Hi r-expert, How do I plot this 2 histogram side by side so that it is easy to compare for bin range 0,5,10,15, 20 and more obs_data pre_gam [1,] 2695 2677.284 [2,] 43 61.101 [3,] 20 29.016 [4,] 14 11.160 [5,] 18 11.439 Thanks in advance.