How to skip certain return points using the "find" command

I have a random wave form that has an amplitude of 5. I wish to find every point that is over the threshold of 2 and under -2, but only every 5 points. e.g. I found one point over 2, now I cannot detect another point over 2 for another 5 points. I am brand new to matlab and this is just for practice, but any help would be appreciated.

Answer 1

[Oleg Komarov]

% example data

y = sin(0.1:0.1:100)*5;

% Select data over threshold

sel = y(abs(y) > 2);

% Skip every 5 (interval should be 6 because the sixth value is selected)

sel(1:6:end)

Answer 2

[Antti]

If you want also to get indexes (for some reason) with find command:

% example data

y = sin(0.1:0.1:100)*5;

% All indexes over threshold

inds = find(abs(y) > 2);

% Selected point indexes (I didn't get the point of number 6 here)

inds = inds(1:5:end);
sel = y(inds);
plot(sel,'*')

[Oleg Komarov]

The OP says: "now I cannot detect another point over 2 for another 5 points" meaning that the fifth point should be excluded.

1:5:end includes every fifth, but you have to skip that as well.

Btw, I would not call find, it is unnecessary and slows down the routine.