I have this code: ade:= diff(y(r),r,r)+2*diff(y(r),r)/r+486*polylog(3/2,-exp(1-1/43*y(r))) = 0; ys:= dsolve({de, y(0) = 0, D(y)(0) = 0}, y(r), series, order=10); yn := convert(evalf(ys), polynom);yn1 := eval(yn, r = .1); dyn1 := eval(diff(yn, r)); dyn2 := eval(dyn1, r = .1);S := dsolve({de, y(.1) = 1.266393114, (D(y))(.1) = 25.18200436}, y(r), numeric);with(plots); odeplot(S, [r, y(r)], r = 0.1e-1 .. 200); # I get a plot from this step, but I need an expression for y(r) also. A crude method is to get S(1);S(2) and so on and copy paste those values for interpolation.

Good day,

Before this I've run my programme (n=2 and 3), it's ok. But now, when I run the same programme (for n=4), it's got error, why?. This is my programme.

> isom:=proc(A,B,n)

locali,j,k,s,r,eqns,t,ISM,BChange,sols,l,S1,S2,C;

C:=matrix(n,n);

BChange:=matrix(n,n);

ISM:=0;

eqns:={};

for i to n do

for j to n do

for l to n do

S1:=sum(A[i,j,k]*C[l,k],k=1..n);S2:=sum(C[p,i]*(sum(C[r,j]*B[p,r,l],r=1..n)),p=1..n); eqns:=union(eqns,{S1=S2})

end do end do end do;

sols:=[solve(eqns)];

Hello

Given following list:

vec := [[`@`(1, {.34}), `@`(2, {.4})], [[], 1], [[], 2], 3];

Applying the indets function to vec[1] yields

indets(vec[1], numeric);
              {1, 2, 0.34, .4}

Given a list where we have identical elements (in this case the floats)

vec := [[`@`(1, {.4}), `@`(2, {.4})], [[], 1], [[], 2], 3];

The following yields

Hi all,

I have Maple 13, and I am learning how to use it.

To start with it, I was trying to resolve the values of X and Y in the following equations:

(1): X + Y = 60

(2) X = Y -12

and here were what I input into Maple

matlab has the following command:

axis ([-inf inf -inf inf])

where the inf means (something like) "the largest value" and -inf "the smallest value". With this command, you can set the dimension of the axes without having to enter the actual values, which is then robust to changes in parameter values. This is most useful in situations where some of the values are to be fixed and others left to the simulation, say:

axis ([0 inf -inf 1])

What would be the Maple equivalent or workaround?

many thanks.

Hi acer,

I got the problem of "Int vs int" again. With your advice, I changed from "int" to "Int" in the f2 expression below and draw the graph

However, the "memory allocation failed" message appeared again after long time running. Did I understand something wrong?

Here is the expression I want to draw the 2D graph

f1:= d*exp(-(0.5*(u-s-k))^2-(0.5*(u-s-k)+t-u)^2+(0.5*(u-s-k))^2+(-d*k));

Hello,

I've seen a topic or two similar to what I'm trying to do, but not exactly the same.  Their solutions didn't work for my issue.

Long story short, I need a function plotted on a loglog scale with certain points on this curve to be actual points, just like a scatter plot on top of a function.  Let's assume I've got a function f(x) and I have a list of some values for x.  I'd like a loglog plot of f(x) as well as points for each of my 'x' values to be actual points that lie on f(x).

Hi all, I solved this nonlinear DE de := diff(y(r), r, r)+2*(diff(y(r), r))/r+9*(16*43)*Pi^2*sqrt(Pi/(2*(1/43)^3))*polylog(3/2, -exp(1/43*(43-y(r))))/(16*Pi^2*sqrt(43)^3) = 0; with initial conditions y(0) = 0, D(y))(0) = 0 by using truncated series method in 'solve symbolically' option (Dsolve[interactive]). I am getting a solution like this: y(r) = -(3/4)*sqrt(86)*sqrt(Pi)*polylog(3/2, -exp(1))*sqrt(43)*r^2-(1161/80)*Pi*polylog(1/2, -exp(1))*polylog(3/2, -exp(1))*r^4+O(r^6). How can I get an asymptotic potential y(r) for r-> infinity? Thank you MS

Dear All,

   i want to used optimizatiom method in Maple ( Paritcal Swarm optimization) , i have the algorithm but i can to write the codes in Maple, vuold any one help for that.

      Thanks and best regards.

 

Ahmed

 

 

Hi all, I have this same equation in another active thread also with boundary conditions. But now I have INITIAL CONDITIONS INSTEAD. I thought of just starting a fresh post. Here is my non-linear differential equation x := diff(y(r), r, r)+2*(diff(y(r), r))/r+ C*polylog(3/2, -exp(C2*(C3-y(r)))) = 0 with boundary values D(y)(0)=0 and y(0)=0. C, C1 and C2 are some numbers. The hint says to use procedure to solve polylog and then integrate the differential equation. I was wondering if I can get some advice on solving this equation.

Isn't there a way to get Maple to document each step in its execution of a command?  E,g,, I have a complicated expression that I want to SIMPLIFY & I would like to see how Maple does it.

Alla

I want to evaluate an integral over a numerically calculated function. Specifically:

Hello everybody,

Im trying to plot a f (x) function but maple keeps giving me an empty plot error.

From my maple worksheet:

Error:

I recently realized that maple/standard has some plotting capabilities not available in maple/classic. I nevertheless plan to stick with classic except for the occasional printing of graphs. I don't want to write multiple worksheets, so I want my worksheet to know when I'm printing in standard and when I'm printing in classic. I don't want a maple/classic plot to overwrite a maple/standard plot (and vice versa). I want to set some classic-specific and standard-specific options.

I have an equation of a line that intersects the ellipse.  I can get Maple to find one intersection.  How do I get the other?

E1:=x^2/300+y^2/1000=1;

E2:=y=2*x+40;

solve({E1,E2},{x,y});

evalf(%);

gives me {x=-4.810723698, y=30.37855260}

or I could use fsolve({E1,E2},{x,y}); and get the numeric result right away. 

There is a second intersection point I can find graphically around x=-5 y=30 but I don't know how to get maple to find it numerically.