It is possible to calling gnuplot directly from perl script and plot the data that processed before in perl program. Just for example.. if I have this data: {56, 57, 56, 55, 54, 53, 54, 56, 58, 59, 61, 52, 53, 54, 55, 56, 57, 55, 55, 54, 45, 46, 48, 49, 50, 51, 52, 53, 56, 57, 58, 59, 54, 53, 53, 45,46,47,48,49} I want to calculate the confidence of interval and plotting it.