help: creating vectors.

I have to create a vector, which returns 4 for the first 30 numbers, 5 for the next 31, the next 6 to 30 etc. etc. in particular, it must give me a number from 4 to 14, repeated for a number of times equal to 30, 31 or 28, in the order (30, 31, 30, 31, 31, 30, 31, 30, 31, 31, 28), or 30 4 times, 31 5 times, 30 6 times, etc. etc

Answer 1

[KSSV]

If you want 31 5 times, 30 six times use like below:

[31*ones(1,5) 30*ones(1,6)]

You can add whatever you want in the above code similarly.

Answer 2

[Jan]

This is a job for repelem:

Rep   = [30, 31, 30, 31, 31, 30, 31, 30, 31, 31, 28];
Value = 4:(3+length(Rep));  % Test data
R     = repelem(Value, Rep);

This was introduced in R2015a. If you have an older version, you can either use FEX: RunLength:

RunLength(Value, Rep)

Or program it explicitly:

len   = length(Rep);        % Number of bins
d     = cumsum(Rep);        % Cummulated run lengths
index = zeros(1, d(len));   % Pre-allocate
index(d(1:len-1)+1) = 1;    % Get the indices where the value changes
index(1)            = 1;    % First element is treated as "changed" also
R     = Value(cumsum(index));

[Pasqualina Verolino]

wow it fix perfect! thank u so much!