@Mariusz Iwaniuk 

Okay, change +a to -a and change the assumption to a < 0. Then it works.

@vv Sorry about that. That's why my final animation seemed slower. The moral of the story is that I should use restart before testing!

@Markiyan Hirnyk I did comment on the purpose of parameter mu in my code below.

@Markiyan Hirnyk The parameter mu is the number of iterations between frames. In other words, every point makes mu micro-movements between frames.

@vv Try reducing the number of frames (the second parameter) from 600.

Did you change the number of starlings (points)? That hasn't worked well for me either. At 3000, they all get stuck.

@vv Do you mean that the code doesn't work in Maple or that when viewing the above animation in MaplePrimes all the frames are the same?

@acer See below for the adjusted appliable module that I posted a few minutes before your last Reply.

@mriedel Indeed it is easy to verify that the algebraic form is a pole. The command to do it is evala(Normal(...)):

evala(Normal(eval(z^4 + 2*z^2 + 2, z= rr)));

     0

I've never encountered an algebraic-number expression which was equal to 0 which evala(Normal(...)) wasn't able to prove was equal to 0, although sometimes it has taken a few minutes.

Unfortunately, the simplistic code showstat(residue) doesn't call evala(Normal(...)).

@mriedel It's not really another issue. It is the issue. The command residue works by simply calling series. Check out the simplistic code with showstat(residue).

@Markiyan Hirnyk It isn't possible for Maple to produce an animation without a fixed number of frames and hence cycling. So don't blame vv's code for this defect.

@mriedel Maple has no trouble converting r to algebraic form. What it has trouble with is simplifying that algebraic form to something which is recognized as a pole of the expression.

rr:= convert(r, radical);

     rr := 2^(1/4)*((1/2)*sqrt(2-sqrt(2))+(1/2*I)*sqrt(2+sqrt(2)))

evalf(residue(z^2/(z^4 + 2*z^2 + 2)^2, z= rr));

     Float(infinity)-Float(infinity)*I

I see in the MSE link that you have given a simplication r1 => r. I don't see a simplification r => r1, which is what is needed for residue to work.

@vv Vote up.

But I think that it'll be much smoother and much more like the original with much less reconfiguring of E and F. I completely removed the the line

if rand(1..10)()=1 then FE() fi;

and I got a fine animation for the 200 frames. So, I'd make the 10 much larger. I'd also set the maximum number of entries of E and F that can change on any iteration at about 1/3.

An alternative would be to change a very small fraction of E and F on every iteration. I'm implementing this idea right now.

@mskalsi Most of my worksheets are short, so I don't need to use the feature much. However, I have my global setting such that it always asks me to select a server, just in case.

@Markiyan Hirnyk Ah, I didn't know that, Vote up, because now Explore seems betters than an animation.

What do you want to know about cmaple? It's on-board help page is very thorough.