Spectrum.select_rho
===================
Advanced command which defines a spherical region of
space from which photons are to be extracted in constructing a detailed
spectrum.  The region is defined by a cylindrical distance, and z height
and azimuth, and a rho coordainate.   This parameter defines the rho coordinate
of the region.

Type
  Double

Unit
  cm

Values
  Condition e.g. greater than 0 or list e.g. [1, 2, 5]

File
  `setup.c <https://github.com/sirocco-rt/sirocco/blob/master/source/setup.c>`_


Parent(s)
  * :ref:`Spectrum.select_location`: spherical_region