How can I rearrange a vector?

I have a vector

a = [9 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 9];

How can I rearrage it to

a = [0 0 0 0 0 4 3 2 1 0 1 2 3 4 0 0 0 0 0];

Thank you!

Answer 1

[Jan]

Some bold guesses of what you want to achieve:

aa = [9 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 9];

a = aa;
a(a >= 5) = 0

a = aa;
a(~ismember(a, 1:4)) = 0

a = aa;
a(ismember(a, 5:9)) = 0

a = aa;
a([1:5, end-4:end]) = 0

a = aa;
n = numel(a);
a(abs((1:n) - (n + 1)/2) >= 5) = 0

There is an infinite number of methods to produce the wanted output based on the given input. The current explanations are not enough to find the general solution.

[Jeah MK]

Thank you! The first one works pretty well!