How to check an array for max and min values

function [shallow,deep] = marinaraTrench(arrayz)
min=realmax;
max=0;
for i=1:size(arrayz)
    if arrayz(i)>max
        max=arrayz(i)
    end
    if arrayz(i)<min
        min=arrayz(i)
    end
end
shallow=min
deep=max
end

I'm trying to find the max and minimum values of an array using for loops alone and for some reason it's not always returning the right values

[Walter Roberson]

You should be initializing

max = -realmax;

[Alexander West]

what does this do?

[Walter Roberson]

Your code would fail if the maximum value was < 0 because you were initializing the bound on the maximum to 0.

Answer 1

[Walter Roberson]

You should be looping to numel() of the array, not to size() of the array. size() returns a vector of values, so your for loop becomes for i=1:VECTOR . MATLAB defines that as being the same as for i=1:VECTOR(1) which would be for i=1:size(arrayz,1) .

Note: using variables named max and min is going to confuse readers. At if you get into the habit of using those as variable names, you can be 99% sure that at some point, you are going to confuse yourself heavily in some program where you use them as variable names but then expect the functions with those names to work properly.

[Alexander West]

oh, okay thanks! i couldn't understand why size/length wouldn't work, but thank you, I get it now!