Hi everybody and thanks a lot for your help!

My problem is the following: I would like to draw a phase diagram for a system of 3 differential equations. So far this is not a problem but I would like to have the arrows of the vector field included in the diagram, like it is possible for systems of 2 diff. equations. Is that possible?

I use DEPlot3d, I suppose that is the correct tool?

Thanks and regards

Hans

I have the above program

S1:=unapply(u*FresnelS(u)+((1/Pi)*cos((1/2)*Pi*u^2))-(1/Pi),u);

C1:=unapply(u*FresnelC(u)-((1/Pi)*sin((1/2)*Pi*u^2)),u);

R1:=1;

u1:=evalf(sqrt(0.4));

E1:=evalf(Pi*R1*S1(u1)+R1);

D1:=evalf(Pi*R1*C1(u1));

with(plottools);

with(plots);

c1 := circle([D1, E1], R1);

a:=evalf(Pi*R1*u1);

plot([a*FresnelC(u),a*FresnelS(u),u=0..u1]);

p1:=plots[display](plot([a*FresnelC(u),a*FresnelS(u),u=0..u1]),c1,scaling=constrained);

p3:=plot(0,x=-1..0);

display(p1,p3);

I have found eigenvalues of a  2x2 matrix A, these are displayed in a vector. eg.

a + sqrt(b)

a - sqrt(b)

Is there any way I can write code which will find the difference between them? At the moment I'm doing it manually and it is taking a lot of time as I have many matrices.

Hello
Yesterday I was playing around with the Tolerances package in Maple 12. To familiarize myself I with it I tried to work out the equivalent resistance of two parallel resistors with tolerances.
R1:=80.0 +/- 4.0 [Ohm]
R2:=120.0 +/- 6.0 [Ohm]
Maple returned: Req:=R1*R2/(R1+R2) = 48.5 +/- 7.22 [Ohm]   (rounded values, there is some weirdness going on with this also.)
The right answer should be 48 +/- 2.4 [Ohm].

Dear Maple users

I read somewhere that plots with units is new in Maple 13. There is however something which is not working well:

> restart:
> T:=30 [[year]]:
> A0:=370000[[Bq]]:
> A(t):=A0*(1/2)^(t/T):
> plot(A(t), t=0..100[[year]])

I expected to see a plot of an exponential with units. A coordinate system was displayed but no function plot!! Can someone explain why? If I remove the units, the exponential appears!

Regards, Erik V. 

Download 16210_convection1.mws
View file details

I am try to write the solution in latex but its too long. Can any one help me to use some maple commads to write the solution in a compressed form.

Thanks

Hello,

 

I've got a big file "file.mw" written in Maple12, which is OK, since I own Maple 12. Unfortunately it is totally in Math mode and all in one single group, i.e. of the form

 

> first line;
   second line;
   third line;
   ....

   last line;
>

 

(keep in mind that there are only two ">" s).

I have maple 13 for Mac OS X version 10.6.2. Initially maple worked fine but suddenly it didn't seem to recognise keyboard shortcuts. Then when saving a worksheet all it did was save a blank one. Later it threw out a couple of two dimensional blue lines when using PDEplot. And recently it won't export any plots. In short maple is even wore than windows (and thats saying something).

Dear Friends,

I have Maple v9.5 on my laptop. I would like to know how to take the inverse cosine and sine transform of a function.

Since I am using Integral Transformation to solve PDEs, it is of great importance to me.

Best,

Maziar

How can I round off the numbers in a random array or matrix?  Round or Trunc will not work on a random number.

with(ArrayTools):
a:=30*(ArrayTools:-RandomArray(8,8));

 

I replied to the following thread but after further thought I probably start a new thread:

http://www.mapleprimes.com/forum/multivariate-directional-derivative-0

hey all

I want to write an algorithm similar to this but instead of ''w1:=a+h''   I have to put about 75 commands. how can i do this?

 

Can someone help me please?

 

Hello all!

I am an Open University student just starting with Maple 11. I am studying the course MS325 Computer Algebra, Chaos and Simulations and we have to use the classic interface.

I use Fedora 11 Linux on my Acer Aspire One netbook. I have loaded Maple 11 for Linux, and the standard version opens OK by using ./xmaple

But if I try to open the classic interface with ./maple -cw

I get this:

I know it is possible to change the "Look and Feel" of Java applications, and i was wondering if there was any way to do this on Maple? (Maple 13 for Linux, to be exact.)