Added ZigzagPersistence::is_alive() + consistency zigzag outputs betti 1 at each stage
#ifndef __IMAGE_ZIGZAG_PERSISTENCE_H__
#define __IMAGE_ZIGZAG_PERSISTENCE_H__
#include "zigzag-persistence.h"
#include <limits>
struct SimplexSubcomplexData
{
SimplexSubcomplexData(bool sc = false):
subcomplex(sc) {}
bool subcomplex;
};
template<class BirthID_ = Empty<> >
class ImageZigzagPersistence: public ZigzagPersistence<BirthID_, SimplexSubcomplexData>
{
public:
typedef BirthID_ BirthID;
typedef ZigzagPersistence<BirthID, SimplexSubcomplexData> Parent;
typedef typename Parent::IndexDeathPair IndexDeathPair;
typedef typename Parent::Death Death;
typedef typename Parent::ZIndex ZIndex;
typedef typename Parent::BIndex BIndex;
typedef typename Parent::SimplexIndex SimplexIndex;
typedef typename Parent::ZColumn ZColumn;
typedef typename Parent::BColumn BColumn;
typedef typename Parent::BRow BRow;
typedef typename Parent::CRow CRow;
typedef typename Parent::ZNode ZNode;
typedef typename Parent::BNode BNode;
typedef typename Parent::SimplexNode SimplexNode;
ImageZigzagPersistence():
im_last(Parent::z_list.end()), cok_begin(Parent::z_list.end()),
im_order_begin(std::numeric_limits<int>::min()/2),
cok_order_begin(std::numeric_limits<int>::max()/2)
{}
IndexDeathPair add(ZColumn bdry,
bool subcomplex,
const BirthID& birth = BirthID()) { ImageZZVisitor zzv(subcomplex); return Parent::add(bdry, birth, zzv); }
Death remove(SimplexIndex s, const BirthID& birth = BirthID()) { ImageZZVisitor zzv(s->subcomplex); return Parent::remove(s, birth, zzv); }
ZIndex image_begin() { return Parent::z_list.begin(); }
ZIndex image_end() { return cok_begin; }
BIndex boundary_end() { return Parent::b_list.end(); }
// Class: ImageZZVisitor
// Contains all the tweaks to the normal zigzag algorithm to make it compute image zigzag
class ImageZZVisitor: public Parent::ZigzagVisitor
{
public:
ImageZZVisitor(bool sc = false):
subcomplex(sc), birth_in_image(false) {}
// Sets the subcomplex property of the new simplex
SimplexIndex new_simplex(Parent& zz);
// Decides where to put the new column (image or cokernel)
ZIndex new_z_in_add(Parent& zz, const ZColumn& z, const BRow& u);
// Checks if there is a boundary entirely in the subcomplex, and sets birth_in_image accordingly
BIndex select_j_in_remove(Parent& zz, const CRow& c_row);
ZIndex new_z_in_remove(Parent& zz);
// Updates im_last and cok_begin if necessary
void erasing_z(Parent& zz, ZIndex j);
// Determines if there is a death in the image
Death death(Parent& zz, ZIndex dying_z);
private:
ZIndex append_in_image(Parent& zz);
ZIndex append_in_cokernel(Parent& zz);
ZIndex prepend_in_image(Parent& zz);
ZIndex prepend_in_cokernel(Parent& zz);
bool in_subcomplex(const ZColumn& z);
bool subcomplex, birth_in_image;
};
const int im_order_begin;
const int cok_order_begin;
private:
using Parent::make_remover;
using Parent::make_appender;
using Parent::make_adder;
private:
ZIndex im_last; // index of the last image cycle
ZIndex cok_begin; // index of the first cokernel cycle
};
#include "image-zigzag-persistence.hpp"
#endif