Find Min of Matrix without using MIN or explicit loops (FOR or WHILE)

I am reviewing for a test and my teacher loves to ask us questions that require the removal of explicit loops (FOR and WHILE) and use implicit (Array Operations) instead. For example instead of 

for n=1:100
     b=sin(n);
end
b

instead use

n=1:100;
b=sin(n);
b

so the function we are to convert is as follows A is an arbitrary predifined Matrix

clear,clc
for m=1:length(A(1,:));
    S(m)=A(1,m);
    for k=2:length(A(:,1));
         if(S(m)>A(k,m))
                S(m)=A(k,m);
         end
     end
end
S

Where S is a vector with the minimum value of each column. I know this could be solved with Min(A), but that is not what is being ask. How would I use vectorization to make the same above operation to work?

Answer 1

[John D'Errico]

Well, perhaps you might look at the tools matlab provides. What directory does the function min reside in? (which will help you here.)

Look at the other tools in that same directory. Would any of them be capable of helping you?

[Stephen Smitherman]

How would knowing the directory help. I cant seem to view the source code of min.m.

[John D'Errico]

I was not telling you to read the source code for min, something I know that you cannot do. However, had you looked in that directory, you would have found various functions. Reading about them would quickly have taught you about a few of the tools available in matlab. One of those functions is sort, a tool which does allow you to solve the problem, as others have by now shown. Your teacher is trying to teach you to think outside of your normal patterns. Follow that lead.

Answer 2

[Matt Fig]

Here is a way to do it without MATLAB loops. Though I think the idea John has in mind would be better!

mn = sort(A);
mn = mn(1,:);

[Stephen Smitherman]

OMG I cant believe that works. I can't seem to get my head to think to use other functions like that. Thanks. I now see what John meant.

[Stephen Smitherman]

Although can you possible think of a way to do this without calling another function and replicate with vectors what the for loops do above?

[Matt Fig]

Let me see. No loops and no function calls? You could hand write a bunch of consecutive IF statements, thereby limiting the size allowed for the input. Other than that I don't see how it could be done without either loops or some function call.