I've got a large matrix, mainly consisting of zeros and with some randomly placed values. I would like to be able to find the surrounding zeros of the non-zero values. If a single value is only surrounded by zeros it's no problem, but a cluster of values poses more problems. I could treat the values in the cluster as single values, but that means an extremely long runtime of the code. Is there a way to find all zeros surrounding a certain value? I don't have any additional toolboxes, but if there is one that could be usefull, I can always try to convince my boss that I need it...
