I'm trying to do some differential geomery calculations and they are becoming outrageously large.  I'd like to use Maple's differential geometry package (tensor package), but it seems incapable of performing the calculations in an arbitrary number of dimensionis (i.e. with a fixed but arbitrary number of dimensions).  Does anyone know of a good package or tool to use for such work?

 

Hello,

 

Whenever I use the compiler in Maple 12 ...I get an error message that it cannot create a directory becuase of write permissions.  I have opened up all permissions that I can think of.  Am I missing something ??

 

Thanks

Hi, I am using the Rootfinding Isolate function to solve a system of polynomial equations. It works very well most of the time but ocasionally I get the following error message:

Error, (in RootFinding:-Isolate) Limit for allocations (1-->1000): in update_all_garbages !

Does anyone know what this means? - I assume it has something to do with the memory allocation.

Any ideas on how to prevent this error?

Thanks

Steve

Hellooo!

I'm Working with this document (I attach it)

When I use with the right-click button the replace unit command in the last formula.....in the file it's  2389.194 kg/m replaced to units          t/m      and then save, maple crashes...why???

 

Hi,

I am developing a set of ODEs and constraints to be solved using the dsolve(MoLSYS, numeric, method=rosenbrock_dae).  The smallest system that I can set up to test my program is 3500 functions X 3500 equations.  Unfortunately, dsolve doesn't return any result or error of any kind, even after an hour.  Can anyone here please tell me the practical limit on the number of functions/equations that the DAE solver can handle?

Thank you,

PGK

 

A modified "elements" of group Package:<a href='http://www.mapleprimes.com/files/1512_elements.txt'>elems</a>
This proc "elems" can not only generate the elements of a permutation group but also show you every element's factors.

In this previous post, an example is shown that demonstrates the potential problems that can arise following symbolic conversions such as from sqrt(x^2)  to x^(1/2).

Here x is an unknown symbol. The difficulties include the fact that, while `sqrt` can be smart about simplifying numeric values (eg. integers, rationals) the `^` operator has no such opportunity. Once the conversion from `sqrt`...

W := (81/539)*42^(1/2)*hypergeom([-1/2, 3/8, 169/88], [81/88, 19/8], -1/6): evalf(W,50); 0.99999999999999999999999999999999999999999999999996 Show W is 1

> q := x^(1/2):

> type(q, `^`);
                                     true
> op(0,q);
                                       ^

> subsindets(q, `^`, f->subsop(0=H,f));
Error, (in unknown) improper op or subscript selector

What's wrong with that last one? It's modelled on the first Example in the ?subsindets help-page.

Are there cases where...

Dear all, I am working with Maple 11 and 12 on an Intel Mac running Leopard, and I am having trouble with a very simple script that keeps telling "kernel connection lost"; see below. > restart; with(CurveFitting); > poly2 := proc (x, u) return PolynomialInterpolation(x, u, z) end proc; proc(x, u) ... end; > getArrays := proc (left, right) local x, u; x := [seq(h*i, i = left .. right)]; u := [seq(u[i], i = left .. right)]; return x, u end proc; proc(left, right) ... end; > x, u := getArrays(-2, 2); [-2 h, -h, 0, h, 2 h], [u[-2], u[-1], u[0], u[1], u[2]]

I have recently wanted to work with finite groups of small order in Maple. Some other packages, such as GAP, allow one to easily work with any finite group of size up to 2000. As far as I can tell no such capability existed for maple so I have tried my hand at my first package, "tinygroups," which is basically a list of all of the nonisomorphic groups of up to 60 elements. It can be obtained here:

http://www.math.uwaterloo.ca/~dagpritc/math/tinygroups/

So what should i mod 0 really be equal to?

I understand that isolve doesn't work with inequalities, at least it is not mentioned on the isolve help page. Still, the following seems strange,

isolve({40*a+60*b<=150, a>=0, b>=0});

                             {b = _NN1~}

It is related to that post.

Alec

PS By the way, some of such problems that Maple can't solve, are not even high school problems - they are an elementary school (and maybe even kindergarten) problems. -Alec

Hi all,

I'm trying to solve linear programs on Maple 11, but it is not giving me an answer. Have I made a mistake? The comand I used is:

with(Optimization):

LPSolve(40*a + 60*b, {40*a + 60*b <= 150}, assume=nonnegint, maximize)

and maple returns:

"Warning, problem appears to be unbounded".

 

But in Maple 10, this same comand works perfect. Does someone know why Maple 11 doesn't??

Mario

I was working on this fairly short equation. The solution gives different results in Maple 11.01 and 11.02:

> solve(0.981747e-8*RR+0.16549e-34*(1/RR^3-1/(0.50e-9+RR)^3)+(0.44e-26*(1+0.127324e10*RR))*10.000^2/RR^2 = 0., RR)

The equation has 7 solutions, of which 3 are real, one of which is for example -9.959429517E-10. The correct value is negative, however Maple 11.01 (build 296069) gives 9.959429517E-10, while Maple 11.02 gives -9.959429517E-10.