Hello everyone. I'm a french student and I make a study on the double pendulum. I have written all of the equations into maple (6 equation for solid movement and 2 for point movement). We will work with 2 equations.

So i got my 2 differential equations (non linear) and I want to odeplot them and after plot the 2 solutions with plot.

Unfortunatly, after reading some post here and solutions, my problem still exist. When I odeplot my solutions : i have a warning message (so also when I plot) :

How do I rewrite a expression in terms of other expressions? (Using just algebraic transformations.)

I'm look for something like algsubs. algsubs does not work for some non-trivial cases: I get the error "cannot compute degree of pattern in...". Playing a bit with these expresions (replacing denominators, and some subexpressions), I can transform in various steps, applying algsubs, to get the desire result, but I don't know how do this automatically.

I am trying to solve the following bvp:

with*plots

Eq[1] := diff(f(eta), `$`(eta, 3))+3*f(eta)*(diff(f(eta), `$`(eta, 2)))-2*(diff(f(eta), eta))^2+theta(eta)

Eq[2] := diff(theta(eta), `$`(eta, 2))+3*Pr*f(eta)*(diff(theta(eta), eta))

Eq[3] := diff(phi(eta), `$`(eta, 2))+3*Sc*f(eta)*(diff(phi(eta), eta))-kappa*Sc*(phi(eta)*(diff(theta(eta), `$`(eta, 2)))+(diff(theta(eta), eta))*(diff(phi(eta), eta)))

BCs := [f(0), (D(f))(0), ((D@@2)(f)...

Hello everyone !

First of all, excuse my English if it's difficult to read, I'm french.

I'd like to draw a surface/shape in 3D in spherical and I used plot3d with coords=spherical to do so. But I'd like to color on the picture to change when R(theta,phi) changes. I could visualize how R is changing and where it is the same. But I have no idea how to do so...

I can't put the picture here, the formula is too long...

good say !

I want for my work to calculate the International Equation of State of Seawater

but when i enter my fonction in mapple: it is like mapple don't recognise the second variable s:

>t:= -> t;
s:= -> s;

> g :=(t, s)-> 999,842594+6,793952*10^(-2)*t-9, 95290*10^(-3)*t^2+1, 1685*10^(-4)*t^3-1, 120083*10^(-6...

Hi,

I would like to extract data from 3d implicit plot. I try this:

> points := plots[implicitplot3d]((x^2*(1-x^2)-y^2)^2+0.5*z^2-0.025*(1+1.0*(x^2+y^2+z^2)) = 0, x = -1.5 .. 1.5, y = -1.0 .. 1.0, z = -1.0 .. 1.0, numpoints = 1000);

> ptslist := convert(op([1, 1], points), listlist);

> ptslist[1..12];

Maple prints a list:

[[[-1.50000000000000, -1., -1., 14.9039062500000], [-1.50000000000000, -1., -.818181818181818, 14.7468814566116...

I was able to try the code on M15 and M16 but the final answers are slightly different.  Why is that?  Shouldn't they all come up with the same value?

The value for M15 came up with the same as value as M12 but M16 was different.

Using p(.22,80*3600)

M12  [x = .22, t = 288000., T = 685.116351910514254]

M15  [x = .22, t = 288000., T = 685.116351910514254]

M16  [x = .22, t = 288000., T = 685.11635191051

Hi

How can I resize inline plot-window without mouse? (I know about resize tool, but it displays plot in new window :( )

And how can I display 5 plots in one line one by one?

Thx :)

I cannot make Maple find the solution for the integral of sqrt(x/(1+b*x^3)) assuming x>0 and b>0, which is 2*arcsinh(sqrt(b*x^3))/(3*sqrt(b)). Mathematica does this without any problems. What am I doing wrong?

How do I stop maple from running the rest of the worksheet in case an error occurs in the middle of it? Which command should I use?

More specifically, I have a program in which I input the masses of the particles and then the program will calculate the corresponding parameters of the potential, and will do a lot of other stuff with these parameters. However, it these parameters happen to be complex, the program should simply halt with a warning: "your parameters are complex, cannot continue".

Good day! Some of my tasks are quite time consuming. What maple command I have to use in order to get some sound signal when calculation is over?

See http://mathematica.stackexchange.com/ and compare with MaplePrimes.

Hi

I've got a list of inequalities

[x > 5, 10 < x]

and I need to plot the region by

plots[inequal]( [x > 5, 10 < x], x = 4 .. 11, y = 0 .. 1);

but I don't want to specify x-range.

So how can I get the numbers from inequalities and generate something like "x = 5-1 .. 10+1"?

Thx :)

I realize that Maple itself does everything but I would like a simpler cheaper solution for a number of computers in my classroom.  Multiple licenses of Maple is not an option. 

I realize that Maple itself does everything but I would like a simpler cheaper solution for a number of computers in my classroom.  Multiple licenses of Maple is not an option.