How to produce graph of an exact border size? - Gnuplot Programming

How to produce graph of an exact border size?

- Position the top, left, bottom, right borders in fractional position within the page.

- The following script set the exact border size.
set lmargin at screen 0.05
set bmargin at screen 0.05
set rmargin at screen 0.95
set tmargin at screen 0.95