## Blank worksheets in Maple 12/linux?...

I've just installed Maple 12 on my machine running Suse 10.0, under which Maple 10 ran with no problems.  But I have two problems here: even on a newly opened worksheet, in a newly opened Maple, a simple command, such as

f:=x/(x^7+1);

takes several seconds to "evaluate", while the screen goes completely blank.  The problem is even worse if the evaluation is a difficult problem.

What seems to make it worse is if I've read in some Maple files before with

## How Can I solve a PDE system with this initial con...

I'm a primer in Maple, My problem is that I want to solve this PDE system.

PDE:= [diff(u(x,t),t)= diff(v(x,t),t,t) + u(x,t) - 1/3*u(x,t)^3 -v(x,t), diff(v(x,t),t)=u(x,t)-v(x,t)];

IBC :=  {u(x, 0) = tanh(x), v(x, 0) = 0};

pds := pdsolve(PDE,IBC,[u,v],numeric);

This gives me this error.

Error, (in pdsolve/numeric) initial/boundary conditions must be defined at one or two points for each independent variable.

## rotating an arc about a line...

I'm trying to create a football-shaped object by rotating an arc of a circle about a line.  Is there a way to define an arc in Maple?  I've been using the 3D Geometry package but I can switch to another if I need to.  I know I can calculate the arc length, but is there a way to define the arc itself as an object?  Eventually, I'd like to have the rotation of the arc and find the intersection between the rotation and another line.

Michael

## Using Units...

To all,

I am trying to carry the units through an engineering calculation; however, after loading the Units package and specifying the 'FPS' system I am not getting the results I expected.  Most likely I am at fault - syntax, format, etc. - so I have attached the worksheet in the hope that someone can diagnose the mistake (it starts in the Example 1 section).  Thank you for your assistance.

## Making Maple use the lastest JVm...

Hi

I noticed that the java virtual machine that comes with MAPLE is behing the current JVM which is installed on my system. Is there a way to make maple use my current up to date version instead of its own obsolete version ?

## Extracting components of a equation solution...

Hi all

I have trouble extracting components from of  equation solutions:

p1 := x^2+y;

e:=solve({p1}, {x});

e := {x = sqrt(-y)}, {x = -sqrt(-y)}

next I used rhs() to extract right component of the first solution

x1 := rhs(e[1]);

but I got the error:

## solve(eq,P^2) won't work and a negative sign issue...

It's a simple equation where I'm just getting maple to run through the steps.

eq:=(m+M)=a^3/P^2;

solve(eq,P^2);   returns an unexpected error

I wanted to see if maple could solve for P^2, poking here and there seeing what does and doesn't work.  I know I could just type it in, but can Maple do this?  Maybe I'm missing something.

## Avoid memory hogging...

I am using Maple 12 build 347164 for research (as a grad. student) on Windows XP.

I have written a simple block of code to do some calculations repeatedly.  However, everytime I run the code, the amount of memory Maple is using increases (3-4 MB per time).  I am simply running the code again, and the size blossoms.  I have made sure that none of my variables are expanding (e.g., a list that isn't cleared).  This is troublesome because after 30-40 runs Maple is using over 800MB and my computer has only 2GB of RAM.

## Applied Calc Help using Maple 12...

How do I enter this problem in Maple 12? I have a few like this and need to knwo how to input the equations.

1.)  Find the slope of the tangent line to the curve y=x^3+3x-8 at (2,6)

2.) The tangent line to the circle y=x^3 -6x^2 -34x -9 has slope 2 at two points on the curve. Find the two points.

3.)Find the slope of the curve y=x^5 at x= -2

## How do I get get of Complex I when intergrating...

i have Maple 12 Student edition. when i do a 5th intergration, and eval at Pi, i get a complex answer. how would i get it to display a rational answer ? h := t-> (1+t^3*cos(t))^(1/5); ((D@@5)(h))(Pi); evalf(%); simplify(%); -.1245723200-0.905070854e-1*I D1 := D(h); D2 := D(D1); D3 := D(D2); D4 := D(D3); D5 := D(D4):fsolve(D5(Pi)); -.1245723200-0.9050708540e-1*I thanks

## restricting plot3d to integers...

I'm trying to eventually make some 3d plots of some finite fields and different operations on them. Unfortunately I need some way to restrict the input to integers since apparently floor-ing them isnt enough. Heres parts of my worksheet, if it helps: G := GF(2, 8, x^8+x^4+x^3+x+1) `&*` := proc () options operator, arrow; G:-output(G:-`*`(map(G:-input, [args])[])) end proc f[1] := proc (a, b) options operator, arrow; `&*`(floor(a), floor(b)) end proc > plot3d(f[1](a, b), a = 0 .. 255, b = 0 .. 255); %;

## Buttons in Maplets...

How do I create a button that performs multiple actions? For example, I might want to create a button that both differentiates and integrates a function with one click. So far, everything I have tried has resulted in evaluating the last action in the list.

Thanks.

Cloyd

## decimal to finite field...

Hello I'm working with some finite fields(2^8) and sometimes instead of viewing/working with a polynomial its easier to work with a number. Its easy to convert from polynomial to number by just letting x=2, but is there a easy and built in way to go the other way? Thanks

## Solve numerically a system of PDEs...

Hi,

I am using Maple 11 and trying to solve numerically the following easy system of 1st order, linear PDEs: