a=[1 2 3
4 5 6
7 8 9
10 11 12
13 14 15
16 17 18];
fid = fopen('data1.txt', 'w');
for i=1:size(a)/2
fprintf(fid,'0%d00\n',i);
fprintf(fid, '%d %d %d\n', a(i*2-1:i*2,:)');
end
fclose(fid);