$ perl -wE 'printf qq[%9f\t%.0f\t%2.0f\n], ($_ + 0.5) x 3 for 0 .. 10;' 0.500000 0 0 1.500000 2 2 2.500000 2 2 3.500000 4 4 4.500000 4 4 5.500000 6 6 6.500000 6 6 7.500000 8 8 8.500000 8 8 9.500000 10 10 10.500000 10 10