MATLAB: Error when using min function

MATLABmatrix

I have a 180×180 matrix of random integers and I am simply trying to find the smallest element but everytime I run the code it says "Index exceeds matrix dimensions." and refers to my last line of code. Any suggestions?
N1 = randi([1,500],45,45);
N2 = randi([25,1000],45,45);
N3 = randi([100,2200],45,45);
N4 = randi([5,700],45,45);
N5 = randi([100,500],45,45);
N6 = randi([800,3500],45,45);
N7 = randi([1000,10000],45,45);
N8 = randi([15,1000],45,45);
N9 = randi([250,900],45,45);
N10 = randi([5000,11000],45,45);
N11 = randi([1750,9000],45,45);
N12 = randi([25,890],45,45);
N13 = randi([2000,7500],45,45);
N14 = randi([200,2300],45,45);
N15 = randi([25,750],45,45);
N16 = randi([50,1323],45,45);
N = [N1 N2 N3 N4;
N5 N6 N7 N8;
N9 N10 N11 N12;
N13 N14 N15 N16];
M = min(N(:))

Best Answer

Hi Andrew, this is a hypothetical answer but it may be that you have, somewhere else, defined 'min' to be a variable .e.g min = 4 or similar.