perform a branch and bound optimization

Hi, I need to perform an optimization whose variable is a matrix that has to have only binary values inside (0, 1). To obtain this I tought I could use a branch and bound algorithm, the problem is that I cannot find any optimization function in matlab that can be set with this algorithm. I found this old function on this website,

http://www.mathworks.com/matlabcentral/fileexchange/95-bnb/content//BNB20.m

It would be perfect but once I try to use it it gives me this error

??? Input argument "x0" is undefined.

Error in ==> objfun at 7

It seems that the object function does not "read" the initialized variable x0.

If you could help me performing my optimization with this or any other function I would be extremely grateful (it is for my master thesis)

Thank you in advance

I.

[John D'Errico]

Functions don't "read" variables from your workspace. You need to pass them in. Think about how you use ANY function in MATLAB. Do those functions just magically know how you want to use them, and what you intend to pass in? For example, consider the function mean. You pass in an argument. All functions are the same in this respect.