## How to plot3d of nonlinear couples eqs...

Here is my code:

t := 6*Pi; lambda := .1; N := 5; M := sqrt(N(N+1))*exp(I*phi); omegap := 1

eq1:=-2*(n(phi,delta)-N)+(u(phi,delta)-M)*exp(-2*I*omegap*t/lambda)+((z(phi,delta)-conjugate(M))*exp(2*I*omegap*t/lambda)):
eq2:=-2*(1-I*delta)*u(phi,delta)+2*(n(phi,delta)-N)*exp(2*I*omegap*t/lambda)+2*M:
eq3:=-2*(1+I*delta)*z(phi,delta)+2*(n(phi,delta)-N)*exp(-2*I*omegap*t/lambda)+2*conjugate(M):
convert(eq1, rational); convert(eq2, rational); convert(eq3, rational);

f1:=evalc(eq1);f1:=evalc(eq2):f3:=evalc(eq3)
f1 := solve{f1, f2, f3};
with(plots); Impliciplot3([n(phi,delta)], delta = -10 .. 10, phi = 0 .. 2*Pi);

## Two apparently identical symbols but evalb says th...

Hi,

I work with a parameterized ODE whose numerical solution is called sol.
The names of the parameters I get from sol(parameters) are not the same as the initial names I used.
I've been stuck on this problem for more almost two hours and I can't find out if I made a mistake or if it's a Maple problem.

 > restart
 > interface(version);
 (1)
 > sys := { M__p * diff(x(t), t) = K*x(t), x(0) = 0};
 (2)
 > params := [M__p, K]; sol    := dsolve(sys, numeric, parameters=params);
 (3)
 > data := [params[1] = 10., params[2] = 10000.]; instance := sol(parameters=data); whattype(%);
 (4)
 > lprint(data); lprint(lhs~(data));
 [M__p = 10., K = 10000.] [M__p, K]
 > lprint(instance); lprint(lhs~(instance));
 [M__p = 10., K = 10000.] [M__p, K]
 > zip((u,v) -> evalb(u=v), lhs~(data), lhs~(instance))
 (5)
 > zip((u,v) -> evalb(u=v), params, lhs~(instance))
 (6)
 > zip((u,v) -> evalb(u=v), params, lhs~(data))
 (7)
 >

## coupled partial differential equations...

Hello,

I have a problem with PDE coupled that I don't know how to solve in the maple.

Are there some analitical/numerical methods to solve the problem?

Any help will be usefull!!

## Unable to get correct interval for ...

I'm trying to find the interval of convergence for the sum

sum((x-2)^n/((x-2)^n),n=0..infinity)



c:=n-> 1/(n^2-1)
c := proc (n) options operator, arrow; 1/(n^2-1) end proc

s:=x-> sum(c(n)*((x-2)^n), n=0..infinity)
s := proc (x) options operator, arrow; sum(c(n)*x^n, n = 0 ..

infinity) end proc

# figure out how to plot this, without making it crash
abs( (c(n+1)*x^(n+1)) / (c(n)*x^n) );
| (n + 1) / 2    \|
|x        \n  - 1/|
|-----------------|
|/       2    \  n|
|\(n + 1)  - 1/ x |

simplify( % );
|  / 2    \|
|x \n  - 1/|
|----------|
|n (2 + n) |

L:= limit( %, n=infinity );
L := |x|

solve( L<1, x );
RealRange(Open(-1), Open(1))

simplify( s(3) )
infinity



How do I get it to find the correct interval, which is [1,3] I get the correct radius, which is 1.

## add latex package for Maple...

I'm able to export Maple documents as LaTeX, but I'm not able to execute them because I can't find the package in

{maplestd2e}

in MikTex.

How do I add this package to MikTex, and by extension, TexnicCenter?

## For the Latex code for a Matrix...

For the Latex code of matrix B, I used the following procedure. But the last column of B is not what we're looking for in the latex code. (There is no problem in the other columns)

restart:
interface(rtablesize=20):
f:=(x,t)->x*t;
g:=(x,t)->x^2*t;

B:=Matrix([[x,t,"f(x,t)","g(x,t)"],
seq(seq([i,j,f(i,j),g(i,j)],
j=0.125..0.875, 0.25),
i=0.125..0.875,0.25)]):
B[1,..]:=map(p->nprintf(#mi(%a);,p),B[1,..]):
B[2..,4]:=map(p->nprintf(#mn(\"%1.2e\");,p),B[2..,4]):

Lat:=proc(M::Matrix,
{output::{NoUserValue,identical(string)}:=':-NoUserValue'})
local m,n,S;
(m,n):=op(1,M);
S:=cat(" \\begin{tabular}",
"{|",seq("c|",i=1..op([1,2],M)),"} ",
"\\hline ",
seq([seq(sprintf("$%s$ & ",latex(M[i,j],':-output'=string)),j=1..n-1),
sprintf("$%s$ \\\\ \\hline ",latex(M[i,n],':-output'=string))][],i=1..m),
"\\end{tabular} ");
if output=':-string' then
return S;
else
printf("%s",S);
return NULL;
end if;
end proc:
Lat(B);