Selecting certain rows in an array

Hi all, Matlab newbie here. I'm sure this is not a complicated question but I'm having no luck.

I have an array of 512 rows and 5 columns. Let's say column 1 is called A, 2 is called B, etc. I want to find row numbers where the value in A>0.10*max(A) and B<0.10*max(B), C<0.10*max(C), D<0.10*max(D). In other words, I want indexes where the value in only one column is greater than 10% of the max value in that column.

Any ideas? Thank you in advance, I learn a lot from these answers.

Answer 1

[Walter Roberson]

Supposing the array is R, then

cutoff = 0.10 * max(R);   %max goes column by colum

find( R(:,1) > cutoff(1) & R(:,2) < cutoff(2) & R(:,3) < cutoff(3) & R(:,4) < cutoff(4) )

[Molly]

Worked like a charm! Thank you :)