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2L_enum.cpp
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2L_enum.cpp
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//
// 2L_enum.cpp
//
// Created by Samuel Fiorini and Marco Macchia
// Purpose: Enumerate all the combinatorial types of 2-level polytopes in dimension D between 3 and 7
//
// REMARKS ON INSTALLATION
// - Install Boost. For more details, refer to http://www.boost.org
// - Compile nauty library, available here http://pallini.di.uniroma1.it
// - The source code here assumes that the header file nauty.h and the following object files are in the source code folder:
// naurng.o, schreier.o, naugraph.o, nautiL.o, nauty1.o
// - Now it is possible to compile this code with
// g++ -g 2L_enum.cpp nautyL.o naurng.o nautil.o schreier.o naugraph.o -o 2L_enum
//
// Info on data structures:
//
// - The 0/1-matrices we use are *nonincidence* matrices, which means that 0 indicates
// incidence while 1 indicates nonincidence. This affects the way sets are manipulated.
//
#include "nauty.h"
#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
#include <map>
#include <algorithm>
#include <chrono>
#define BOOST_UBLAS_NDEBUG 1
//#include <boost/serialization/array_wrapper.hpp>
#include <boost/dynamic_bitset.hpp> // Use Boost's dynamic_bitsets for sets
#include <boost/numeric/ublas/vector.hpp> // Use Boost's basic linear algebra (ublas) vectors
#include <boost/numeric/ublas/matrix.hpp> // Use Boost's basic linear algebra (ublas) matrices
#include <boost/numeric/ublas/io.hpp> // Use Boost's basic linear algebra (ublas) io routines
#include <boost/numeric/ublas/lu.hpp>
// Change the value for D to change the dimension in which the enumeration is performed
// Dimension D, insert a value berween 3 and 7
//#define D 3
// verbose = 0 : minimal output (the benchmarks times correspond to verbose = 0)
// verbose = 1 : output includes all closed sets + tests for classes of 2L polytopes
// verbose = 2 : output includes all closed sets + tests for classes of 2L polytopes
// verbose = 3 : output includes all closed sets, ground sets, slabs_sat_by_point and points_sat_by_slab
// + tests for classes of 2L polytopes
//#define verbose 0
namespace ublas = boost::numeric::ublas;
typedef boost::dynamic_bitset<>::size_type size_type;
size_type npos = boost::dynamic_bitset<>::npos;
// Canonical forms of all nonincidence graphs of (D-1)-dim 2L-poly
// The key value is the hash value of the matrix (for the moment, computed from number of columns and rows)
// The mapped value is the canonical form of the graph as computed by Nauty, which is a vector of setwords
std::multimap<int,std::vector<setword>> atoms_cg;
// List LD of D-dimensional 2-level polytopes
std::multimap<int,std::vector<setword>> LD;
// Counters for the classes of 2L polytopes
int simplicial_facet = 0; // 2L polytopes with a simplicial facet
int cs = 0; // Centrally-symmetric 2L polytopes
int stab = 0; // Stable set polytopes of a perfect graph
int n_suspensions = 0; // 2L suspensions
int n_polar = 0; // Polar 2L polytopes
// output file
std::ofstream myfile;
// Vector of bitsets, giving for each point the set of slabs that are satisfied by it
std::vector<boost::dynamic_bitset<>> slabs_sat_by_point;
// Vector of bitsets, giving for each slab the set of points (in the ground set) that are satisfied by it
std::vector<boost::dynamic_bitset<>> points_sat_by_slab;
// Check if A \sqsubseteq B
bool sqsubseteq(boost::dynamic_bitset<> A, boost::dynamic_bitset<> B) {
assert (A.size() == B.size());
// Check if A is a subset of B
if (A.is_subset_of(B)) {
// find first bit set to 1 in B
// Skip all bits that are set to 0 in A and to 1 in B, and delete them from B
// until a bit is found that is 1 in A and 1 in B. At that point, compare A to B
for (size_type pos = B.find_first(); pos != npos && pos < A.find_first(); pos = B.find_next(pos))
B.flip(pos);
return (A == B);
}
else
return false;
}
boost::dynamic_bitset<> inc(boost::dynamic_bitset<> A, int i) {
assert (i < A.size());
for (size_type pos=A.find_first(); pos != npos && pos<i; pos=A.find_next(pos))
A.flip(pos);
A.set(i);
return A;
}
// Compute the discrete convex hull of a point set A
boost::dynamic_bitset<> discreteconvexhull_cl(const boost::dynamic_bitset<> &A, boost::dynamic_bitset<> &B) {
assert (A.size() == slabs_sat_by_point.size());
//std::cout << "A.size() = " << A.size() << std::endl;
//std::cout << "points_sat_by_slab.size() = " << points_sat_by_slab.size() << std::endl;
//std::cout << "slabs_sat_by_point.size() = " << slabs_sat_by_point.size() << std::endl;
//boost::dynamic_bitset<> B(points_sat_by_slab.size());
boost::dynamic_bitset<> C(slabs_sat_by_point.size());
size_type pos;
// Set all bits of B to 1
B.set();
// Intersect all sets of slabs belonging to elements of A
for (pos = A.find_first(); pos != npos; pos = A.find_next(pos))
B &= slabs_sat_by_point[pos];
//std::cout << "A = " << A << std::endl;
//std::cout << "B = " << B << std::endl;
// Set all bits of C to 1
C.set();
// Intersect all sets of points belonging to elements of B
for (pos = B.find_first(); pos != npos; pos = B.find_next(pos))
C &= points_sat_by_slab[pos];
//std::cout << "C = " << C << std::endl;
return C;
}
// incompatibility closure operator
boost::dynamic_bitset<> incompatibility_cl(const std::vector<boost::dynamic_bitset<>> &incompatibility_adjM,boost::dynamic_bitset<> &A) {
if (A.count() > 1) { // if A has less than 2 points, then A = {e_1}
bool accept = true;
for (size_type i = A.find_next(0); i != npos && accept; i = A.find_next(i)) {
for (size_type j = A.find_next(0);j != i && accept; j = A.find_next(j))
accept = !(incompatibility_adjM[i].test(j));
}
if (accept)
return A;
else {
boost::dynamic_bitset<> incclA(A.size());
return incclA.set();
}
}
else
return A;
}
// Used for hashing slack matrices: returns (num_cols - 1) * 2^D + (num_rows - 1)
// Assert that S has at least one row and at least one column
int hash_matrix(const std::vector<boost::dynamic_bitset<>> &S, int D) {
// Make sure that the slack matrix has at least one row and column
assert (S.size() > 0);
assert (S[0].size() > 0);
int num_rows = (int) S.size();
int num_cols = (int) S[0].size();
return (((num_cols - 1) << D) + num_rows - 1);
}
// Call Nauty to obtain the canonical form of the nonincidence graph of slack matrix S
std::vector<setword> canonicize(const std::vector<boost::dynamic_bitset<>> &S) {
std::vector<setword> cg_vec;
// Make sure that the slack matrix has at least one row and column
assert (S.size() > 0);
assert (S[0].size() > 0);
// Get the number of rows and columns of current atom
int num_rows = (int) S.size();
int num_cols = (int) S[0].size();
// Initializations for Nauty
DYNALLSTAT(int,lab,lab_sz);
DYNALLSTAT(int,ptn,ptn_sz);
DYNALLSTAT(int,orbits,orbits_sz);
DYNALLSTAT(int,map,map_sz);
DYNALLSTAT(graph,g,g_sz);
DYNALLSTAT(graph,cg,cg_sz);
static DEFAULTOPTIONS_GRAPH(options);
statsblk stats;
// Select option for canonical labelling
options.getcanon = TRUE;
// Select option for custom partition
options.defaultptn = FALSE;
int m, n;
n = num_rows + num_cols;
m = SETWORDSNEEDED(n);
nauty_check(WORDSIZE,m,n,NAUTYVERSIONID);
// Allocate memory for the graph
DYNALLOC1(int,lab,lab_sz,n,"malloc");
DYNALLOC1(int,ptn,ptn_sz,n,"malloc");
DYNALLOC1(int,orbits,orbits_sz,n,"malloc");
DYNALLOC1(int,map,map_sz,n,"malloc");
DYNALLOC2(graph,g,g_sz,n,m,"malloc");
DYNALLOC2(graph,cg,cg_sz,n,m,"malloc");
// Empty the graph
EMPTYGRAPH(g,m,n);
// Build the custom partition for the graph
for (int i = 0; i < num_rows+num_cols; i++) {
lab[i] = i;
if (i != num_rows-1 && i != num_rows+num_cols-1)
ptn[i] = 1;
else
ptn[i] = 0;
}
// Build the edges of the nonincidence graph
// Loop through all the entries of the slack matrix and add an edge when there is a one
for (int i = 0; i < num_rows; i++) {
for (int j = 0; j < num_cols; j++) {
if ((S[i])[j] == 1)
ADDONEEDGE(g,i,j+num_rows,m);
}
}
// Obtain canonical graph from Nauty
densenauty(g,lab,ptn,orbits,&options,&stats,m,n,cg);
// Make std::vector<setword> from canonical graph
for (size_t k = 0; k < m*(size_t)n; ++k)
cg_vec.push_back(cg[k]);
// Clean up
DYNFREE(lab,lab_sz);
DYNFREE(ptn,ptn_sz);
DYNFREE(orbits,orbits_sz);
DYNFREE(map,map_sz);
DYNFREE(g,g_sz);
DYNFREE(cg,cg_sz);
return cg_vec;
}
// Checks whether a given 0-1 matrix has a (d+1) x (d+1) lower triangular nonsingular submatrix
// at the top left corner
bool checksimplicialcore(const std::vector<boost::dynamic_bitset<>> &S, int d) {
bool test = true;
// Check that S has at least d rows
assert (S.size() >= d);
for (int i=0; i<=d && test; ++i) {
// Check that the ith row of S has at least d columns
assert (S[i].size() >= d);
for (int j=i; j<=d && test; ++j) {
if (i == j)
test = ((S[i])[j] == 1);
else if (i < j)
test = ((S[i])[j] == 0);
}
}
return test;
}
// Extract extended embedding transformation matrix M_d(0) from simplicial core
ublas::matrix<int> extractM(std::vector<boost::dynamic_bitset<>> S, int d) {
ublas::matrix<int> M(d,d);
// Check that S has at least d rows
assert (S.size() >= d);
for (int i=0; i<d; ++i) {
// Check that the ith row of S has at least d columns
assert (S[i].size() >= d);
for (int j=0; j<d; ++j) {
if (i == 0 && j == 0)
M(i,j) = 1;
else if (i == 0 || j == 0)
M(i,j) = 0;
else
M(i,j) = (S[i-1])[j-1];
}
}
return M;
}
bool invertM(const ublas::matrix<int> &M, ublas::matrix<int> &Minv) {
// Create a duplicate of the input matrix
ublas::matrix<size_type> W = M;
assert (W.size1() == W.size2());
size_type d = W.size1();
// Create the permutation matrix
ublas::permutation_matrix<size_type> P(d);
Minv.resize(d,d);
// Assign the identity matrix to the inverse
Minv.assign(ublas::identity_matrix<int>(d));
// LU factorization and substitution
size_type res = lu_factorize(W, P);
if (res != 0)
return false;
lu_substitute(W,P,Minv);
return true;
}
// slack matrix construction
std::vector<boost::dynamic_bitset<>> construct_slack_matrix(const std::vector<ublas::vector<int>> &base_H,const std::vector<ublas::vector<int>> &ground_set_H,const boost::dynamic_bitset<> &A,const boost::dynamic_bitset<> &B,const std::vector<ublas::vector<int>> &slabs, const std::vector<boost::dynamic_bitset<>> &S, std::vector<boost::dynamic_bitset<>> &S_new, int &D) {
std::vector<boost::dynamic_bitset<>> all_ineqs;
for (size_type i = B.find_first(); i != npos; i = B.find_next(i)){
// constuct each row of S with column indexed by e_1, the vertices of the base and then the remaining ones
// in this way the first D+1 columns will be the H-embedding of the canonical affine base of R^D.
boost::dynamic_bitset<> S_row;
int s = ublas::inner_prod(ground_set_H[0],slabs[i]);
bool slack1 = (s != 0);
S_row.push_back(slack1);
for (std::vector<ublas::vector<int>>::const_iterator it=base_H.begin(); it!=base_H.end(); it++) {
int s = ublas::inner_prod(*it,slabs[i]);
bool slack1 = (s != 0);
S_row.push_back(slack1);
}
for (size_type j = A.find_next(0); j != npos; j = A.find_next(j)){
int s = ublas::inner_prod(ground_set_H[j],slabs[i]);
bool slack1 = (s != 0);
S_row.push_back(slack1);
}
if ((~S_row).count() >= D)
all_ineqs.push_back(S_row);
if (S_row.count() >= D)
all_ineqs.push_back(~S_row);
}
// check maximality of rows
std::vector<boost::dynamic_bitset<>>::iterator it1,it2;
for (it1=all_ineqs.begin(); it1!=all_ineqs.end(); ++it1) {
bool is_maximal = true;
for (it2=all_ineqs.begin(); it2!=all_ineqs.end() && is_maximal; ++it2) {
if ((*it2).is_subset_of(*it1) && it2!=it1)
is_maximal = false;
}
if (is_maximal)
S_new.push_back(*it1);
}
// rearranging rows of S
int n_row = 0;
for (std::vector<boost::dynamic_bitset<>>::iterator it = S_new.begin()+n_row+1; it != S_new.end(); it++) {
//for (std::vector<boost::dynamic_bitset<>>::iterator print = S.begin(); print != S.end(); print++)
// std::cout << *print << std::endl;
//std::cout << n_row + 1 << std::endl;
bool accept = true;
for (size_type j = 0; j < S[0].size() && n_row < D && accept; j++)
accept = ((*it).test(j+1) == (S[n_row]).test(j));
if (accept) {
swap(*it, S_new[n_row+1]);
++n_row;
}
}
/*
// debugging
std::cout << S_new[0].size() << ',' << S_new.size() << ' ';
std::cout << std::endl;
for (std::vector<boost::dynamic_bitset<>>::iterator print = S_new.begin(); print != S_new.end(); print++)
std::cout << *print << std::endl;
std::cout << std::endl;*/
return S_new;
}
// Checks whether a given 0-1 matrix is the slack matrix of a D-dimensional 2-level polytope,
// by using the list of (D-1)-dimensional 2-level polytopes.
bool istwolevelpolytope(std::vector<boost::dynamic_bitset<>> S, int &D) {
// First test: check that every column contains at least D zeros
// by construction, every row of S contains at least D zeros
bool accept = true;
for (size_type it_cols = 0; it_cols != S[0].size() && accept; it_cols++) {
int n_zeros_col = 0;
for (std::vector<boost::dynamic_bitset<>>::iterator it_rows = S.begin(); it_rows != S.end(); it_rows++) {
n_zeros_col += !(*it_rows).test(it_cols);
}
accept = (n_zeros_col >= D);
}
if (!accept)
return false;
std::vector<boost::dynamic_bitset<>>::iterator it1, it2, it3; // iterators to browse rows of matrix
std::vector<std::vector<int>> neighbors; // Collect the indices of neighbors of each row
bool notadjacent;
// Initialize the neighbors data structure with S.size() empty lists.
std::vector<int> empty_neighborhood;
for (it1=S.begin(); it1!=S.end(); ++it1)
neighbors.push_back(empty_neighborhood);
// Dual graph computation
// std::cout << "Dual graph computation..." << std::endl;
// This loop computes the dual graph of S by going through all unordered pairs
// of rows of S (indexed by it1 and it2), and checking whether the union does
// not contain a third row (indexed by it3)
for (it1=S.begin(); it1!=S.end(); ++it1) {
int i1 = (int)distance(S.begin(),it1);
// Compute the neighbor of first row, with bigger index
//std::cout << "New neighbors of " << distance(S.begin(),it1) << ": ";
for (it2=it1+1; it2!=S.end(); ++it2) {
int i2 = (int)distance(S.begin(),it2);
// Compute the union of the two rows
boost::dynamic_bitset<> u = (*it1) | (*it2);
// Go through all the other rows and check whether union contains some other row.
// If such a row is found, that means that the two rows are not adjacent.
notadjacent = false;
for (it3=S.begin(); it3!=S.end() && !notadjacent; ++it3) {
if (it3 != it1 && it3 != it2 && (*it3).is_subset_of(u))
notadjacent = true;
}
// If an adjacency is detected, add the neighbor list of both rows
if (!notadjacent) {
//std::cout << i2 << ' ';
neighbors[i1].push_back(i2);
neighbors[i2].push_back(i1);
}
}
//std::cout << std::endl;
}
//std::cout << std::endl;
// Computation and verification of submatrices
//std::cout << "Computation of submatrices..." << std::endl;
accept = true;
for (std::vector<std::vector<int>>::iterator it=neighbors.begin(); it!=neighbors.end() && accept; it++)
accept = ((*it).size() >= D);
if (!accept)
return false;
bool found = true;
// Once the dual graph is known, go through all the rows and build the corresponding
// submatrix for each of them. If the input is a slack matrix, this will compute the
// slack matrix of the corresponding facet
for (it1=S.begin(); it1!=S.end() && found; ++it1) {
std::vector<boost::dynamic_bitset<>> SS; // submatrix of S corresponding to the row
int i1 = (int)distance(S.begin(),it1);
std::vector<size_type> vert_idx; // column indices in S of zeroes
size_type num_zeroes = 0; // number of columns
// Compute submatrix for current row
//std::cout << "Submatrix for row #" << i1;
// Count the zeroes in the row and record their positions
for (size_type i = 0; i < (*it1).size(); ++i) {
// If a zero is found, record its position
if (!(*it1).test(i)) {
vert_idx.push_back(i);
++num_zeroes;
}
}
// std::cout << " (" << (*it1) << " - " << "#zeroes = " << num_zeroes << ")" << std::endl;
// Go through all neighbors of the row
for (std::vector<int>::iterator it4=neighbors[i1].begin(); it4!=neighbors[i1].end(); ++it4) {
boost::dynamic_bitset<> new_row(num_zeroes);
// Go through all vertices of the row, and collect the bits from the slack matrix
// to form the slack matrix for the row (which is a submatrix of S)
for (size_type i = 0; i < num_zeroes; ++i) {
size_type j = vert_idx[i];
new_row[i] = (S[*it4])[j];
}
// Add new_row to submatrix
SS.push_back(new_row);
//std::cout << new_row << std::endl;
}
// Turn the submatrix into a nonincidence graph, and canonicize it
std::vector<setword> canonical = canonicize(SS);
found = false;
// Obtain range with atoms_cg corresponding to nonincidence graphs with same hash
std::pair <std::multimap<int,std::vector<setword>>::iterator, std::multimap<int,std::vector<setword>>::iterator> r;
r = atoms_cg.equal_range(hash_matrix(SS,D-1));
// Browse through all nonincidence graphs that have the same hash to see if one of them
// is isomorphic to the current nonincidence graph
for (std::multimap<int,std::vector<setword>>::iterator it5=r.first; it5!=r.second && !found; ++it5)
found = ((*it5).second == canonical);
//if (found) {
// std::cout << "OK: nonincidence graph isomorphic to that of an atom" << std::endl;
//}
//else {
// std::cout << "ERROR: nonincidence graph not isomorphic to that of an atom" << std::endl;
//}
//
//std::cout << "-" << std::endl;
}
return found;
}
// Check equality of ublas::vector
bool is_equal(ublas::vector<int> A,ublas::vector<int> B) {
assert(A.size() == B.size());
bool flag = true;
for (size_type it = 0; it != A.size() && flag; it++)
flag = (A[it] == B[it]);
return flag;
}
// test if the 2-level polytope having slack-matrix S_new is a suspension
bool is_susp(std::vector<boost::dynamic_bitset<>> S_new) {
// For all rows i of the slack matrix M
// Partition the columns into F_0 = {j : M(i,j) = 0} and F_1 = {j : M(i,j) = 1}
// For all translation vectors t such that the vertices of F_1 - t are a subset of those of F_0
// Check that F_1 - t is a face by testing whether the intersection of all facets of P that contain it is exactly F_1 - t
bool flag = false;
std::vector<ublas::vector<int>> S_cols; // slack embedding of the polytope having S_new as slack matrix
for (size_type col_idx = 0; col_idx != S_new[0].size(); col_idx++) {
ublas::vector<int> column(S_new.size());
for (int it0 = 0; it0 != S_new.size(); ++it0)
column(it0) = S_new[it0][col_idx];
S_cols.push_back(column);
}
for (std::vector<boost::dynamic_bitset<>>::iterator it0 = S_new.begin(); it0 != S_new.end(); ++it0) {
std::vector<size_type> zeros_idx; // column indices in S of zeroes
std::vector<size_type> ones_idx; // column indices in S of ones
// Count zeroes and ones in the row and record their positions
for (size_type i = 0; i < (*it0).size(); ++i) {
if ((*it0).test(i))
ones_idx.push_back(i);
else
zeros_idx.push_back(i);
}
for (std::vector<size_type>::iterator it1 = ones_idx.begin();it1 != ones_idx.end(); it1++) {
for (std::vector<size_type>::iterator it2 = zeros_idx.begin();it2 != zeros_idx.end(); it2++) {
ublas::vector<int> translation_vect = S_cols[*it2] - S_cols[*it1];
bool is_contained = true;
std::vector<size_type> idx_translated_F1;
for (std::vector<size_type>::iterator it3 = ones_idx.begin();it3 != ones_idx.end() && is_contained; it3++) {
ublas::vector<int> translated_F1_point = S_cols[*it3] + translation_vect;
bool is_found = false;
for (int h = 0; h != zeros_idx.size() && !is_found; h++) {
is_found = (is_equal(translated_F1_point,S_cols[zeros_idx[h]]));
if (is_found)
idx_translated_F1.push_back(zeros_idx[h]);
}
is_contained &= is_found;
}
if (is_contained) {
boost::dynamic_bitset<> char_F1(S_new[0].size());
char_F1.set();
for (int h = 0; h != idx_translated_F1.size(); h++)
char_F1.flip(idx_translated_F1[h]);
boost::dynamic_bitset<> intersect_rows_containing_F1(S_new[0].size());
for (std::vector<boost::dynamic_bitset<>>::iterator it0 = S_new.begin(); it0 != S_new.end(); ++it0) {
if ((*it0).is_subset_of(char_F1))
intersect_rows_containing_F1 |= *it0;
}
flag = (intersect_rows_containing_F1 == char_F1);
}
}
}
}
return flag;
}
// Test if the polar of the 2-level polytope having slack-matrix S_new is a still 2_level
int is_polar(std::vector<boost::dynamic_bitset<>> S_new,int &D) {
std::vector<boost::dynamic_bitset<>> S_transpose;
for (size_type col_idx = 0; col_idx != S_new[0].size(); col_idx++) {
boost::dynamic_bitset<> column;
for (size_type row_idx = 0; row_idx != S_new.size(); row_idx++)
column.push_back(S_new[row_idx][col_idx]);
S_transpose.push_back(column);
}
int hash_S = hash_matrix(S_new,D);
int hash_S_T = hash_matrix(S_transpose,D);
std::vector<setword> canonical_S_T = canonicize(S_transpose);
int amount_polar = 0;
if (hash_S == hash_S_T) {
if (canonicize(S_new) == canonical_S_T)
amount_polar = 1; // self-polar
}
else {
bool is_isomorphic = false;
std::pair <std::multimap<int,std::vector<setword>>::iterator, std::multimap<int,std::vector<setword>>::iterator> r;
r = LD.equal_range(hash_S_T);
// Browse through all nonincidence graphs that have the same hash to see if one of them
// is isomorphic to the current nonincidence graph
for (std::multimap<int,std::vector<setword>>::iterator it1=r.first; it1!=r.second && !is_isomorphic; ++it1)
is_isomorphic = ((*it1).second == canonical_S_T);
if (is_isomorphic)
amount_polar = 2;
}
return amount_polar;
}
// check if the slack matrix S is already listed in LD; if not, add it to LD
void to_list(std::vector<boost::dynamic_bitset<>> S_new, int &D, const int &verbose){
int hash_S = hash_matrix(S_new,D);
std::vector<setword> canonical_S = canonicize(S_new);
bool is_isomorphic = false;
// Obtain range with atoms_cg corresponding to nonincidence graphs with same hash
std::pair <std::multimap<int,std::vector<setword>>::iterator, std::multimap<int,std::vector<setword>>::iterator> r;
r = LD.equal_range(hash_S);
// Browse through all nonincidence graphs that have the same hash to see if one of them
// is isomorphic to the current nonincidence graph
for (std::multimap<int,std::vector<setword>>::iterator it1=r.first; it1!=r.second && !is_isomorphic; ++it1)
is_isomorphic = ((*it1).second == canonical_S);
if (!is_isomorphic) {
LD.insert(std::pair<int,std::vector<setword>>(hash_S,canonical_S));
for (std::vector<boost::dynamic_bitset<>>::iterator it2 = S_new.begin(); it2 != S_new.end(); ++it2)
myfile << *it2 << std::endl;
myfile << '-' << std::endl;
if (verbose != 0) {
// check is there exists a simplicial facet
bool has_simplicial = false;
for (std::vector<boost::dynamic_bitset<>>::iterator row = S_new.begin(); row != S_new.end() && !has_simplicial; row++)
has_simplicial = ((~*row).count() == D);
if (has_simplicial)
simplicial_facet++;
// check if there exists a simple vertex
bool STAB = false;
for (size_type col_idx = 0; col_idx != S_new[0].size() && !STAB; col_idx++) {
boost::dynamic_bitset<> column;
for (int it0 = 0; it0 != S_new.size(); ++it0)
column.push_back(S_new[it0][col_idx]);
STAB = ((~column).count() == D);
}
if (STAB)
stab++;
// check if the polytope is centrally symmetric
bool CS = true;
for (std::vector<boost::dynamic_bitset<>>::iterator row = S_new.begin(); row != S_new.end() && CS; row++)
CS = ((*row).count() == S_new[0].size()/2);
if (CS)
cs++;
// tests if the polytope is a suspension
if (is_susp(S_new))
n_suspensions++;
// tests if the polytope has a polar that is a polytope
n_polar+=is_polar(S_new,D);
}
}
}
int main(int argc, const char *argv[]) {
if (argc != 3) {
std::cout << "\nERROR: Wrong input, not enough arguments" << std::endl;
std::cout << "Please insert two arguments: dimension D, verbose_flag." << std::endl;
std::cout << "- D is an integer between 3 and 7." << std::endl;
std::cout << "- verbose_flag is an integer between 0 and 3." << std::endl;
std::cout << "verbose_flag = 0 : minimal output (the benchmark times correspond to this flag)" << std::endl;
std::cout << "verbose_flag = 1 : output includes all closed sets + tests for classes of 2L polytopes" << std::endl;
std::cout << "verbose_flag = 2 : output includes all closed sets + H-embedding of ground set + tests for classes of 2L polytopes" << std::endl;
std::cout << "verbose_flag = 3 : output includes all closed sets, ground sets, slabs_sat_by_point and points_sat_by_slab + tests for classes of 2L polytopes" << std::endl << std::endl;
std::cout << "The input should be of the form ./2L_enum D verbose_flag, e.g.:" << std::endl;
std::cout << "./2L_enum 3 3" << std::endl;
std::cout << "which corresponds to D = 3 and verbose_flag = 3." << std::endl << std::endl;
return 1;
}
int D = atoi(argv[1]);
int verbose = atoi(argv[2]);
// Warnings and bound on D and verbose
if ((D != 1) && (D != 2) &&(D != 3) && (D != 4) && (D != 5) && (D != 6) && (D != 7)) {
std::cout << "\nERROR: Input (dimension D) out of bounds." << std::endl;
std::cout << "Please insert an integer value between 1 and 7 as dimension D." << std::endl;
std::cout << "The input should be of the form: ./2L_enum D verbose_flag." << std::endl << std::endl;
return 1;
}
if ((verbose != 0) && (verbose != 1) && (verbose != 2) && (verbose != 3)) {
std::cout << "\nERROR: Input (verbose_flag) out of bounds." << std::endl;
std::cout << "Please insert an integer value between 0 and 3 as verbose_flag." << std::endl;
std::cout << "verbose_flag = 0 : minimal output (the benchmark times correspond to this flag)" << std::endl;
std::cout << "verbose_flag = 1 : output includes all closed sets + tests for classes of 2L polytopes" << std::endl;
std::cout << "verbose_flag = 2 : output includes all closed sets + H-embedding of ground set + tests for classes of 2L polytopes" << std::endl;
std::cout << "verbose_flag = 3 : output includes all closed sets, ground sets, slabs_sat_by_point and points_sat_by_slab + tests for classes of 2L polytopes" << std::endl << std::endl;
std::cout << "The input should be of the form: ./2L_enum D verbose_flag." << std::endl << std::endl;
return 1;
}
if (D == 7) {
std::cout << "\nWARNING: the computation time for D = 7 is expected to take up to ~61 hours of computation time (on AMD Opteron(TM) 6134 2.3 GHz)." << std::endl;
std::cout << "Please insert 'y' to confirm: ";
char ch = getchar();
if((ch != 'y') && (ch != 'Y')) {
ungetc(ch, stdin);
return 1;
}
}
std::vector<std::vector<boost::dynamic_bitset<>>> atoms; // Vector with all the (D-1)-dim 2L-polytopes
std::vector<boost::dynamic_bitset<>> S; // A slack matrix of a (D-1)-dim polytope
boost::dynamic_bitset<> row; // Some row a slack matrix
std::string line;
// counters for number of 2-level polytopes
int total_2level = 0;
//int index = 0;
// counters for timers
std::chrono::time_point<std::chrono::system_clock> tot_start, tot_end;
std::chrono::time_point<std::chrono::system_clock> start_per_base, end_per_base;
std::chrono::time_point<std::chrono::system_clock> start_next_closure, end_next_closure;
std::chrono::time_point<std::chrono::system_clock> start_slack_matrix, end_slack_matrix;
std::chrono::time_point<std::chrono::system_clock> start_skip_test, end_skip_test;
std::chrono::time_point<std::chrono::system_clock> start_2level_test, end_2level_test;
double tot_next_closure = 0;
double tot_slack_matrix = 0;
double tot_2level_test = 0;
tot_start = std::chrono::system_clock::now();
std::cout << "\nWarning: in dynamic_bitsets, lowest index bits are written to the right!" << std::endl;
std::cout << "Reading all " << (D-1) << "-dimensional 2-level polytopes... ";
if (verbose != 0)
std::cout << std::endl;
// Open the file that contains (D-1)-dim 2L-polytopes
std::ifstream inputfile("./" + std::to_string(D-1) + "d.txt");
if (inputfile.is_open()) {
while (getline(inputfile,line)) {
// If we read some data
if (line.compare(std::string("-")) != 0) {
// Remove spaces
// string::iterator end_pos = std::remove(line.begin(),line.end(),' ');
// line.erase(end_pos, line.end());
// Turn the std::string into a set
row = (boost::dynamic_bitset<>)line;
if (verbose != 0)
std::cout << row << " (" << row.size() << ")" << std::endl;
S.push_back(row);
}
// Otherwise this is the end
else {
// Add the slack matrix to the list
atoms.push_back(S);
// Don't forget to clear S
S.clear();
if (verbose != 0)
std::cout << "-" << std::endl;
}
}
inputfile.close();
std::cout << "OK" << std::endl;
}
else {
std::cout << "Unable to open file." << std::endl;
return 1;
}
std::cout << "Number of polytopes read = " << atoms.size() << std::endl;
std::cout << "Computing canonical forms for all nonincidence graphs... ";
// Loop trough all the atoms, compute canonical form and store it
for (std::vector<std::vector<boost::dynamic_bitset<>>>::iterator it1=atoms.begin(); it1!=atoms.end(); ++it1)
atoms_cg.insert(std::pair<int,std::vector<setword>>(hash_matrix(*it1,D-1),canonicize(*it1)));
std::cout << "OK" << std::endl;
std::cout << "Processing bases..." << std::endl;
myfile.open(std::to_string(D) + "d.txt");
int N_closed_sets = 0;
// Main loop: loop through all the bases
for (std::vector<std::vector<boost::dynamic_bitset<>>>::iterator it1=atoms.begin(); it1!=atoms.end(); ++it1) {
start_per_base = std::chrono::system_clock::now();
std::vector<boost::dynamic_bitset<>> S = *it1;
int n_base = (int)distance(atoms.begin(),it1) +1;
std::cout << "\nBase #" << n_base << ':' << std::endl;
// Check if there is a simplicial core on the "top left" of the matrix
std::cout << "Simplicial core? ";
if (checksimplicialcore(S,D-1))
std::cout << "OK" << std::endl;
// Extract (extended) embedding transformation matrix M_d(0)
ublas::matrix<int> M = extractM(S,D);
if ((verbose==1) || (verbose==2) || (verbose == 3))
std::cout << "M_d(0) = " << M << std::endl;
// Compute inverse of matrix M_d(0)
ublas::matrix<int> Minv;
invertM(M,Minv);
if ((verbose==1) || (verbose==2) || (verbose == 3))
std::cout << "M_d(0)^{-1} = " << Minv << std::endl;
std::cout << "Constructing H-embedding of facets of the base... ";
// computing the facets of the base using the slack matrix S
std::vector<boost::dynamic_bitset<>> facets_base(S.size());
for (std::vector<boost::dynamic_bitset<>>::const_iterator it2 = S.begin(); it2 != S.end(); it2++) {
boost::dynamic_bitset<> E(D);
if ((*it2).test(D-1)) {
for (size_type i = 0; i < D-1; i++)
E[i+1] = !(*it2)[i];
}
else {
for (size_type i = 0; i < D-1; i++)
E[i+1] = (*it2)[i];
}
bool found = false;
for (std::vector<boost::dynamic_bitset<>>::iterator it3 = facets_base.begin(); it3 != facets_base.end() && !found; it3++)
found = ((*it3) == E);
if (!found) {
facets_base.push_back(E);
if (verbose == 3)
std::cout << E << ' ';
}
}
std::cout << "OK" << std::endl;
// Create the set Vert(P_0) (in V-embedding)
std::cout << "Building V-embedding of base... ";
std::vector<ublas::vector<int>> base_V;
// Loop through all vertices
for (int j=0; j<S[0].size(); j++) {
ublas::vector<int> point(D);
// Create a point whose first coordinate is 0, and the others are the D-1 first bits of the jth column of the slack matrix S
point[0] = 0;
for (int i=0; i<D-1; i++)
point[i+1] = (S[i])[j];
// Add point to the V-embedding of the ground set
base_V.push_back(point);
// Print point - for debugging
if (verbose==3)
std::cout << point << ' ';
}
std::cout << "OK" << std::endl;
std::cout << "Building V-embedding of the ground set... ";
std::vector<ublas::vector<int>> ground_set_V;
ublas::vector<int> count(D);
// initialize count to 0
for (int i=0; i<D; i++)
count(i) = 0;
bool carry;
// REDUCED GROUND SET
// Create the set of points in {1} x {-1,0,1}^{D-1} lex greater than e_1
// Its size is 1 + (3^{D-1} - 1)/2
ublas::vector<int> point(D);
point(0) = 1;
for (int i=1; i<D; i++)
point(i) = 0;
ground_set_V.push_back(point);
if (verbose == 3)
std::cout << point << ' ';
for (int i=D-1; i>0 ; i--) {
point(i) = 1;
count.clear();
while (count(D-1) == 0) {
int j;
// Extract a vector in {-1,0,1}^{D-i-1} to fill the vector
for (j=i+1; j<D; j++)
point(j) = count(j-1) - 1;
ground_set_V.push_back(point);
if (verbose == 2)
std::cout << point << ' ';
// Increase counter, by performing mod-3 computation
j = i;
do {
carry = (count(j) == 2);
count(j) = (count(j) + 1) % 3;
j++;
} while (carry && j < D);
}
}
std::cout << "OK" << std::endl;
// Create Vert(P_0) (H-embedding this time), the set of fixed points
std::cout << "Building H-embedding of base... ";
std::vector<ublas::vector<int>> base_H;
for (std::vector<ublas::vector<int>>::iterator it2=base_V.begin(); it2!=base_V.end(); it2++) {
ublas::vector<int> point(D);
point = prod(Minv,*it2);
base_H.push_back(point);
if (verbose == 3)