Mean and standard deviation of a field - condition on another field
조회 수: 11(최근 30일)
Hi. I am working with a structure array S (1 X 50,000) with 10 fields. I want to calculate the mean and standard deviation of field f1 based on a condition on field f2.
Here is the input,
S(1).f1=[10,20,30 40,50,60] and S(1).f2=[100,20,50,60,70,140];
S(2).f1=[56,98,74,87,99] and S(2).f2=[101,54,69,20,11]
S(3).f1=...... and S(3).f2=.....
S(4).f1=.... and S(4).f2=.....
S(i).f1=.... and S(i).f2=....
I want to calculate the mean of f1 elements whose corresponding f2 field values are 50 < f2 <=100
Meaning, S(1).f1=[10,40,50] and S(2).f1=[98,74] should be considered in calculation of mean.
I want to calculate several mean values of f1 based on different conditions on f2.
the cyclist 2019년 8월 30일
편집: the cyclist 2019년 8월 30일
The mean and standard deviation of f1, for the elements where 50 < f2 <= 100, can be calculated as follows:
arrayfun(@(x)mean(x.f1(x.f2>50 & x.f2<=100)),S);
arrayfun(@(x) std(x.f1(x.f2>50 & x.f2<=100)),S);
arrayfun will apply a function to each element of a structure array, so it is a vectorized way of doing the operation.