function [time,mint,maxt] = mat2posix(time)


time(find(time==0)) = NaN;
for i=1:size(time,1)
    for j=1:size(time,2)
         if ~isnan(time(i,j))
            time(i,j) = posixtime(datetime(datestr(time(i,j))));
         end
    end
end

mint = min(min(time));
maxt = max(max(time));