Starting with an array of x-y-z data, I need to find an array of unique values of x-y and as the z value the max z for the same (x,y) combination.

Hi,

I have x,y, z scatter data. I need to find for the same x and y coordinates the maximum z value. so for example:

x y z

1 2 10

2 2 5

2 1 8

2 2 7

I get:

x y z

1 2 10

2 1 8

2 2 7

Order of data is not important. Values in general are not integers.

Thanks for the help, I've tried differents methods with no success.

Answer 1

[Ameer Hamza]

Try this

M = [
    1    2    10
    2    2    5 
    2    1    8
    2    2    7];

[u_rows, ~, idx] = unique(M(:,[1 2]), 'rows');
max_vals = splitapply(@max, M(:,3), idx);
M_out = [u_rows, max_vals]

Result

>> M_out
M_out =
     1     2    10
     2     1     8
     2     2     7

[Fabrizio Argentieri]

Great! thank you for the quick answer, this worked well, except i had to reduce precision of x,y data otherwhise it missed some nearly identical values.