1No values, binwidth 0 should fail.
2No values, binwidth 1 should fail.
3One value, binwidth 1:
4( 1 )
51, 2, 3, 4, 5, binwidth 1:
6( 1 2 3 4 5 )
71, 2, 3, 4, 5, binwidth 2:
8( 1.5 2.5 3.5 4.5 )
9