MaplePrimes Questions

Hi,

do anybody know, how I can see how a function is programmed? I want to know more about dsolve function and what is hidden behind.

Thank you all

Hej all,

I have a problem. When i have a 9-1 vector "DD" how can i get maple to solve DD^2 my equation is A=(pi/4)*DD^2 should be simple.

 

Also when i have two vectors one is 9-1 and the other is 5-1 i want to divide the 5-1 / 9-1 but i want all possible soluitons? not just 5 results but 45 results.(the zip fuction only gives me 5 results)

 

Pls help 

 

Kind regards

Howdy!!

Just thought I'd put a quick one in. I'm trying to solve the Schrodinger equation given as:

schro := {diff(psi(x), x, x)-((b^2-a*(2*p+3))*x^2+2*ab*x^4+a^2*x^6-energy)*psi(x) = 0};

under the constraint

energy=(2p+1)b

I'm trying to plot this for a range of values of the parameters a,b and fixed p=0,1.

I'm aiming to get a solution of the form

psi(x)=(x^p) exp((-a(x^4))/4)-(b(x^2)/2)

and plotting it.

Thanks in advance

I wish to compare five letter words in a list of 5 letter words with a string like "*e*d*".  The asterisks represent unknown letters; the e and d, known letters.  I wish to compare this string with each word in the list and discard any words which do not match.  I would end up with a list of matching words eg ["fends", "sends", . . .]   Is there a string function to compare partial matches?  I've looked at the compare and match commands,  but they don't seem applicable.

   Any suggestions would be most appreciated.

Regards, David 

I copy a program from a book and try to run it, but when i try to run it return:

too many levels of recursion

Here is my program:

Hope every one can help me solve this problem. Thank!

I am trying to solve in Maple the system 
d{x}/dt =(1  1 \\1  -1).{x}
with initial conditions {x(0)} =(1 \\ -1),
where {x} is a vector.


This is what I did up to now


with(DEtools):
M1:=<1,1;1,-1>;
matrixDE(M1,t);
FM:=matrixDE(M1,t)[1];


but I am not sure how to correctly input the initial conditions to find a solution to the problem. I would appreciate any help provided.
 

In a trajectory. How can i return the range if i know the position-function. ... return x when y=0?

Recently I have used a FilterForge filter to generate hyperbolic tiles from images (Lua code with Möbius transform etc. available). If an input image (1 see below) is selected a tile (2) is generated if the hyperbolic parameters (5,3,2) were chosen.  How could this be made with Maple?

 

The origin of this problem is that I want to bound a norm below. After som assigning of variables etc it boils down to minimizing;

S(x,y,z,w,A,B,E,F,G,H):=A*x^2+A*y^2+B*x^2+B*y^2+(-E*G+F*H+1)*x*z/(1-2*E*G+2*F*H+(F*H)^2+(E*G)^2+(E*H)^2+(F*G)^2-4*E*F*G*H)+(-E*G+F*H+1)*y*w/(1-2*E*G+2*F*H+(F*H)^2+(E*G)^2+(E*H)^2+(F*G)^2-4*E*F*G*H)-(-E*H+F*G)*y*z/(1-2*E*G+2*F*H+(F*H)^2+(E*G)^2+(E*H)^2+(F*G)^2-4*E*F*G*H)-(-E*H+F*G)*x*z/(1-2*E*G+2*F*H+(F*H)^2+(E*G)^2+(E*H)^2+(F*G)^2-4*E*F*G*H)-6*E*x+6*F*y-6*G*z+6*H*w

I first treat the x,y,z,w as coefficents and optimize over them( these are real and imaginary parts of complex parameters of my norm which on paper is a sum).
I use standard way to get the minia w.r.t these 4 variables via "solve". Then I put the solution into the a new function N(A,B,E,F,G,H) and try to optimize that with NLP and get one solution, but this is only local and it has the following message attached to it;

"Warning, no iterations performed as initial point satisfies first-order conditions"

I want a global minima for my polynomial N in 6 variables and I have some constarints on them aswell. Furthermore I put all variables to be real.

What command or package can I use to get this?

How to put programmatically 2 dots above the first and the last digit  as in the example?

http://s017.radikal.ru/i419/1610/55/958cd75b6b34.png

 

Since the new editor for some reason I cannot upload any pictures or files from my computer.

 

Previous year I was using Maple 2015 and I had a procedure in which I had used

A := Array((1 .. 3)$3);

And similar use of $. This year I'm using Maple 2016. Now I came back to my old procedure but Maple doesn't compile the procedure anymore and instead shows

Error, `$` unexpected
What is the problem? Is something changed in new version of Maple?

Why I use Array and $ is my old question here http://www.mapleprimes.com/questions/210628-Undefined-For-Loop-Bound which was fine before.

Hi all, I need a heep to solve 6 PDEs from the first order with initial and boundry conditions.

Here is the file PDE_with_IBC-BC.mwPDE_with_IBC-BC.mw

Hi,

The error "warning bad name, cannot profile...." occurred and I don't know why. Here my minimal example,

test.mw

Does anyone knows the reason?

 

> restart; for j to nops(n) do sys := diff(f(eta), eta, eta, eta)+f(eta)*(diff(f(eta), eta, eta))+1-(diff(f(eta), eta))^2 = 0, (diff(diff(theta(eta), eta), eta))/pr+f(eta)*(diff(theta(eta), eta))-(diff(f(eta), eta))*theta(eta) = 0; bcs := f(0) = 0, (D(f))(0) = l+b*((D@@2)(f))(0), (D(f))(-.5) = 1, theta(0) = 1+s*(D(theta))(-.5), theta(2) = 0; n := [1, 2, 3, 4, 5, 6]; pr := .71; p := 0; q := 0; b := 0; l := 0; s := 0; L := [red, blue, orange]; R1 := 2*n[j]/(1+n[j]); R2 := 2*p/(1+n); p := proc (f1, th1, { output::name := 'number' }) local res1, fvals, thvals, res2; option remember; res1 := dsolve({sys, f(1) = 0, theta(0) = 1+th1, (D(f))(0) = f1, (D(theta))(0) = th1, ((D@@2)(f))(0) = f1-1}, numeric, :-output = listprocedure); fvals := (subs(res1, [seq(diff(f(eta), [`$`(eta, i)]), i = 0 .. 2)]))(0); thvals := (subs(res1, [seq(diff(theta(eta), [`$`(eta, i)]), i = 0 .. 1)]))(0); res2 := dsolve({sys, f(0) = fvals[1], theta(0) = thvals[1], theta(5) = 0, (D(f))(0) = fvals[2], (D(f))(5) = 1}, numeric, :-output = listprocedure); if output = 'number' then [fvals[3]-(subs(res2, diff(f(eta), `$`(eta, 2))))(0), thvals[2]-(subs(res2, diff(theta(eta), eta)))(0)] else res1, res2 end if end proc; p1 := proc (f1, th1) p(args)[1] end proc; p2 := proc (f1, th1) p(args)[2] end proc; p(.3, -.2); par := fsolve([p1, p2], [.3, -.2]); res1, res2 := p(op(par), output = xxx); plots:-display(plots:-odeplot(res1, [[eta, f(eta)], [eta, theta(eta)]]), plots:-odeplot(res2, [[eta, f(eta)], [eta, theta(eta)]])); plots:-display(plots:-odeplot(res1, [[eta, diff(f(eta), eta)], [eta, diff(theta(eta), eta)]]), plots:-odeplot(res2, [[eta, diff(f(eta), eta)], [eta, diff(theta(eta), eta)]])); plots:-display(plots:-odeplot(res1, [[eta, diff(f(eta), eta, eta)]]), plots:-odeplot(res2, [[eta, diff(f(eta), eta, eta)]])); plots:-display(plots:-odeplot(res1, [[eta, diff(f(eta), eta)]])); fplt[j] := plots[odeplot](res1, [eta, diff(diff(f(eta), eta), eta)], color = L[j], axes = boxed); tplt[j] := plots[odeplot](res1, [[eta, theta(eta)]], color = L[j], axes = boxed) end do;
> plots:-display([seq(fplt[j], j = 1 .. nops(n))]);


Dear Sir

In my above problem i trying to plot for set of values of n but in plot command it not executing , can you do this why it is not executing ??

 

ha := (diff(c(t), t))/(c(t)*(diff(c(t), t))-c(t));
solve(subs(m=ha,f(m))*subs(m=subs(c(t)=a(t),ha)), f(m)) = subs(m=ha+subs(c(t)=a(t),ha), f(m), f);

just expect to find a function ?
 

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