Method build

This method builds the preconditioner p according to the requirements made by the user through the methods init and set (see Sections 5.3 and 5.4 for multilevel preconditioners). It is mostly provided for backward compatibility; indeed, it is internally implemented by invoking the two previous methods hierarchy_build and smoothers_build, whose nomenclature would however be somewhat unnatural when dealing with simple one-level preconditioners.

`a`	`type(psb_`x`spmat_type), intent(in)`.
	The sparse matrix structure containing the local part of the matrix to be preconditioned. Note that x must be chosen according to the `real`/`complex`, single/double precision version of AMG4PSBLAS under use. See the PSBLAS User’s Guide for details [21].
`desc_a`	`type(psb_desc_type), intent(in)`.
	The communication descriptor of `a`. See the PSBLAS User’s Guide for details [21].
`info`	`integer, intent(out)`.
	Error code. If no error, 0 is returned. See Section 7 for details.
`amold`	`class(psb_`x`_base_sparse_mat), intent(in), optional`.
	The desired dynamic type for internal matrix components; this allows e.g. running on GPUs; it needs not be the same on all processes. See the PSBLAS User’s Guide for details [21].
`vmold`	`class(psb_`x`_base_vect_type), intent(in), optional`.
	The desired dynamic type for internal vector components; this allows e.g. running on GPUs.
`imold`	`class(psb_i_base_vect_type), intent(in), optional`.
	The desired dynamic type for internal integer vector components; this allows e.g. running on GPUs.

5.5 Method build