Restructure RelTables to support deleting useless information from RelTables.

This commit is contained in:
JCRaymond
2019-12-27 23:24:33 -05:00
parent d2dd002965
commit 9447fc57f7
2 changed files with 105 additions and 40 deletions

View File

@@ -63,6 +63,66 @@ struct RelTable {
}
};
struct RelTablesRow {
int* gnrs;
int** lst_ptrs;
RelTablesRow (int N, int* gnrs, int** lst_ptrs): gnrs(gnrs), lst_ptrs(lst_ptrs) {
for (int i = 0; i < N; i++) {
lst_ptrs[i] = nullptr;
}
}
};
struct TableInfo {
int gens[2];
int mult;
TableInfo(Mult m) {
gens[0] = m.gen0;
gens[1] = m.gen1;
mult = m.mult;
}
};
struct RelTables {
static const int ROW_BLOCK_SIZE = 128;
std::vector<TableInfo> table_info;
std::vector<RelTablesRow*> rows;
int start = 0;
int num_tables;
int buffer_rows = 0;
RelTables (std::vector<Mult> mults): num_tables(mults.size()) {
for (Mult m : mults) {
table_info.emplace_back(m);
}
}
void add_row() {
if (buffer_rows == 0) {
int* gnrs_alloc = new int[num_tables*RelTables::ROW_BLOCK_SIZE];
int** lst_ptrs_alloc = new int*[num_tables*RelTables::ROW_BLOCK_SIZE];
for (int i = 0; i < RelTables::ROW_BLOCK_SIZE; i++) {
rows.push_back(new RelTablesRow(num_tables, &gnrs_alloc[i*num_tables], &lst_ptrs_alloc[i*num_tables]));
}
buffer_rows = RelTables::ROW_BLOCK_SIZE;
}
buffer_rows--;
}
void del_rows_to(int idx) {
const int del_to = (idx/RelTables::ROW_BLOCK_SIZE)*RelTables::ROW_BLOCK_SIZE;
for (int i = start; i < del_to; i += RelTables::ROW_BLOCK_SIZE) {
delete[] rows[i]->gnrs;
delete[] rows[i]->lst_ptrs;
for (int j = 0; j < RelTables::ROW_BLOCK_SIZE; j++) {
delete rows[i+j];
}
start += RelTables::ROW_BLOCK_SIZE;
}
}
};
struct Group {
int ngens;
std::vector<std::vector<int>> _mults;
@@ -138,27 +198,28 @@ struct Group {
}
Cosets cosets(ngens, init_row);
std::vector<RelTable> rel_tables;
RelTables rel_tables(get_mults());
std::vector<std::vector<int>> gen_map(ngens);
int rel_idx;
int rel_idx = 0;
for (Mult m : get_mults()) {
rel_idx = rel_tables.size();
gen_map[m.gen0].push_back(rel_idx);
gen_map[m.gen1].push_back(rel_idx);
rel_tables.emplace_back(m);
rel_idx++;
}
int null_lst_ptr;
for (RelTable &rel : rel_tables) {
int idx = rel.add_row();
rel_tables.add_row();
RelTablesRow &row = *(rel_tables.rows[0]);
for (int table_idx = 0; table_idx < rel_tables.num_tables; table_idx++) {
TableInfo &ti = rel_tables.table_info[table_idx];
if (cosets.get(rel.gens[0]) + cosets.get(rel.gens[1]) == -2) {
rel.lst_ptr[idx] = new int;
rel.gen[idx] = 0;
if (cosets.get(ti.gens[0]) + cosets.get(ti.gens[1]) == -2) {
row.lst_ptrs[table_idx] = new int;
row.gnrs[table_idx] = 0;
}
else {
rel.lst_ptr[idx] = &null_lst_ptr;
rel.gen[idx] = -1;
row.lst_ptrs[table_idx] = &null_lst_ptr;
row.gnrs[table_idx] = -1;
}
}
@@ -168,22 +229,24 @@ struct Group {
while (idx < cosets.data.size() and cosets.get(idx) >= 0)
idx++;
if (idx == cosets.data.size())
if (idx == cosets.data.size()) {
rel_tables.del_rows_to(idx / ngens);
break;
}
target = cosets.len;
cosets.add_row();
rel_tables.add_row();
for (RelTable &rel : rel_tables) {
rel.add_row();
}
std::vector<int> facts;
facts.push_back(idx);
coset = idx / ngens;
gen = idx % ngens;
rel_tables.del_rows_to(coset);
RelTablesRow &target_row = *(rel_tables.rows[target]);
while (!facts.empty()) {
fact_idx = facts.back();
facts.pop_back();
@@ -196,27 +259,28 @@ struct Group {
coset = fact_idx / ngens;
gen = fact_idx % ngens;
for (int rel_idx : gen_map[gen]) {
RelTable &rel = rel_tables[rel_idx];
if ( rel.lst_ptr[target] == nullptr ) {
rel.lst_ptr[target] = rel.lst_ptr[coset];
rel.gen[target] = rel.gen[coset] + 1;
RelTablesRow &coset_row = *(rel_tables.rows[coset]);
for (int table_idx : gen_map[gen]) {
if ( target_row.lst_ptrs[table_idx] == nullptr ) {
TableInfo &ti = rel_tables.table_info[table_idx];
target_row.lst_ptrs[table_idx] = coset_row.lst_ptrs[table_idx];
target_row.gnrs[table_idx] = coset_row.gnrs[table_idx] + 1;
if (rel.gen[coset] < 0)
rel.gen[target] -= 2;
if (coset_row.gnrs[table_idx] < 0)
target_row.gnrs[table_idx] -= 2;
if (rel.gen[target] == rel.mult) {
lst = *(rel.lst_ptr[target]);
delete rel.lst_ptr[target];
gen_ = rel.gens[(int)(rel.gens[0] == gen)];
if (target_row.gnrs[table_idx] == ti.mult) {
lst = *(target_row.lst_ptrs[table_idx]);
delete target_row.lst_ptrs[table_idx];
gen_ = ti.gens[(int)(ti.gens[0] == gen)];
facts.push_back(lst*ngens + gen_);
}
else if (rel.gen[target] == -rel.mult) {
gen_ = rel.gens[rel.gens[0] == gen];
else if (target_row.gnrs[table_idx] == -ti.mult) {
gen_ = ti.gens[ti.gens[0] == gen];
facts.push_back(target*ngens + gen_);
}
else if (rel.gen[target] == rel.mult - 1) {
*(rel.lst_ptr[target]) = target;
else if (target_row.gnrs[table_idx] == ti.mult - 1) {
*(target_row.lst_ptrs[table_idx]) = target;
}
}
}
@@ -224,16 +288,17 @@ struct Group {
std::sort(facts.begin(), facts.end(), std::greater<int>());
}
for (RelTable &rel : rel_tables) {
if (rel.lst_ptr[target] == nullptr) {
if ( (cosets.get(target, rel.gens[0]) != target) and
(cosets.get(target, rel.gens[1]) != target) ) {
rel.lst_ptr[target] = new int;
rel.gen[target] = 0;
for (int table_idx = 0; table_idx < rel_tables.num_tables; table_idx++) {
TableInfo &ti = rel_tables.table_info[table_idx];
if (target_row.lst_ptrs[table_idx] == nullptr) {
if ( (cosets.get(target, ti.gens[0]) != target) and
(cosets.get(target, ti.gens[1]) != target) ) {
target_row.lst_ptrs[table_idx] = new int;
target_row.gnrs[table_idx] = 0;
}
else {
rel.lst_ptr[target] = &null_lst_ptr;
rel.gen[target] = -1;
target_row.lst_ptrs[table_idx] = &null_lst_ptr;
target_row.gnrs[table_idx] = -1;
}
}
}

View File

@@ -3,7 +3,7 @@
#include <iostream>
int main() {
Group g = T(4500);
Group g = B(8);
auto s = std::chrono::system_clock::now();
auto cosets = g.solve();