set_pixelization

subroutine set_pixelization( int pixchoice, pixparameters pixpars, pixeltype *pixelization)

Purpose:

The routine allocates and defines the S2HAT pixeltype structure, pixelization, for a set of default pixelization schemes. The pixelization choice is decided by the input parameter pixchoice.
The pixelization structure is used for storing all the info about the pixelization and needed for calculating all the transforms later on. It can be done by calling the routine by either all procs, or just one proc, e.g., root, which later broadcasts the structure to all other procs via a call to mpi_pixelizationbcast.

NB. The pixelization structure has to be defined and identical on all the procs for the transforms.


Parameters:

input:

pixchoice-- [integer(4b)], determines the choice of a pixelization scheme, those are defined by a set of standard parameters called PIXCHOICE_xxx (see Section on Parameters);

pixpars-- [type( pixparameters)], define the pixelization parameters (e.g., nside for HEALpix) which is assumed to determine uniquely the pixel properties for the given pixelization as given by pixchoice.

output:

pixelization-- [type( pixeltype)], a S2HAT structure storing all the properties of the pixelization needed by the transforms later on. The field of the structure will be allocated internally by the routine. The structure of the type pixeltype should be first deallocated calling the destroy_pixelization before being defined/allocated again.