How to calculate mean value of a parameter within interval of other parameters

Hi,

The title is perhaps not very clear...

I have a 3 vectors X, Y and Z of same dimension N.

I have also 2 intervals vectors containing the limit of each interval (wich are not necessary equidistant) of X and Y values: int_X (dimension i_X) and int_Y (dimension i_Y).

I want to calculate the mean value of Z for each interval of both int_X and int_Y (each "square" of the (int_X,int_Y) plane), and put the results in a matrix of dimension (i_X,i_Y).

Of course, I can do it with 2 "for" loops, but I would like to find a more elegant method without for loops.

Answer 1

[millercommamatt]

Assuming I've understood your description of your arrays correctly... i.e. that int_X and int_Y contain max and min values for the X and Y bounds respectively. e.g. X_int = [x_min, x_max];

Z_bounded = Z(X>int_X(1) & X<int_X(2) & Y>int_Y(1) & Y<int_Y(2));
mean(Z_bounded(:));

If there are multiple intervals defined, you could put the above in a for loop.

[Laurent Fregosi]

Thanks Matthew.

But in fact, int_X contains sevral boundaries. For example, int_X = [0 1 2 5 10] and int_Y=[0 10 50 100].

I try to have the mean of Z for all the combination of each intervals of int_X and int_Y (for example one mean value will be when X is between 1 and 2 and Y is between 50 and 100, etc... for each combination

Hpe it's clear...