length() gives the max length of the longest dimension of an array. So you can either use
A=[1,2,3;4,5,6]
maxval = -inf;
for k = 1 : numel(A)
if A(k) > maxval
maxval=A(k)
end
end
or use two indexes and two loops:
A=[1,2,3;4,5,6]
maxval = -inf;
for row = 1 : size(A, 1)
for column = 1 : size(A, 2)
if A(row, column) > maxval
maxval=A(row, column)
end
end
end
