Hi, 

I want to animate this code 

plots[odeplot](Trajectoire, [[x1(t), y1(t), t], [x2(t), y2(t), t], [x3(t), y3(t), t], [x4(t), y4(t), t], [x5(t), y5(t), t], [x6(t), y6(t), t], [x7(t), y7(t),t], [x8(t), y8(t), t], [x9(t), y9(t), t], [xA(t), yA(t), t]], TempsInitial..TempsFinal, numpoints = 10000,axes=boxed, scaling = constrained);

However, Maple 16 is giving me an error message :

Error, (in plots/animate) the first argument must be a procedure

I don't know how I can do to animate this code.

Thanks!

Hi

worksheet output doesnt display the eigenvalues of a 19X19 matrix. Just gives in the form Root of(...). when datatype is indicated as anything other than complex(sflot) it gives error "unable to store". solution is required in compact mathematical expression form (may involve square roots etc). Please help.

Thanks

I am looking for a spreadsheet to compute the precession of Mercury fom the Schwarzchilg metric and the geodesic equations. Are you aware of such an example?

When I try "touch and drag" in Maple documents, the documentation for example, I end up selecting text instead of scrolling. Unfortunately the alternatives for scrolling are a) the scrollbar, b) page-up/down or c) moving the cursor. Each of those alternatives is about 2.5311 orders of magnitude more inconvenient than touch&drag.

Does anybody know if its possible to get Maple (18) to scroll instead of select text when I touch the screen?

Hello,

I am using Maple 17 to solve some equations. I am solving these equations with the solve command. There are some bounds on the parameters so I am including these inequalities. I have 4 variables, so I solve for 3 to get them in terms of the last one.

It returns piecewise solutions as per the inequalties as I hoped.

However for two ranges of the inequalities I get [] which I assume means no solution.

For another range I get an expression for each of my paramters.

For the final range I get 0 . What does this 0 mean and what do the [] mean?

I wondered if 0 meant that all paremeters equalling zero was a solution, but this is false.

Thanks

Hi there

There seems to be a bug when evaluating elliptic integrals using assuming. Here's an example:

INT:=Int(1/sqrt(a*x^3+1),x=0..X);

is our integral for some a. Now evaluate the integral using assuming on X in different ways:

INT2:=simplify(value(INT)) assuming X>0, a>0, a<1;

INT3:=simplify(value(INT)) assuming X<0, a>0, a<1;

These give analytic solutions which are different. Now plot them both and compare to the numeric solution

plot([subs(a=0.1,INT2),subs(a=0.1,INT3),subs(a=0.1,INT)],X=-1..1,colour=[red,green,blue]);

I'm finding that the red curve which should work for X>0 is wrong, while the green one which is for X<0 is ok for X either sign. [blue is the correct answer - numerically!]

Any ideas?

Good afternoon sir.

Please let me know how to upgrade mu current version Maple17 to Maple 18.

With thanks & Regards

M.Anand

Assistant Professor in Mathematics

SR International Institute of Technology,

Hyderabad, Andhra Pradesh, INDIA.

Good afternoon sir.

I request your kind support to the above cited query.

With thanks & Regards

M.Anand

Assistant Professor in Mathematics

SR International Institute of Technology,

Hyderabad, Andhra Pradesh, INDIA.

Good afternoon sir.

I request your kind suggestion to the above cited query.

With thanks & Regards

M.Anand

Assistant Professor in Mathematics

SR International Institute of Technology,

Hyderabad, Andhra Pradesh, INDIA.

Dear all,

I need your help.

I compute the exact solution u(x,y,t) os PDE.
My code : PDEs.mw

I would like to plot the exact solution of my PDE.

My method work well but  when I put a:=1; b:=1; In the next lines there is no change, always I have a and b in my equation.

If i fix the time, "t=1 or 2 " for example; In the last lines i plot( u(x,y,2)); but doesn't work also.

Then animation in "t" how....

Thanks for your help.

Dear All

Please help me for using fsolve

the fsolve command doesnt work!

> restart;
> with(LinearAlgebra); Digits := 20;
print(`output redirected...`); # input placeholder
> Z := Matrix(2); N := 3; y11 := sum(a[n]*x^n, n = 0 .. N); y12 := sum(b[n]*x^n, n = 0 .. N); y21 := sum(c[n]*x^n, n = 0 .. N); y22 := sum(d[n]*x^n, n = 0 .. N); y11 := unapply(y11, x); y12 := unapply(y12, x); y21 := unapply(y21, x); y22 := unapply(y22, x);
print(`output redirected...`); # input placeholder
> A := linalg[matrix](2, 2, [1, -1, 1, exp(x)]); B := linalg[matrix](2, 2, [-3*exp(-x)-1, 2-2*exp(-x), -3*exp(-x)-2, 1-2*cosh(x)]);
print(`output redirected...`); # input placeholder
> C := eval(B, [x = 1]);
print(`output redirected...`); # input placeholder
> Y := linalg[matrix](2, 2, [y11(x), y12(x), y21(x), y22(x)]);
print(`output redirected...`); # input placeholder
> yy11 := diff(y11(x), x); yy12 := diff(y12(x), x); yy21 := diff(y21(x), x); yy22 := diff(y22(x), x); yy11 := unapply(yy11, x); yy12 := unapply(yy12, x); yy21 := unapply(yy21, x); yy22 := unapply(yy22, x);
> YY := linalg[matrix](2, 2, [yy11(x), yy12(x), yy21(x), yy22(x)]);
print(`output redirected...`); # input placeholder
> S := {seq(eval(YY, [x = n/N])-(eval(A, [x = n/N]))*(eval(Y, [x = n/N]))-(eval(B, [x = n/N])) = Matrix(2), n = 1 .. N)};
print(`output redirected...`); # input placeholder
> S1 := {eval(Y, [x = 0]) = linalg[matrix](2, 2, [3, 0, 1, 1])};
print(??); # input placeholder
> SS := `union`(S, S1);
print(??); # input placeholder
> sol := fsolve(SS);

firstly apologies in advance for stuff in this question such as "triangle symbol",  my computer is pretty old. 

ok so i was confused a bit here, what i'm trying to do is write a maple procedure that computes Af for a given f contained in V . except we only need to correct the bug in the script below. This script demonstrates such a procedure in the case that omega is a square. The domain is given here as the negative set of a function F contained in V .  I have left in notes where/what i think we need to do but i dunno how to...

N:=10 ; # Global Var
F:=(x,y)->sgn(abs(x-N/2)+abs(y-N/2)-N/4);
Average := proc(F, f0) local f, i, j;
f := f0; # !!!!!!!!!!!!!! something is bad here...
for i to N do for j to N do
if F(i, j) < 0 then
f[i, j] := (f0[i - 1, j] + f0[i + 1, j] + f0[i, j + 1] + f0[i, j - 1])/4 ;
end if;
end do;end do;
return f;
end proc;
f0:=Matrix(N,F); # just to have something to test the procedure
Average(F,f0); # does not return the expected average, modifies f0

the necessary information we were given to produce this so far was..

Let N be a positive integer and [N] = {i contained in N | 1<= i <=N }  Let "Omega" C {(i,j) contained in [N] x [N] | 2<=i,j<=N-1} be a subset. Let V = R^([N]x[N]) be the vector space of real valued functions [N]x[N] -> R
and A,
"triangle symbol":V->V (average) and "triangle symbole" (Laplacian) be the linear maps such that
[Af](i; j) = f(i; j)      if (i; j) not contained in "Omega"   OR

                             [f(i, j + 1) + f(i, j - 1) + f(i + 1, j) + f(i - 1, j)]/4 if (i,j) is contained in "Omega"

["traingle symbol"f](i,j) =  0 if (i,j) isnt contained in "Omega"   OR

                            ( f(i,j) - [f(i, j + 1) + f(i, j - 1) + f(i + 1, j) + f(i - 1, j)]/4 )    if (i,j) is contained in "Omega"

 Please and thank you for any help in advance <3

Hello,

Maple needs 827 characters to write a equation of a straight line.
Is that true or what am I doing wrong?   

Can anybody help me or give a direction to handle with such problems?

Putting
  assume(2<alpha , alpha<=4);about (alpha);
before it does not help either.

f:=-(6*(3*alpha^2*(alpha-1+sqrt(alpha^2-3*alpha+2))^4/(alpha-1)^4-12*alpha^2*(alpha-1+sqrt(alpha^2-3*alpha+2))^3/(alpha-1)^3-6*alpha*(alpha-1+sqrt(alpha^2-3*alpha+2))^4/(alpha-1)^4+16*alpha^2*(alpha-1+sqrt(alpha^2-3*alpha+2))^2/(alpha-1)^2+24*alpha*(alpha-1+sqrt(alpha^2-3*alpha+2))^3/(alpha-1)^3+3*(alpha-1+sqrt(alpha^2-3*alpha+2))^4/(alpha-1)^4-8*alpha^2*(alpha-1+sqrt(alpha^2-3*alpha+2))/(alpha-1)-24*alpha*(alpha-1+sqrt(alpha^2-3*alpha+2))^2/(alpha-1)^2-12*(alpha-1+sqrt(alpha^2-3*alpha+2))^3/(alpha-1)^3+8*(alpha-1+sqrt(alpha^2-3*alpha+2))^2/(alpha-1)^2+8*alpha+(8*(alpha-1+sqrt(alpha^2-3*alpha+2)))/(alpha-1)-7))/(alpha*(alpha-1+sqrt(alpha^2-3*alpha+2))^2/(alpha-1)^2-2*alpha*(alpha-1+sqrt(alpha^2-3*alpha+2))/(alpha-1)-(alpha-1+sqrt(alpha^2-3*alpha+2))^2/(alpha-1)^2+(2*(alpha-1+sqrt(alpha^2-3*alpha+2)))/(alpha-1)-1)^4;

Hello,

• Is there a simple way to find the domain for the real solutions of f(x)?

• And is there a way to let maple get the part of f(x) with the sqrt?
   (not by typing it by hand as I dit below)

• Is there a way to write the summary of the found domains in one line?

Thanks for your help. 





restart:
# How to find the Domain for real solutions for x?
f(x):=(x-1+sqrt(x^2-3*x+2))/(x-1);
discont_for_x=discont(f(x),x);
# x<>+1 (because the de denom=0 is not allowed)
denom(f(x))=0;
x={solve(denom(f(x))=0,x)};
# x<=1 union  2<=x (because the part under the sqrt must be >=0 to give Real solutions)
sqrt(x^2-3*x+2);
0<=x^2-3*x+2;
x=solve(0<=x^2-3*x+2,x);