Introduction to LINE: a Feynman diagram graphic generator
B. LeClaire · 1985
This is an exec for making Feynman graphs of amazing complexity with amazing simplicity - once you know how. And knowing how is hopefully quite easy to learn. The LINE exec works iteratively, repeatedly prompting you for the elements of the graph. You tell the exec what kinds of lines (or loops) to draw, and where to put them. Each line is plotted in a 10 x 10 Cartesian coordinate system using two ordered pairs of coordinates, (x/sub 1/,y/sub 1/) and (x/sub 2/,y/sub 2/), as endpoints. The types of lines that can be drawn include fermions, scalars, photons, gluons, W or Z bosons. As each line is added the exec alows you to display the updated picture, and to erase the last line added (if necessary). In this way you can keep going, drawing and erasing, until you have exactly what you want.