One of the items missing in the "combinat" package is that there exists no procedure to produce one combination at a time from C(n,k). The only possibility is to generate a list of all possible subsets of C(n,k) in a single go.

I am looking for a function/library to generate sequences of combination C(n,k), which would generate the next (successor) sequence, given a sequence. ie next:=some_proc(n,k,prev) should return the next sequence after the sequence "prev". Is this available anywhere ?

Consider the task of extracting the constant-term from a multivariate polynomial. This seems a common operation; I expected that there would be a predefined command for doing it. Alas, I could not find one. The usual suspects, coeff and tcoeff, do not directly do the job: coeff does not work with multivariate polynomials and tcoeff returns the coefficent of the lowest-order term, which may not be the zero-order term. Here are two simple procedures that implement different ways of solving this problem:

I have problems with assume integer. Here is a worksheet yielding a wrong solution. Is there something other than assume(integer)? > restart: > assume(k,integer); > is(k,integer); > is(l,integer); > t1:=int(sin(x)*sin(k*x),x=0..Pi); > t2:=int(sin(x)*sin(l*x),x=0..Pi); > limit(t2,l=1);

I want to create a list and apply sin(x) to it. Is there something that can help me do the following.... Apply sin(x) to a list as in... sin[2, Pi, Pi/3] Please let me know.

In a new PC with a nVidia graphics card under Win XP Pro I have found that
plots, using the Classic interface (Maple 8 included), show a cyan background
by default, instead of white. Default means PlotBGColor=default or 255 255 255
in maple10.ini.

Clicking with the mouse on the plot turns the background white, both for
inline and window output, but e.g. using the window output, and pressing the right
arrow turns the background cyan again.

On the other hand, plot background in Standard interface shows white.

I have not realized of any other application showing this problem.
Any idea on its origin?

Here is a simple Maplet example,

New here and not sure if this is where the bugs go. Assuming it is... Using Maple10, build 190196 and Linux; entering the following >map(Im,Matrix(1,1,shape=identity)): gives back 1x1 identity matrix (that is, [1]). Fixed by >map(Im,1.*Matrix(1,1,shape=identity)): which returns [0.], as it should. Cheers

I am trying to solve the following system in (L,N) with Maple eq1 := 449.7102399/(L-115.6885356*N^.98*L^1.019)^.1* (1-117.8866178*N^.98*L^.19e-1)+15-5894.330889*N^.98* L^.19e-1-411.72/(48-L)^.6e-1-985.8471121* exp(-3.638-.174*N)/L^.326 = 0 eq2 := -50985.79270/(L-115.6885356*N^.98*L^1.019)^.1/N^.2e-1* L^1.019-5668.738244/N^.2e-1*L^1.019+254.5065245*exp(-3.638-.174*N)* l2^.674 = 0 I have tryed with solve(),PolynomialSystem() but without any result. I have also tryed with implicitplot() to have an approximate solution. I would be v grateful for any help. Cheers, g

Hello,

when using the graphical version of Maple 10 on Mac OS X, I frequently get problems when entering content or changing it. I start by entering content, and all works fine. Then I execute the worksheet, save the worksheet, and all is still fine.

Then I restart Maple and open the worksheet again. Now I want to change some content. But when I press shift-enter to insert a line, it does nothing the first time, and only works from the second time on... when browsing with the arrow keys, it seems like there is some sort of hidden character inserted, as I need to press the left key twice to go over it.

This topic was developed in a discussion with Mad Math. In Maple, pattern based transforms can be done using following Subs procedure

I'm converting an expression to optimized Matlab code, and some key parentheses were left out of the final expression. Is this a known bug? I'll include the offending code below:

W1 := (-5+6*b*c*d^2+5*a*b^3*c*d+5*a*b*c^3*d+a*b*c*d+a*b^3*c^3*d-2*a*b*c*d^3-4*a*b^2*c^2*d-b^4+6*b^2+6*c^2-c^4+4*d^2-2*b^2*c^2*d^2-3*b^2*c^2+3*b^4*c^2+3*b*c+3*b^2*c^4-5*b*c^3-5*b^3*c-b^3*c^3-4*d^2*b^2-4*d^2*c^2+8*a*d-8*a*d*b^2-8*a*d*c^2)/(-2*a*b*c*d+2*b*c+2*a*d-c^2-b^2+d^2)^(7/2)/(-d+2*a);

with(CodeGeneration);

Matlab(W1,optimize);

I get a final expression of

t72 = t32 + t57 / t65 / t63 / t62 / -d + 2 * a;

Could somebody send me a Maplet to solve systems of equations of any range ( linear,exponential , logarithm My e-mail is : javi36@ono.com

There is one thing which, as far as I know (please correct me if I'm wrong), you can do with other languages like FORM and MATHEMATICA, but cannot do with MAPLE. That is, to use patterns in replacement rules. If this were included in a future version of MAPLE, I wouldn't use MATHEMATICA ever again! For example, in MATHEMATICA you can write the following input: f[{a,b}] + f[c] /. f[{x_,y_}] -> p[x+y] and then you get the following output: f[c]+p[a+b] Another example, {1,x,x^2,x^3} /. x^n_ -> r[n] then you get {1,x,r[2],r[3]} The underscores are used to mean "any expression". For example, x_ means any expression to be named x. MATHEMATICA also has things like x__ (x with two underscores), which means any sequence to be named x, and x___ (three underscores) which means any sequence of zero or more expressions to be named x.

Here are the steps for making StartMaple example with Dev-C++.

1. Start Dev-C++.
2. Click File - New - Project, select Console Application, check C Project radio button and type the name of the project - something like SMexample.
3. Copy the source from ?StartMaple help page and paste it in main.c (instead of pretyped text there).
4. Click Alt+P (or Project - Project Options), go to Directories, select Include Directories and add C:\Program Files\Maple 10\extern\include there.
5. In Parameters (in Project Options) in the Compiler window type -D_MSC_VER and in the Linker window click Add Library or Object and add "../Program Files/Maple 10/bin.win/maplec.lib" .

I'm just curious - and I don't work for Maplesoft :) - but what do people here actually use Maple for ? What sorts of problems are you tackling, and what commands/packages do you typically use ? I'm also interested to hear about how people use Maple in teaching (for those that do). Myself I use Maple for research in computer algebra - mostly topics related to polynomial systems. For example, I may be trying to find algorithms to compute in new domains. I like Maple because it is very easy to program mathematical algorithms. It is not quite so easy to get them to run fast, but that gives me something to work on :) I mostly use my own software (PolynomialIdeals + recent code), but I also use the Groebner package and now the RegularChains package (new in Maple 10). I make a point of trying all the other packages every once in a while, since you never know when something is going to be useful. I use the plot commands a lot as well.