I am not able to numerically solve a non-linear PDE using "pdsolve". The problem seem to be arising due to non-linearity in the PDE. Once I remove the non-linearity (by removing a partial derivative in X below), the error goes away.
The code and the error are included below:
X:= Q(t,r)/(Q(t,r)+(0.75*diff(Q(t,r),r)));
PDE:=diff(Q(t,r),t)+X*(diff(Q(t,r),r)*1.5*(0.03-r))+Q(t,r)*r=0;
IBC:={Q(1,r)=0.01*r,Q(t,1)=10*(exp(1-t)-0.999),Q(t,0)=(exp(1-t)-1)};
ANS:=pdsolve(PDE,IBC,numeric,time=t,range=0..1,method=Box);
Error, (in pdsolve/numeric/process_PDEs) selecting function must return true or false

I'm trying to read an image into MAPLE as a matrix but I can't get the Read commmand to work. Is there some kind of working directory that I need to have the image in? Can someone give me some detailed examples on how to do this? ~Jacob

Hi, if equ:=y''+y'=9 how do can generate simulation code for maple code? on the demo "code generation"has this example. but I can't see it. thx for your help.

How do I make the evaluation of this Elliptic integral faster?
>c12:=2*sqrt(2)*int(sqrt(3*t^2-2*t*(sqrt(2)+2)+2*sqrt(2)+3)*sqrt(3*t^2*(17-12*sqrt(2))+2*t*(29*sqrt(2)-41)-24*sqrt(2)+34),t=0..1):
> evalf(c12,32);
1.5710166980738556513064017544723 -
-28
0.24579031714044391948173350026764 10 I
>
Maple generated 152 pages of equations to solve this integral.
This is how I generated this integral:
http://www.getnet.net/~cherry/derive/circle1.doc
I solved the problem using symmetric Elliptic integrals.
Maple does not support symmetric Elliptic integrals.

Can anybody help me with this: Suppose you have a small set of values data:=[0.0630, 0.1050, 0.1560] and you're wondering what's the standard deviation of data with the "old" stats package you'll get with(stats): describe[standarddeviation](data) 0.03802630668 with the new Statistics package (which is supposed to replace stats) you'll get with(Statistics): StandardDeviation(data) 0.04657252409 The stats package will assume (unless told otherwise) that it must compute the standard deviation of a population, while the Statistics package will assume that it must compute the standard deviation based on a sample.

I am using Maple 7 and displaying computations within a spreadsheet for more simple display.
One area I have been stumped with is using the if statement within a spreadsheet cell.
Something as simple as:
`if FAIL then 3 else 5 end if`

works great at a prompt but gives me a "System error," within my spreadsheet. Now, I know it recognizes the command because if I input the statement with legacy format:
`if FAIL then 3 else 5 fi`

It automatically replaces the "fi" with the new form of "end if". So why doesn't it work?
Thanks,

I am brand new to MAPLE. I have a large file full of equations which I want to put into a paper. Is there software, or a facility within MAPLE, to convert all these equations into WORD, or at least to TECH, without typing everything in again? Please respond with any help to Jerry Epstein jepstein@poly.edu

Hi, this is probably quite easy to do but quite a complicated thing to find out. Does anyone know how to plot more than one function on a graph so that for example, function f is plotted in the x-axis range from 0..10 and function g is plotted in the x-axis range from 10..100, both on the same graph. Thanks for your help.

I am fairly new to Maple 10 but not to math and graphing calculators. I was wondering if anyone knows how to get Maple to calulate a line integrals or even farther, closed loop intergals. I tried a bunch of different things with the contour integral but I dont even know if that is an operator but just a symbol instead. Thanks in advance to anyone who can help me out!

Is this a way to convert a routine in Maple internal format back to the human-readable format?

Thanks

hi, i don't know maple at all and i need to figure out how to solve this sytem of equations that model predator prey systems in maple but i get an error when i modify this code > e1 := diff(x(t),t) = k*x(t) - a*x(t)*y(t); > e2 := diff(y(t),t) = -r*y(t) + b*x(t)*y(t); to fit this equation- dx/dt = 2x(1-x/4) - xy dy/dt = -3y + xy x(0) = 1 y(0) = 1 if anyone has time to tell me what i can do to get the equilibrium points, the solution and the table of values for this system, i would be grateful

I was wondering if someone can help me solve a problem of kirchoff's law using maple, heres the problem:

Use maple and Laplace transform to find the charge q(t) on the capacitor in an RC series circuit with the following conditions; graph q(t) on the interval 0<t<6 and use the graph to estimate the time and value of the maximum charge

q(0)=0

R=50 ohms

C=.01 farads

E is a piecewise where 1<x<3 = 100, everywhere else is zero

I'm assuming that since nothing is said about the inductance in the initial conditions, L=0

heres what i got so far:

>i(t):= diff(q(t),t);

>KirchoffLaw:=E[R]+E[L]+E[C]-E[emf]=0;

Does anyone know how to go about attempting this problem with
Maple10 ?
The question is the last line in bold type, and I tried to include as much relevant information as possible.
To correct an error the second partial derivative should be with respect to time "t", not displacement z.
so it should be (1/v)*(d^2/dt^2)f(z,t).
sorry about the mistake.
thx, Dan

View 285_problem9.4Emag.mw on MapleNET or

Download 285_problem9.4Emag.mw
Hi,
How can i compute the F2 Appell Hypergeometric Function using Maple?
Can i write F2 as a function of the F1 appell function?
Thank you.
Appell Functions:
http://mathworld.wolfram.com/AppellHypergeometricFunction.html

I have a function:
fx:=5*x^4+16*x^3-24*x^2
for which to calculate roots I wish to reformulate fx to (x^2)*(5x^2+16x-24)
Which command do I need to give maple to obtain this result??
Thanks in advance