i'm using maple 15 and trying to solve the following PDE without success, can you help please.

(ab+(a*sin(x1))^2-(c*cos(x1))^2)*d/dx1(V(x1,x2))=-dsin(x1)/exp(x1).

where a,b,c and d are constants. and i need it to be solved as a PDE please.

thank you,

Mutaz

hello,everyone,
I have a problem to make a figure, commands are below:

restart;
1+(2*(S1*e2/(S2*e1)+S2*e1/(S1*e2)))*tanh(S2*k*d);
S1 = sqrt(beta^2-e1), S2 = sqrt(beta^2-e2);
e1 = 4, e2 = -19-.53*I;
subs(`%%`, %, k = 2*Pi/(0.633e-6), `%%%`);

I want to plot the relation between d and beta(real part named betar and imaginary part betai),but meet some trouble.
I got some points from the article is when d=400e-10, betar in the range (2.1,2.2...

Is there another way to plot 3d intensity levels in an image?  Using matrixplot takes a long time. 

restart;gc():
with(ImageTools):
with(plots):

a:=Read("c:/lighthouse1.jpg"):
b:=convert(ToGrayscale(a),Array):
c:=convert(b,Matrix):

matrixplot(c,style=point,shading=zhue)

martixplot(c,style=point,shading=zhue,orientation=[0,0])

The operation: 2^29.403243784 gives me 7.0999999820*10^8.

However, using WolframAlpha, the answer is 7.10000000139658667836958142950829925944726171959 × 10^8.

These are 2 different answers. Can someone offer an explanation as to why this occurs and how I can avoid this problem?

Thanks in Advance!

Eddy Liu

Good morning everbody,

I am currently trying to get string and numerical datas from a txt.file but I don't get how to do this.
I have done this in matlab but I would like to make it in maple.
I have read other post about the subject and try tried this command:

 fd := fopen(dataFile,READ,TEXT):
    theData:=readdata(fd,string, 3): # 3 columns
  fclose(fd):

  A:=convert(theData,Array);

but it didn't help me. 

Hi , 

 u(t-n*Pi)=0 if (t-n*Pi)<0

 u(t-n*Pi)=1 if (t-n*Pi)>=0

need to plot y(t) against t where t=0..30:

y(t)=sum(sin(t-n*Pi)u(t-n*Pi),n..infinity)

I appreciate 

How should I save my result-expression so as to be able to use it directly in other file without having to generate it again.

please help
regards,

Hi,

My work requires me to use derivative a lot. Especially, the partial one. Given F(x,x_dot). Maple has this partial expression, however I'd like to partial differentiate F with regard to x_dot (the derivative of x over time).

Is this possible? If possible, please tell me how.

Thank you.

Abe

i had a 15 set of nonlinear PDEs,i convert them to nonlinear set of ODEs, i try to solve them using the command dsolve(numeric) , but when solving i face this erroe :

Error, (in DEtools/convertsys) numeric exception: division by zero

what should i do?the problem is in my equations ? or what?

with regards,thnx. 

Hello, 

I'm importing some other modelica models from other softwares (like open-modelica and dymola) inside maplesim. I can work in a full compatible code, except for the lookup table. Some of the models I'm importing as a library uses the standard lookup tables (not the ones given by maplesim) - I tried to run those standard lookup tables (from the modelica library) in maplesim, but it does not work.

Is there a way to solve...

A wonderful plot I have found created by Matthius Kawski in Maple 8.  But newer versions creates an Error, (in f) unsupported type `complex(float)` in evalhf in the DEplot.  Can someone fix the error?  Worksheet is attached.

lyap-not-proper.mws

I have this csv file on my website (the file is hosted on dropbox.com) that I want to load into Maple:
Hence I type:

URL := "https://dl.dropboxusercontent.com/s/7fqalrdtn0c3r8u/Stockholm%20Stock%20Exchange%28Percentage%20Change%29.csv?token_hash=AAGxpzva90O6oNlLAie3T1h0UNP06I5EPg2qrROHMglRMw&dl=1":
HTTP:-Get(URL, 'timeout' = 100)

Then I get:

Error, (in HTTP:-Get) timed out waiting for initial response from server

If you past the url into...

Here is a relation: t[n+1]:=((a*n^2+a*n+b)*t[n]+c*(n^2)*t[n-1])/(n+1)^2

t[-1]:=0 and t[0]:=1

a,b,c are integers and a,b,c are from 1 to 20 and n is from 0 to 20

the series t[n+1] is integer

I want to know how to list (a,b,c) that satisfies the above. Please help!

I was using the Finance package and used the command ImpliedVolatilitySurface(...). But it is showing the following error 
"Error, (in Finance:-ImpliedVolatilitySurface) external linking: error loading external library finance.dll: The specified module could not be found."Please help..

After solving a system of differential equations I got module. So I have a solution for the functions U1 (x, t) and U2 (x, t). Please tell me, how do I now get x * which corresponds to U1 (x *, 10) = max?Help please.