Documentation for module qs_fb_atomic_halo

public Types:

fb_atomic_halo_list_obj
defines a fb_atomic_halo_list object
fb_atomic_halo_obj
defines a fb_atomic_halo object

public Subroutines/Functions:

SUBROUTINE 
fb_atomic_halo_atom_global2halo (atomic_halo, iatom_global, iatom_halo, found)
Given a global atomic index, convert it to its index in a given atomic halo, if found. The atomic_halo object must already have been sorted
SUBROUTINE 
fb_atomic_halo_build_halo_atoms (owner_atom, particle_set, cell, pair_radii, halo_atoms, nhalo_atoms, owner_id_in_halo)
Builds halo atoms for a given (owner) atom

              FUNCTION 
              REAL(dp)

            
fb_atomic_halo_cost (atomic_halo, particle_set, qs_kind_set)
Estimates the computational cost with respect to the filter matrix calculation associated to an atomic halo. Given the bottle neck of the filter matrix generation will be the diagoanlisation of the atomic matrices (each consists of atoms in an atomic halo), the cost can be estimated by counting the total number of contracted gaussians in the halo
SUBROUTINE 
fb_atomic_halo_create (atomic_halo)
Creates and initialises an empty fb_atomic_halo object
SUBROUTINE 
fb_atomic_halo_get (atomic_halo, owner_atom, owner_id_in_halo, natoms, nelectrons, halo_atoms, sorted, cost)
Gets attributes from a fb_atomic_halo object, one should only access the data content in a fb_atomic_halo outside this module via this procedure.

              FUNCTION 
              LOGICAL

            
fb_atomic_halo_has_data (atomic_halo)
Checks if a fb_atomic_halo object is associated with an actual data content or not
SUBROUTINE 
fb_atomic_halo_init (atomic_halo)
Initialises an fb_atomic_halo object, and makes it empty
SUBROUTINE 
fb_atomic_halo_list_associate (a, b)
Associates one fb_atomic_halo_list object to another
SUBROUTINE 
fb_atomic_halo_list_create (atomic_halos)
Creates and initialises an empty fb_atomic_halo_list object
SUBROUTINE 
fb_atomic_halo_list_get (atomic_halos, nhalos, max_nhalos, halos)
Gets attributes from an fb_atomic_halo_list object, one should only access the data content in a fb_atomic_halo_list outside this module via this procedure.

              FUNCTION 
              LOGICAL

            
fb_atomic_halo_list_has_data (atomic_halos)
Checks if a fb_atomic_halo_list object is associated with an actual data content or not
SUBROUTINE 
fb_atomic_halo_list_nullify (atomic_halos)
Nullifies a fb_atomic_halo_list object, note that it does not release the original object. This procedure is used to nullify the pointer contained in the object which is used to associate to the actual object content
SUBROUTINE 
fb_atomic_halo_list_release (atomic_halos)
Releases an fb_atomic_halo_list object
SUBROUTINE 
fb_atomic_halo_list_retain (atomic_halos)
Retains an fb_atomic_halo_list object
SUBROUTINE 
fb_atomic_halo_list_set (atomic_halos, nhalos, max_nhalos, halos)
Sets attributes from an fb_atomic_halo_list object, one should only set the data content in a fb_atomic_halo_list outside this module via this procedure.
SUBROUTINE 
fb_atomic_halo_list_write_info (atomic_halos, para_env, scf_section)
Writes out the atomic halo list summary, no detailed neighbour lists, just average, min and max number of halo atoms in the halo list

              FUNCTION 
              INTEGER

            
fb_atomic_halo_nelectrons_estimate_z (atomic_halo, particle_set)
Estimates the total number of electrons in a halo using atomic numbers
SUBROUTINE 
fb_atomic_halo_nullify (atomic_halo)
Nullifies a fb_atomic_halo object, note that it does not release the original object. This procedure is used to nullify the pointer contained in the object which is used to associate to the actual object content
SUBROUTINE 
fb_atomic_halo_release (atomic_halo)
Releases an fb_atomic_halo object
SUBROUTINE 
fb_atomic_halo_set (atomic_halo, owner_atom, owner_id_in_halo, natoms, nelectrons, halo_atoms, sorted, cost)
Sets attributes in a fb_atomic_halo object, one should only set the data content in a fb_atomic_halo from outside this module via this procedure.
SUBROUTINE 
fb_atomic_halo_sort (atomic_halo)
Sort the list of atomic indices in the halo in accending order. The atomic_halo must not be empty

              SUBROUTINE 
              PURE
            
fb_build_pair_radii (rcut, nkinds, pair_radii)
Builds the required pair_radii array required for building the halo atoms from a given set of cut off radii

TYPE :: fb_atomic_halo_list_obj
^

defines a fb_atomic_halo_list object

TYPE(fb_atomic_halo_list_data),

POINTER, PRIVATE

::

obj

...

TYPE :: fb_atomic_halo_obj
^

defines a fb_atomic_halo object

TYPE(fb_atomic_halo_data),

POINTER, PRIVATE

::

obj

...

SUBROUTINEfb_atomic_halo_atom_global2halo(atomic_halo, iatom_global, iatom_halo, found)
^

Given a global atomic index, convert it to its index in a given atomic halo, if found. The atomic_halo object must already have been sorted

Arguments:

TYPE(fb_atomic_halo_obj),	INTENT(in)	::	atomic_halo	the atomic_halo object
INTEGER,	INTENT(in)	::	iatom_global	the global atomic index
INTEGER,	INTENT(out)	::	iatom_halo	the atomic index inside the halo
LOGICAL,	INTENT(out)	::	found	returns true if given atom is in the halo, otherwise false

SUBROUTINEfb_atomic_halo_build_halo_atoms(owner_atom, particle_set, cell, pair_radii, halo_atoms, nhalo_atoms, owner_id_in_halo)
^

Builds halo atoms for a given (owner) atom

Arguments:

INTEGER,	INTENT(in)		::	owner_atom	the atom the halo is going to be built for
TYPE(particle_type),	INTENT(in)		::	particle_set(:)	an array of cp2k particle set objects, this provides atomic information
TYPE(cell_type),		POINTER	::	cell	cp2k cell object, used for resolving periodic boundary conditions
REAL(dp),	INTENT(in)		::	pair_radii(:,:)	2D array storing interaction radii between two kinds
INTEGER,		POINTER	::	halo_atoms(:)	must be NULL pointer on input, and outputs an array of halo atoms corresponding to the owner atom
INTEGER,	INTENT(out)		::	nhalo_atoms	outputs number of halo atoms
INTEGER,	INTENT(out)		::	owner_id_in_halo	the index of the owner atom in the halo_atoms list

FUNCTIONfb_atomic_halo_cost(atomic_halo, particle_set, qs_kind_set)
^

Estimates the computational cost with respect to the filter matrix calculation associated to an atomic halo. Given the bottle neck of the filter matrix generation will be the diagoanlisation of the atomic matrices (each consists of atoms in an atomic halo), the cost can be estimated by counting the total number of contracted gaussians in the halo

Return Value :: REAL(dp): computation cost w.r.t. the filter matrix calculation for this atomic halo

Arguments:

TYPE(fb_atomic_halo_obj),	INTENT(in)	::	atomic_halo	the atomic_halo object in question
TYPE(particle_type),	INTENT(in)	::	particle_set(:)	an array of cp2k particle set objects, this provides atomic information
TYPE(qs_kind_type),	INTENT(in)	::	qs_kind_set(:)	cp2k qs_kind objects, provides information on the number of contracted gaussian functions each kind has

SUBROUTINEfb_atomic_halo_create(atomic_halo)
^

Creates and initialises an empty fb_atomic_halo object

Arguments:

          TYPE(fb_atomic_halo_obj),

          INTENT(inout)

           :: 
          atomic_halo
          the fb_atomic_halo object, its content must be NULL and cannot be UNDEFINED

SUBROUTINEfb_atomic_halo_get(atomic_halo, owner_atom, owner_id_in_halo, natoms, nelectrons, halo_atoms, sorted, cost)
^

Gets attributes from a fb_atomic_halo object, one should only access the data content in a fb_atomic_halo outside this module via this procedure.

Arguments:

TYPE(fb_atomic_halo_obj),	INTENT(in)		::	atomic_halo	the fb_atomic_halo object, its content must not be NULL or UNDEFINED
INTEGER,	INTENT(out),	OPTIONAL	::	owner_atom	if present, outputs atmic_halo%obj%owner_atom
INTEGER,	INTENT(out),	OPTIONAL	::	owner_id_in_halo	...
INTEGER,	INTENT(out),	OPTIONAL	::	natoms	if present, outputs atomic_halo%obj%natoms
INTEGER,	INTENT(out),	OPTIONAL	::	nelectrons	if present, outputs atomic_halo%obj%nelectrons
INTEGER,		OPTIONAL, POINTER	::	halo_atoms(:)	if present, outputs pointer atomic_halo%obj%halo_atoms
LOGICAL,	INTENT(out),	OPTIONAL	::	sorted	if present, outputs atomic_halo%obj%sorted
REAL(dp),	INTENT(out),	OPTIONAL	::	cost	if present, outputs atomic_halo%obj%cost

FUNCTIONfb_atomic_halo_has_data(atomic_halo)
^

Checks if a fb_atomic_halo object is associated with an actual data content or not

Return Value :: LOGICAL

Arguments:

          TYPE(fb_atomic_halo_obj),

          INTENT(in)

           :: 
          atomic_halo
          the fb_atomic_halo object

SUBROUTINEfb_atomic_halo_init(atomic_halo)
^

Initialises an fb_atomic_halo object, and makes it empty

Arguments:

          TYPE(fb_atomic_halo_obj),

          INTENT(inout)

           :: 
          atomic_halo
          the fb_atomic_halo object, its content must not be NULL or UNDEFINED

SUBROUTINEfb_atomic_halo_list_associate(a, b)
^

Associates one fb_atomic_halo_list object to another

Arguments:

TYPE(fb_atomic_halo_list_obj),	INTENT(out)		::	a	the fb_atomic_halo_list object to be associated
TYPE(fb_atomic_halo_list_obj),	INTENT(in)		::	b	the fb_atomic_halo_list object that a is to be associated to

SUBROUTINEfb_atomic_halo_list_create(atomic_halos)
^

Creates and initialises an empty fb_atomic_halo_list object

Arguments:

          TYPE(fb_atomic_halo_list_obj),

          INTENT(inout)

           :: 
          atomic_halos
          the fb_atomic_halo object, its content must not be NULL or UNDEFINED

SUBROUTINEfb_atomic_halo_list_get(atomic_halos, nhalos, max_nhalos, halos)
^

Gets attributes from an fb_atomic_halo_list object, one should only access the data content in a fb_atomic_halo_list outside this module via this procedure.

Arguments:

TYPE(fb_atomic_halo_list_obj),	INTENT(in)		::	atomic_halos	the fb_atomic_halo object, its content must not be NULL or UNDEFINED
INTEGER,	INTENT(out),	OPTIONAL	::	nhalos	if present, gives nhalos = atomic_halos%obj%nhalos
INTEGER,	INTENT(out),	OPTIONAL	::	max_nhalos	if present, gives max_nhalos = atomic_halos%obj%max_nhalos
TYPE(fb_atomic_halo_obj),		OPTIONAL, POINTER	::	halos(:)	if present, gives halos => atomic_halos%obj%halos

FUNCTIONfb_atomic_halo_list_has_data(atomic_halos)
^

Checks if a fb_atomic_halo_list object is associated with an actual data content or not

Return Value :: LOGICAL

Arguments:

          TYPE(fb_atomic_halo_list_obj),

          INTENT(in)

           :: 
          atomic_halos
          the fb_atomic_halo_list object

SUBROUTINEfb_atomic_halo_list_nullify(atomic_halos)
^

Nullifies a fb_atomic_halo_list object, note that it does not release the original object. This procedure is used to nullify the pointer contained in the object which is used to associate to the actual object content

Arguments:

          TYPE(fb_atomic_halo_list_obj),

          INTENT(inout)

           :: 
          atomic_halos
          the fb_atomic_halo_list object

SUBROUTINEfb_atomic_halo_list_release(atomic_halos)
^

Releases an fb_atomic_halo_list object

Arguments:

          TYPE(fb_atomic_halo_list_obj),

          INTENT(inout)

           :: 
          atomic_halos
          the fb_atomic_halo object, its content must not be UNDEFINED, and does nothing if it is NULL

SUBROUTINEfb_atomic_halo_list_retain(atomic_halos)
^

Retains an fb_atomic_halo_list object

Arguments:

          TYPE(fb_atomic_halo_list_obj),

          INTENT(in)

           :: 
          atomic_halos
          the fb_atomic_halo object, its content must not be NULL or UNDEFINED

SUBROUTINEfb_atomic_halo_list_set(atomic_halos, nhalos, max_nhalos, halos)
^

Sets attributes from an fb_atomic_halo_list object, one should only set the data content in a fb_atomic_halo_list outside this module via this procedure.

Arguments:

TYPE(fb_atomic_halo_list_obj),	INTENT(inout)		::	atomic_halos	the fb_atomic_halo object, its content must not be NULL or UNDEFINED
INTEGER,	INTENT(in),	OPTIONAL	::	nhalos	if present, sets atomic_halos%obj%nhalos = nhalos
INTEGER,	INTENT(in),	OPTIONAL	::	max_nhalos	if present, sets atomic_halos%obj%max_nhalos = max_nhalos
TYPE(fb_atomic_halo_obj),		OPTIONAL, POINTER	::	halos(:)	if present, reallocates atomic_halos%obj%halos to the size of halos

SUBROUTINEfb_atomic_halo_list_write_info(atomic_halos, para_env, scf_section)
^

Writes out the atomic halo list summary, no detailed neighbour lists, just average, min and max number of halo atoms in the halo list

Arguments:

TYPE(fb_atomic_halo_list_obj),	INTENT(in)		::	atomic_halos	the fb_atomic_halo object
TYPE(cp_para_env_type),		POINTER	::	para_env	pointer to a para_env_type object containing MPI info
TYPE(section_vals_type),		POINTER	::	scf_section	pointer to the scf input section

FUNCTIONfb_atomic_halo_nelectrons_estimate_z(atomic_halo, particle_set)
^

Estimates the total number of electrons in a halo using atomic numbers

Return Value :: INTEGER: estimate of electron number

Arguments:

TYPE(fb_atomic_halo_obj),	INTENT(in)		::	atomic_halo	the atomic_halo object
TYPE(particle_type),	INTENT(in)		::	particle_set(:)	an array of cp2k particle set objects (this gives atomic information)

SUBROUTINEfb_atomic_halo_nullify(atomic_halo)
^

Nullifies a fb_atomic_halo object, note that it does not release the original object. This procedure is used to nullify the pointer contained in the object which is used to associate to the actual object content

Arguments:

          TYPE(fb_atomic_halo_obj),

          INTENT(inout)

           :: 
          atomic_halo
          the fb_atomic_halo object

SUBROUTINEfb_atomic_halo_release(atomic_halo)
^

Releases an fb_atomic_halo object

Arguments:

          TYPE(fb_atomic_halo_obj),

          INTENT(inout)

           :: 
          atomic_halo
          the fb_atomic_halo object, its content must not be UNDEFINED, and the subroutine does nothing if the content points to NULL

SUBROUTINEfb_atomic_halo_set(atomic_halo, owner_atom, owner_id_in_halo, natoms, nelectrons, halo_atoms, sorted, cost)
^

Sets attributes in a fb_atomic_halo object, one should only set the data content in a fb_atomic_halo from outside this module via this procedure.

Arguments:

TYPE(fb_atomic_halo_obj),	INTENT(inout)		::	atomic_halo	the fb_atomic_halo object, its content must not be NULL or UNDEFINED
INTEGER,	INTENT(in),	OPTIONAL	::	owner_atom	if present, sets atmic_halo%obj%owner_atom = owner_atom
INTEGER,	INTENT(in),	OPTIONAL	::	owner_id_in_halo	...
INTEGER,	INTENT(in),	OPTIONAL	::	natoms	if present, sets atomic_halo%obj%natoms = natoms
INTEGER,	INTENT(in),	OPTIONAL	::	nelectrons	if present, sets atomic_halo%obj%nelectrons = nelectrons
INTEGER,		OPTIONAL, POINTER	::	halo_atoms(:)	if present, reallocates atomic_halo%obj%halo_atoms to the size of halo_atoms, and copies contents of halo_atoms to atomic_halo%obj%halo_atoms
LOGICAL,	INTENT(in),	OPTIONAL	::	sorted	if present, sets atomic_halo%obj%sorted = sorted
REAL(dp),	INTENT(in),	OPTIONAL	::	cost	if present, sets atomic_halo%obj%cost = cost

SUBROUTINEfb_atomic_halo_sort(atomic_halo)
^

Sort the list of atomic indices in the halo in accending order. The atomic_halo must not be empty

Arguments:

          TYPE(fb_atomic_halo_obj),

          INTENT(inout)

           :: 
          atomic_halo
          the atomic_halo object

PURE SUBROUTINEfb_build_pair_radii(rcut, nkinds, pair_radii)
^

Builds the required pair_radii array required for building the halo atoms from a given set of cut off radii

Arguments:

REAL(dp),	INTENT(in)	::	rcut(:)	rcut(ikind) is the cutoff radii for determining the halo corresponding to atomic kind ikind
INTEGER,	INTENT(in)	::	nkinds	total number of atomic kinds in rcut
REAL(dp),	INTENT(out)	::	pair_radii(:,:)	output array pair_radii(ikind,jkind) gives the corresponding interaction range between a pair of atoms of kinds ikind and jkind

TYPE :: fb_atomic_halo_data
^

derived type containing the list of atoms in an atomic halo, used by filtered-basis diagonalisation method

INTEGER		::	id_nr	unique id for the object
INTEGER		::	ref_count	reference count on the object
INTEGER		::	owner_atom	global atomic id of the atom this halo belongs to
INTEGER		::	owner_id_in_halo	index of the owner_atom in the halo_atoms array
INTEGER		::	natoms	number of atoms in the halo
INTEGER		::	nelectrons	estimate of total number of electrons in halo
INTEGER,	DIMENSION(:), POINTER	::	halo_atoms	the list of global id of atoms in the halo
LOGICAL		::	sorted	whether the halo_atoms list is sorted or not
REAL(dp)		::	cost	computational cost for the atomic matrix associated to this atomic halo

TYPE :: fb_atomic_halo_list_data
^

derived type describing an atomic halo list used by filtered-basis diagonalisation method

INTEGER		::	id_nr	unique id for the object
INTEGER		::	ref_count	reference count on the object
INTEGER		::	nhalos	number of halos in the list
INTEGER		::	max_nhalos	maximum of the number of halos amongst all of the procs
TYPE(fb_atomic_halo_obj),	DIMENSION(:), POINTER	::	halos	halos(ihalo) gives the ihalo-th fb_atomic_halo object