DDSCAT calculates scattering in selected directions, and elements of
the scattering matrix are reported in the output
files wxxryykzzz.sca .
The scattering direction is specified through angles 
and 
(not to be confused with the angles 
and 
which specify the
orientation of the target relative to the incident radiation!).
The scattering angle is simply the angle between the incident beam
(along direction 
) and the scattered beam (
for
forward scattering, 
for backscattering).
The scattering angle specifies the orientation of the ``scattering
plane'' relative to the 
plane in the Lab Frame.
When 
the scattering plane is assumed to coincide with the
plane.
When 
the scattering plane is assumed to coincide with
the 
plane.
Within the scattering plane the scattering directions are specified by
.
Scattering directions for which the scattering properties are to
be calculated are set in the file ddscat.par by
specifying one or more scattering planes (determined by the value of )
and for each scattering plane, the number and range of values.
The only limitation is that the number of scattering directions not exceed
the parameter MXSCA in DDSCAT.f (in the code as distributed it
is set to MXSCA=1000).