Would you please post an example of this?

@Gaia 1. When you get that message "Length of output exceeds 0 ...", the computation is still performed; it is just not displayed on screen. It is possible to increase this limit, but do your really want to see such a large output?

2. Maple is used in distributed processing. The Grid package facilitates this. See ?Grid .

@Gaia Sorry, I was wrong: nextperm, etc., will not work with restricted size permutations. There are two other permutation iterators that will work.

Method 1: package combstruct

with(combstruct):
list6:= convert(list5, list):
Iter:= iterstructs(Permutation(list6), size=2):
while not Iter[finished] do
     p:= Iter[nextvalue]()
end do:

Method 2: package Iterator

You'll need to download Iterator from the Maple Applications Center. And I think that it requires Maple 17. It definitely requires Maple 16 or greater.

for p in Iterator:-Permute(list6, 2, compile= false) do
     print(p)
end do;

@bails123 For the plot, you make a simple change to relabel the horizontal axis as z/b, with the range being 0..1:

plot([seq(BesselJ(0, BesselJZeros(0,n)*sqrt(`z/b`)), n= 1..4)], `z/b`= 0..1);

You wrote: For the animation, since I cannot obtain values for K[n], I was thinking I could plot y_n(z,t)/K[n] as a function of t.

Hmm. I don't see how that's different from setting K[n] = 1, which is what I did.

You wrote: Sorry, I should have been more clear, it was an animation as a function of t.

So, you want the horizontal axis to be t and the animation variable z?

@stevens1111 You are missing a multiplication sign in your definition of P(z).

@mbacon29 Your fourth initial conditions have x*0 where it should be x(0).

Do you want to find the maximum value of u? Over what range of a? The same as in the graph?

What is N (you have N= 0.5..1)?

Was there a particular command that rejected your pdesys in the form that you have it above?

I was able to take your code, with no changes whatsoever, and get the same plot as Markiyan. Extra spaces between words should not matter.

I recommend that you place the restart in a separate execution group and try again. A restart should always be in its own execution group.

@Kitonum This can be improved by not requiring a priori knowledge of the range of exponents:

add(coeff(P(z),z,n)*z^(``(n)), n= ldegree(P(z),z)..degree(P(z),z));

@Joe Riel That's great, Joe. You should put that on the Applications Center.

So, it is possible to read from the mouse in Maple.

This is an integral equation of a type that Maple does not know how to solve. So, you'll need to transform the equation somehow.

How many points are there for which f(x)=0? Do you mean that D(f)(a) = -K where a is the first value to the right of 0 such that f(a)=0 and that you want the boundaries for the BVP to be 0 and a?

@dungct What do you want it to return other than zero?

@sarunas 

evalf(arctan(519/520));
                       0.784435699787033
evalf(convert(%, degrees));
                    44.9448548971883 degrees