Then I opened the cheby.ps file in a text editor to edit the line colors and linestyles, as per this descriptionarchive copy at the Wayback Machine. This avoids needing to open in proprietary software, and really isn't that difficult (especially if you don't know the commands in the proprietary software either). ;-) Identify the lines easily by their color (the arrow is currently magenta and I want it to be black. Ah, there is the entry with 1 0 1, red + blue = magenta) or by using the gnuplot linestyle−1. (For instance, gnuplot's linestyle 3 corresponds to the ps file's /LT2.) Then you can edit the colors and dashes by hand. I changed the original:
This image, as well as the following text, is derived from Image:Butterworth_response.png. Generated in gnuplot with the following script (save as cheby.plt and then open in gnuplot): <pre> set samples 2001 set terminal postscript enh