Allows the user to extract or replace parts of a crystal
object by using crystal names or subscripts.
USAGE:
x[i]
x[i, left=T, right=T] <- value
x[[i]]
REQUIRED ARGUMENTS:
x
an object of class
wp.crystal,
wp.inf.crystal, or
cp.crystal.
i
a vector of crystal names, positive integers or logical flags.
For
[[,
i must be an integer or a crystal name.
OPTIONAL ARGUMENTS:
value
replacement value for the relevant piece of the crystal object.
left
for assignment operator only, a logical flag indicating if the left boundary
coefficients are to be set to zero.
right
for assignment operator only, a logical flag indicating if the right boundary
coefficients are to be set to zero.
VALUE:
x[i] returns an object of class
"wp.molecule" or
"cp.molecule",
inheriting from class
"molecule";
x[[i]]
returns an object of class
"wp.atom" or
"cp.atom".
DETAILS:
Special assignment operator is needed for
wp.inf.crystal objects only.
The default assignment operator is used for
wp.crystal and
cp.crystal
objects.