How to create a cumulative frequency array

I am trying to create an array to compute the cumulative frequency of array Z, which are less than or equal to the time in minutes specified by the minutes array, V.
X1= sqrt(rand(1,1000));
X2= normrnd(20,5, 1,1000);
w= rand(1,1000);
X3 = (-log(1- w));
sz = [1 1000];
X4 = unifrnd(4,15, sz);
Z=X1+X2+X3+X4; %(note: Z is an array with 1000 values in one row)
V = linspace(1, 1000, 1000); %array V

 Accepted Answer

This is inelegant, but it works:
cumFreq = zeros(size(V));
for i=1:numel(V)
cumFreq(i) = sum(Z<V(i));
end

5 Comments

so this computes the frequency per location in array??
Thanks!! i will try it out
This does not seem to give me cumulative frequency per trials. like if there was 3 values in Y array that are less than V array then when it finds 3rd that fits logic it will give me 3 in new array. Freq+1+1+1 because logic has be fulfilled 3 times.
hope im explaining it well
No, sorry, I guess I misunderstood the problem. Maybe a small numerical illustration would help make it clear what you are trying to count?
so this is what i ended up with after many attempts
im trying to get frequency at each time step (V) for Z
V = linspace(1,1000,1000);
j = 1;
while sum(Y > V(j))>0
for j=j+1
freq(j) = sum(Z <= V(j));
end
end
thanks to your guidance. it was working just needed a tweak

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Asked:

on 28 Apr 2021

Commented:

on 30 Apr 2021

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