Hi,

I’m trying to animate the volume generated by rotating the function curve around the Ox axis. the Solidofrevolution command with animation output generate a disk volume

Thanks

QuestionAnimationVolumeOfRevolution.mw

I am solving coupled PDEs under various BCs and ICs on the (x,t) domain, to obtain momentum p((x(t),t) solution plots of the within a MAPLE worksheet. 

However, I am getting JAVA memory overload (> 2GB), which brings MAPLE to a halt when plots are displayed in the worksheet.  Is there a way of writing the graphical plots directly to a file on my computer, so that the plots can later be view separately on my computer screen, thus avoiding JAVA memory overload within MAPLE.

If this is possible, please could someone send me MAPLE code to create external plots...perhaps using simple examples in MAPLE?

Melvin .

with(DEtools); with(plots); with(plots, implicitplot);

LC := [diff(x(t), t) = x(t)*(1-x(t)^2-y(t)^2)+y(t)*((1-x(t))^2+y(t)^2), diff(y(t), t) = y(t)*(1-x(t)^2-y(t)^2)-y(t)*((1-x(t))^2+y(t)^2)]

p1 := DEplot(LC, {x(t), y(t)}, t = 0 .. 100, [x(0) = 1, y(0) = 1])

Error, (in DEtools/DEplot/CheckInitial) too few initial conditions: [x(0) = 1]

Download mm.mwmm.mw

Hello,

I am trying to generate a compiled c function

dc_test := proc( a :: Array(datatype=float[8]), b :: Array(datatype=float[8]), c :: Array(datatype=float[8]) ) 

c[..,..] := a . b;

return 0

end:

cdc_test:=Compiler:-Compile(dc_test, optimize):

a := Array(1..2, 1..2, fill=1.0, datatype=float[8]);
b := Array(1..2, 1..2, fill=1.0, datatype=float[8]);
c := Array(1..2, 1..2, datatype=float[8]);
                           
dc_test(a, b, c);

cdc_test(a, b, c);

This doesn't work because it doesn't recognize the "." symbol. Also if I were to take the transpose, for example Transpose(a), then it doesn't recognize that either. Are there commands for this that I'm unware of or do you have to program them from scratch?

Hi,

How to animate a plot with Shadebetween command?

Thanks

AnimationShadebetween.mw

Hi, I am currently working with Maple on school, and I wanted to use the diff(); function to find the partial derivative with respect to x. Anyways; I noticed when I was not using the multiplication sign I got the answer 0 as seen below:

diff(2*sqrt(xyz), x) = 0

But when I used the multiplication sign as seen (x*y*z instead), I got the correct answer.

diff(2*sqrt(x*y*z), x) = y*z/sqrt(x*y*z)

Why so?

Thanks,

Adrian

hi daer 

i am trying to run the following but error came 

acually the boundry conditions are periodic

x=linspace(0,1,50);
t=linspace(0,1,50);
m=0;
eqn=@(x,t,u,dudx)transistorPDE(x,t,u,dudx,C);
ic=@(x)transistorIC(x,C);
sol=pdepe((m,eqn,ic,transistorBC,x,t);
function [c,f,s]=transistorPDE(x,t,u,dudx,C)
a=0.1;
c=1;
f=0;
s=-a*dudx;
end
function u0=transistorIC(x,C)
L=1;
u0=exp(-(x-L/2)^2);
end
function [pl,ql,pr,qr]=transistorBC(xl,ul,xr,ur,t)
pl=ul;
ql=0;
pr=pl;
qr=0;
end
 

Hello Everyone

I have solved the equation below numerically and now I want to integral p(x)

ode := diff((b+5)*((1/6)*(diff(p(x), x))*h^3+(1/2)*c*h^2)/(b+2)+De^2*((1/10)*(diff(p(x), x))^3*h^5+c^2*(diff(p(x), x))*h^3+(1/2)*c*(diff(p(x), x))^2*h^4+c^3*h^2)/(b+2), x)+diff(h, x) = 0

ics := p(0) = 0, p(1) = 0;
                   ics := p(0) = 0, p(1) = 0
solnum := dsolve({ics, ode}, numeric, method = bvp, maxmesh = 600);
                solnum := proc(x_bvp)  ...  end;
odeplot(solnum, 0 .. 1)

but when I write evalf(int(p,0..1)) I get this result:. What should I do to have the value?

Dear Users!

Hope you would be fine with everything. I want to evaluate an expression (diff(u(y, t), y)+diff(diff(u(y, t), y), t)) for various values of b at y = 0, t=1. Please help me to evaluate it. Thanks in advance,

restart; with(plots); a := .7; L := 8; HAA := [0, 2, 5, 10];

for i to nops(HAA) do

b := op(i, HAA);

PDE1[i] := diff(u(y, t), t) = diff(u(y, t), y, y)+diff(diff(u(y, t), y, y), t)-b*u(y, t)+T(y, t);

PDE2[i] := diff(T(y, t), t) = (1+(1+(a-1)*T(y, t))^3)*(diff(T(y, t), y, y))+(a-1)*(1+(a-1)*T(y, t))^2*(diff(T(y, t), y))^2+T(y, t)*(diff(T(y, t), y, y))+(diff(T(y, t), y))^2;

ICandBC[i] := {T(L, t) = 0, T(y, 0) = 0, u(0, t) = t, u(L, t) = 0, u(y, 0) = 0, (D[1](T))(0, t) = -1};

PDE[i] := {PDE1[i], PDE2[i]}; pds[i] := pdsolve(PDE[i], ICandBC[i], numeric)

end do;
 

Here's the recurrence equation I'm trying to solve and the weird answer that Maple 2018 gives me on Windows 10.

Answer which I easily improved.

Hi,

I would like to determine if some lengthy expression F is linear in one of its inderteminates X.
 I use to use type(F, linear(X)) to do this but I've just found that if F is piiecewise defined, then type(F, linear(X)) returns false even if E is linear in X...
For instance, let  F := a*X+piecewise(Y<0, X, b)
then type(F, X) returns false.

I do not pretend it is a bug: at first sight I would say that F is linear with respect to X but maybe the notion of linearity with respect to an indeterlinate must be interpretated as "linear on each branch" ?

For the moment I've circumvented the problem by doing this :
dF := diff(F, X):
has(dF, X): # returns {\emptyset} if F is linear in X
 

But, as I said, F can be a rather lengthy expression invoking a lot of piecewise constructors, and I don't think that computing dF is an efficient way to do the job.

Do you have a better idea to proceed?

Thanks in advance

Greeting for all members in Mapleprimes

could I have a simple procedure to plot the following figure

See the attached file.

Amr

Squares.mw

If

p_{x} = a*p + u*q;    (1)

q_{x} = -conjugate(u)*p - a*q;  (2)     # where a is complex parameter, p_{x} mean derivative of p w.r.t x

Define, u=p^2+conjugate(q)^2,  (3)  

Now take the derivative of (3) w.r.t x and by using (1) and (2), we get

 u_{x}=2(a*p^2 - conjugate(a)*conjugate(q)^2) + 2*(p^2 + conjugate(q)^2)*(p*q - conjugate(p)*conjugate(q)).  (4)

How to calculate the results (4) on maple?

123.mw

Hollo evreyone,

Can you help me to plot the functions given by the pdf attached file.

N.B : One can take theta=pi.

Best regardsplot.pdf

I have a list and I would like to generate all the permutations of that list deterministically and sequential. All I have found is shuffle which may duplicate results(of course I could track this to avoid dups but it should be overkill and slow and consume lots of memory).