This function is based on UTM.m function by Gabriel Ruiz Martinez, but instead of providing a GUI it works with vectors of coordinates.
[x,y,utmzone] = deg2utm(Lat,Lon)
% Example 1:
% Lat=[40.3154333; 46.283900; 37.577833; 28.645650; 38.855550; 25.061783];
% Lon=[-3.4857166; 7.8012333; -119.95525; -17.759533; -94.7990166; 121.640266];
% [x,y,utmzone] = deg2utm(Lat,Lon);
% fprintf('%7.0f ',x)
% 458731 407653 239027 230253 343898 362850
% fprintf('%7.0f ',y)
% 4462881 5126290 4163083 3171843 4302285 2772478
% utmzone =
% 30 T
% 32 T
% 11 S
% 28 R
% 15 S
% 51 R
%
% Example 2: If you have Lat/Lon coordinates in Degrees, Minutes and Seconds
% LatDMS=[40 18 55.56; 46 17 2.04];
% LonDMS=[-3 29 8.58; 7 48 4.44];
% Lat=dms2deg(mat2dms(LatDMS)); %convert into degrees
% Lon=dms2deg(mat2dms(LonDMS)); %convert into degrees
% [x,y,utmzone] = deg2utm(Lat,Lon)
%