square
is a shortcut for creating a window object
representing the square
$[0,r] \times [0,r]$.
It is equivalent to the command
owin(c(0,r),c(0,r))
. unit.square
creates the unit square
$[0,1] \times [0,1]$.
It is equivalent to
square(1)
or square()
or owin(c(0,1),c(0,1))
.
These commands are
included mainly to improve the readability of some code.