Question

For instance, given the following data file (x^2 for this example):

0
1
4
9
16
25

Can gnuplot plot the points along with the differences between the points as if it were:

0 0
1 1   # ( 1 - 0 = 1)
4 3   # ( 4 - 1 = 3)
9 5   # ( 9 - 4 = 5)
16 7  # (16 - 9 = 7)
25 9  # (25 -16 = 9)

The actual file has more than just the column I’m interested in and I would like to avoid pre-processing in order to add the deltas, if possible.

Answer 1

How about using awk?

plot "< awk '{print $1,$1-prev; prev=$1}' <datafilename>"