has had the secondary effect of pushing Nitroxx to the second page, but more interestingly, to now make the minimum ranking of 51 to be on the first page. And a few more posts by Karel Srot will move that up (to 55 anyways). During this week, Will hit 700. And Mariner overtook roman_pearce! acer and dcasimir were once closer together in ranking, but acer's been posting more, so dcasimir has some work to do to catch up. Scott03 is continuing to move up slowly, while DJ Clayworth seems to have stalled.
If you look at the help page for LinearAlgebra:-Zip, you'll see that the last example is component-wise multiplication (also known as Hadamard product, which is what I search for myself when I can't remember how to do this). So zip and LinearAlgebra:-Zip can do this. Another way is via ArrayTools:-ElementMultiply. Of course, both of these commands just call zip(`*`,...) !
If you look at the help page for LinearAlgebra:-Zip, you'll see that the last example is component-wise multiplication (also known as Hadamard product, which is what I search for myself when I can't remember how to do this). So zip and LinearAlgebra:-Zip can do this. Another way is via ArrayTools:-ElementMultiply. Of course, both of these commands just call zip(`*`,...) !
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