Source code for oineus.diff.mapping_cylinder

import numpy as np
import eagerpy as epy

from .. import _oineus
from .diff_filtration import DiffFiltration



[docs]
def mapping_cylinder_filtration(fil_domain: DiffFiltration, fil_codomain: DiffFiltration,
                                v_domain, v_codomain,
                                v_domain_value=None, v_codomain_value=None) -> DiffFiltration:
    assert type(fil_domain) is DiffFiltration
    assert type(fil_codomain) is DiffFiltration

    if isinstance(v_domain, _oineus.Simplex):
        v_domain = v_domain.combinatorial_cell

    if isinstance(v_codomain, _oineus.Simplex):
        v_codomain = v_codomain.combinatorial_cell

    under_fil_dom = fil_domain.under_fil
    under_fil_cod = fil_codomain.under_fil

    if v_domain_value is None:
        v_domain_value = under_fil_dom.neg_infinity()
    if v_codomain_value is None:
        v_codomain_value = under_fil_cod.neg_infinity()

    under_cyl_fil, cyl_val_inds = _oineus._mapping_cylinder_with_indices(
        under_fil_dom, under_fil_cod, v_domain, v_codomain, v_domain_value, v_codomain_value
    )

    cyl_val_inds = epy.astensor(np.array(cyl_val_inds, dtype=np.int64))
    concat_vals = epy.concatenate((epy.astensor(fil_domain.values), epy.astensor(fil_codomain.values)))

    assert concat_vals.ndim == 1 and concat_vals.shape[0] == fil_domain.size() + fil_codomain.size()

    cyl_values = concat_vals[cyl_val_inds].raw

    under_cyl_fil.kind = _oineus.FiltrationKind.MappingCylinder
    return DiffFiltration(under_cyl_fil, cyl_values)