A parsable string giving one of the symmetry operations of the
space group in algebraic form. If W is a matrix representation
of the rotational part of the symmetry operation defined by the
positions and signs of x, y and z, and w is a column of
translations defined by the fractions, an equivalent position
X' is generated from a given position X by the equation:
X' = WX + w
(Note: X is used to represent bold_italics_x in International
Tables for Crystallography Vol. A, Section 5)
When a list of symmetry operations is given, it is assumed
that the list contains all the operations of the space
group (including the identity operation) as given by the
representatives of the general position in International
Tables for Crystallography Vol. A.