sc::R12IntsAcc(3)

✨ sc::R12IntsAcc(3) — MPQC ✨

🌸 NAME 🌸

sc::R12IntsAcc — okay so R12IntsAcc is the accumulator that holds transformed (MO) integrals stored as (ijxy), where i, j, x, and, y live in spaces I, J, X, and Y, respectively. 💖

🦋 SYNOPSIS 🦋

#include <r12ia.h>

Inherits sc::SavableState.

Inherited by sc::R12IntsAcc_MemoryGrp, sc::R12IntsAcc_MPIIOFile, and sc::R12IntsAcc_Node0File.

🎀 Public Types 🎀

• enum tbint_type { eri =0, r12 =1, r12t1 =2, r12t2 =3 } — the kinds of two-body operators that R12IntsAcc understands. ✨

👑 Public Member Functions 👑

• R12IntsAcc (int num_te_types, int ni, int nj, int nx, int ny)
• R12IntsAcc (StateIn &)
• void save_data_state (StateOut &) — saves the base classes (with save_data_state) and the members in the same order that the StateIn CTOR initializes them.
• int num_te_types () const — how many types of integrals are being handled together.
• int ni () const — rank of index space i.
• int nj () const — rank of index space j.
• int nx () const — rank of index space x.
• int ny () const — rank of index space y.
• size_t blocksize () const — size of each block of the integrals of one type, in double words.
• int next_orbital () const — the index of the first orbital in the next integrals batch to be stored.
• virtual void store_memorygrp (Ref< MemoryGrp > &mem, int ni, const size_t blksize=0)=0 — stores all pair block of integrals held in mem in a layout assumed throughout MBPT2_R12.
• virtual void store_pair_block (int i, int j, double *ints)=0 — heads-up: for all member functions of this class and its children, the indices i and j don’t include frozen orbitals. Stores an ij pair block of integrals (assumes the block resides locally).
• virtual void commit () — commits the content of the accumulator for reading.
• bool is_committed () — has the content of the accumulator been committed for reading?
• virtual void activate () — call before starting to read content.
• virtual void deactivate () — call when done reading content.
• const bool is_active () — check if you can read content.
• virtual double * retrieve_pair_block (int i, int j, tbint_type oper_type)=0 — retrieves an ij pair block of integrals.
• virtual void release_pair_block (int i, int j, tbint_type oper_type)=0 — releases an ij pair block of integrals (if needed).
• virtual bool is_local (int i, int j) const =0 — is this block stored locally?
• virtual bool is_avail (int i, int j) const =0 — is this block available to this task?
• virtual bool has_access (int proc) const =0 — does this task have access to all the integrals?
• int tasks_with_access (vector< int > &twa_map) const — returns the total number of tasks with access to integrals.
• virtual bool can_restart () const =0 — can this specialization be used in restarts?

💎 Static Public Attributes 💎

• static const int max_num_te_types_ = 4 — this one’s a constant, bestie. ✨

🧚 Protected Member Functions 🧚

• virtual int ntasks () const =0 — total number of tasks.
• virtual int taskid () const =0 — ID of this task.
• void inc_next_orbital (int ni) — this is about the index of the first orbital in the next integrals batch to be stored.

🍓 Protected Attributes 🍓

• int ni_
• int nj_
• int nx_
• int ny_
• size_t nxy_
• size_t blksize_
• size_t blocksize_
• int next_orbital_
• bool committed_
• bool active_

🦋 Additional Inherited Members 🦋

No extra inherited members are listed here. That’s literally it. 🫶

🌈 Detailed Description 🌈

R12IntsAcc accumulates transformed (MO) integrals stored as (ijxy) where i, j, x, and, y lie in spaces I, J, X, and Y, respectively. 🫶

ijxy is only the storage format, the actual type may be (ix|jy), (ij|xy), etc.

Transformed integrals are usually computed using a parallel MO integrals transformation procedure. In general, such transformations will require multiple passes through AO integrals. Each pass produces a batch of transformed integrals. For example, a batch in direct parallel MP2 energy algorithm is a set of integrals {(ix|jy)} in which i indices are in a finite subrange of O and x, j, and y take any of their allowed values. For example, if batch I contains all integrals (ix|jy) with i greater than or equal m but less than n, then batch I+1 contains integrals (ix|jy) with i greater than n. Integrals in batch 0 have indices i greater than or equal to 0. 🔥

After each pass the MO integrals are contained in a MemoryGrp object. The object is 'stored' in accumulator using store_memorygrp(Ref<MemoryGrp>& mem, int ni). After all batches have been stored, the content of R12IntsAcc needs to be 'committed' using commit(). After that blocks of MO integrals can be accessed using retrieve_pair_block.

💅 Member Function Documentation 💅

💖 void sc::R12IntsAcc::save_data_state (StateOut &) [virtual]

Save the base classes (with save_data_state) and the members in the same order that the StateIn CTOR initializes them. This must be implemented by the derived class if the class has data. ✨

Reimplemented from sc::SavableState.

Reimplemented in sc::R12IntsAcc_MPIIOFile_Ind, sc::R12IntsAcc_MPIIOFile, sc::R12IntsAcc_Node0File, and sc::R12IntsAcc_MemoryGrp.

🫶 virtual void sc::R12IntsAcc::store_memorygrp (Ref< MemoryGrp > & mem, int ni, const size_t blksize = 0) [pure virtual]

Stores all pair block of integrals held in mem in a layout assumed throughout MBPT2_R12. Let’s suppose the number of tasks is nproc, nj is the number of j indices, ni is the number of i indices of integrals held in mem at the moment. Then all integrals with a given i and j are stored on task (i*nj+j)/nproc and this ij block is (i*nj+j)nproc -th block on this task. Each ij block contains num_te_types_ subblocks of integrals. Each subblock of integrals has blksize bytes allocated for it. Note that blksize may be larger than blksize_ because an ij-block of partially transformed integrals may be larger than the block of fully transformed integrals. 😭

Implemented in sc::R12IntsAcc_MPIIOFile_Ind, sc::R12IntsAcc_Node0File, and sc::R12IntsAcc_MemoryGrp.

🌟 int sc::R12IntsAcc::tasks_with_access (vector< int > & twa_map) const

Returns the total number of tasks with access to integrals. If task i has access to the integrals, then twa_map[i] is its index among the tasks with access, -1 otherwise.

🌸 Author 🌸

Generated automatically by Doxygen for MPQC from the source code.

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🎀 That’s the full page, bestie! Source/version/date sign-off: Version 2.3.1, Sun Oct 4 2020, sc::R12IntsAcc(3). Catch you on the next manpage! 💖✨