Question

I can’t understand how i can plot coupled data in Gnuplot without writing an input file.

Suppose I have data in this format:

(x_val, y_val)

I would like to do something like:

x <- [x_val_1, x_val_2, ... x_val_n]
y <- [y_val_1, y_val_2, ... y_val_n]
plot x y

Is it possible? How can I do that?

Answer 1

If I understand you correctly, you can use gnuplot’s "-" pseudo-datafile:

#for documentation, refer to 
# `help plot datafile special-filenames` 
#  at the gnuplot prompt
plot '-' w points
  1 2
  3 4
  5 6
  7 8
  9 10
  11 12
  e

If you’re trying to use gnuplot to calculate the points, then this won’t work. Depending on how you’re calculating the points, you might be able to plot it at a parametric curve.