Loop to check if 2 conditions are true for values 1:n, (1:n)+1, (1:n)+2, etc. in a vector and save ID

Hi everyone,

I have a time series of daily precipitation (i.e. a vector of 365x1) and I would like to test 2 conditions :

• is the cumulative rainfall over 7 days > threshold (e.g. 10mm)
• are there at least 4 out of 7 days with precipitation (RF > 0mm)

I want to make a loop to take values 1:7, check whether the 2 conditions above are met, go to 2:8, 3:9, etc., until the first occurrence of a 7-days period for which both conditions are met. Then save the ID of the last day of the 7-days period (e.g. if the conditions are met first for 43:49, save the ID of interest is 49, I don't care about the value in the vector, only the ID).

I have no idea how to even start or what function to use, so any help is welcome.

Thanks !

[KALYAN ACHARJYA]

Start with example data, just for two weeks (generate random data), it can be possible.

Answer 1

[Torsten]

for i=1:365-7+1
    period = rainfall(i:i+6);
    sum_period = sum(period);
    n = numel(find(period>0));
    if sum_period > threshold && n >= 4
        ID = i+6;
        break
    end
end

[Loriann Chevalier]

This is exactly what I was hoping for. Thank you very much!