To change the paper size, there are two commands,
#(set-default-paper-size "a4")
\paper {
#(set-paper-size "a4")
}
The first command sets the size of all pages. The second command sets the size
of the pages that the \paper block applies to – if the \paper
block is at the top of the file, then it will apply to all pages. If the
\paper block is inside a \book, then the paper size will only
apply to that book.
The following paper sizes are supported: a6, a5, a4,
a3, legal, letter, tabloid.
If the symbol landscape is supplied as an argument to
set-default-paper-size, the pages will be rotated by 90 degrees,
and wider line widths will be set correspondingly.
#(set-default-paper-size "a6" 'landscape)
This page is for LilyPond-2.6.6 (stable-branch).