gnuplot

[luke12]

within gnuplot: how do you extract certain things for plotting. for example let's say I need to plot ax^3+bx^2+cx+d and I have a,b,c,d along with a bunch of other numbers in a text file. how would I arrange this output within my c++ program and then extract it from gnuplot. (i know you can plot x vs y if you just output them as 2 columns) this is all assuming I use the wgnuplot.exe (the actual gui) i haven't figured out how to do all this from my c++ program.