Hello everyone,

I have an ODE for which I want to show that any initial condition leads to a convergence towards a point. So far I made a sequence of dsolve procedure, each with a distinct random initial condition, and I can plot everything on the same plot without a problem with display.

The parameter of the ode is the time t, so that the system of ode is some d/dt x(t) = f(x(t),y(t),z(t)), etc. To show time passing, I have two solutions in a sense, either by color, or by an animation. But the latter is not very convenient as I am already planning of to animate the rotation of the camera since the plot is 3D. What I would like, is the color of the curve to be say blue at time 0 then go to green as t goes to 5, for example.

I know something should be possible as there is somehow an example given in plot3d documentation,
plot3d(x*exp(−x^2−y^2),x=−2..2,y=−2..2,color=x)
but I can't seem to make it work, no matter where I put my "color = t" option. Would one have an idea on how to achieve that?

Thank you for your time,
Cryme

Hello,

I am experiencing some trouble with the function Minimize of the Optimization package. I have some trouble understanding what Maple is doing with nice functions already.

f := (x-2)^2+1;
                                 2    
                          (x - 2)  + 1
Minimize(f, {x >= -2, x <= 2});
             [1., [x = HFloat(1.9999999999999998)]]
Minimize(f(x), {x >= -2, x <= 2});
                    [1., [x = HFloat(2.0)]]
g := proc (x) options operator, arrow; (x-2)^2+1 end proc;
            2    
x -> (x - 2)  + 1
Minimize(g, {x >= -2, x <= 2});
Error, (in Optimization:-NLPSolve) constraints must be specified as a set or list of  procedures
Minimize(g(x), {x >= -2, x <= 2});
             [1., [x = HFloat(1.9999999999999998)]]

Hello,

I am facing a problem, I have a system of nonlinear inequalities that has solutions for the sake of the example:
xy-1<0, x>0, y >= 1
Here we can just say that for any 1>x>0, the y for which it is satisfied are 1/x > y >=1, and in that sense it gives a depiction of the set of all (x,y) that satisfies the system. But I would rather like to know one particular solution say x=1/2, y=1 for example. Is there a way to generate a particular solution of such a system without having to write a procedure that tests all x,y with three digits after the comma within a given range?

Thank you