diff options
Diffstat (limited to 'src/python/gudhi/alpha_complex.pyx')
| -rw-r--r-- | src/python/gudhi/alpha_complex.pyx | 91 |
1 files changed, 63 insertions, 28 deletions
diff --git a/src/python/gudhi/alpha_complex.pyx b/src/python/gudhi/alpha_complex.pyx index ea128743..375e1561 100644 --- a/src/python/gudhi/alpha_complex.pyx +++ b/src/python/gudhi/alpha_complex.pyx @@ -16,7 +16,7 @@ from libcpp.utility cimport pair from libcpp.string cimport string from libcpp cimport bool from libc.stdint cimport intptr_t -import os +import warnings from gudhi.simplex_tree cimport * from gudhi.simplex_tree import SimplexTree @@ -28,66 +28,76 @@ __license__ = "GPL v3" cdef extern from "Alpha_complex_interface.h" namespace "Gudhi": cdef cppclass Alpha_complex_interface "Gudhi::alpha_complex::Alpha_complex_interface": - Alpha_complex_interface(vector[vector[double]] points, bool fast_version, bool exact_version) nogil except + + Alpha_complex_interface(vector[vector[double]] points, vector[double] weights, bool fast_version, bool exact_version) nogil except + vector[double] get_point(int vertex) nogil except + void create_simplex_tree(Simplex_tree_interface_full_featured* simplex_tree, double max_alpha_square, bool default_filtration_value) nogil except + + @staticmethod + void set_float_relative_precision(double precision) nogil + @staticmethod + double get_float_relative_precision() nogil # AlphaComplex python interface cdef class AlphaComplex: - """AlphaComplex is a simplicial complex constructed from the finite cells - of a Delaunay Triangulation. + """AlphaComplex is a simplicial complex constructed from the finite cells of a Delaunay Triangulation. - The filtration value of each simplex is computed as the square of the - circumradius of the simplex if the circumsphere is empty (the simplex is - then said to be Gabriel), and as the minimum of the filtration values of - the codimension 1 cofaces that make it not Gabriel otherwise. + The filtration value of each simplex is computed as the square of the circumradius of the simplex if the + circumsphere is empty (the simplex is then said to be Gabriel), and as the minimum of the filtration values of the + codimension 1 cofaces that make it not Gabriel otherwise. - All simplices that have a filtration value strictly greater than a given - alpha squared value are not inserted into the complex. + All simplices that have a filtration value strictly greater than a given alpha squared value are not inserted into + the complex. .. note:: - When Alpha_complex is constructed with an infinite value of alpha, the - complex is a Delaunay complex. - + When Alpha_complex is constructed with an infinite value of alpha, the complex is a Delaunay complex. """ cdef Alpha_complex_interface * this_ptr # Fake constructor that does nothing but documenting the constructor - def __init__(self, points=None, off_file='', precision='safe'): + def __init__(self, points=[], off_file='', weights=None, precision='safe'): """AlphaComplex constructor. :param points: A list of points in d-Dimension. - :type points: list of list of double - - Or + :type points: Iterable[Iterable[float]] - :param off_file: An OFF file style name. + :param off_file: **[deprecated]** An `OFF file style <fileformats.html#off-file-format>`_ name. + If an `off_file` is given with `points` as arguments, only points from the file are taken into account. :type off_file: string + :param weights: A list of weights. If set, the number of weights must correspond to the number of points. + :type weights: Iterable[float] + :param precision: Alpha complex precision can be 'fast', 'safe' or 'exact'. Default is 'safe'. :type precision: string + + :raises FileNotFoundError: **[deprecated]** If `off_file` is set but not found. + :raises ValueError: In case of inconsistency between the number of points and weights. """ # The real cython constructor - def __cinit__(self, points = None, off_file = '', precision = 'safe'): + def __cinit__(self, points = [], off_file = '', weights=None, precision = 'safe'): assert precision in ['fast', 'safe', 'exact'], "Alpha complex precision can only be 'fast', 'safe' or 'exact'" cdef bool fast = precision == 'fast' cdef bool exact = precision == 'exact' - cdef vector[vector[double]] pts if off_file: - if os.path.isfile(off_file): - points = read_points_from_off_file(off_file = off_file) - else: - print("file " + off_file + " not found.") - if points is None: - # Empty Alpha construction - points=[] + warnings.warn("off_file is a deprecated parameter, please consider using gudhi.read_points_from_off_file", + DeprecationWarning) + points = read_points_from_off_file(off_file = off_file) + + # weights are set but is inconsistent with the number of points + if weights != None and len(weights) != len(points): + raise ValueError("Inconsistency between the number of points and weights") + + # need to copy the points to use them without the gil + cdef vector[vector[double]] pts + cdef vector[double] wgts pts = points + if weights != None: + wgts = weights with nogil: - self.this_ptr = new Alpha_complex_interface(pts, fast, exact) + self.this_ptr = new Alpha_complex_interface(pts, wgts, fast, exact) def __dealloc__(self): if self.this_ptr != NULL: @@ -127,3 +137,28 @@ cdef class AlphaComplex: self.this_ptr.create_simplex_tree(<Simplex_tree_interface_full_featured*>stree_int_ptr, mas, compute_filtration) return stree + + @staticmethod + def set_float_relative_precision(precision): + """ + :param precision: When the AlphaComplex is constructed with :code:`precision = 'safe'` (the default), + one can set the float relative precision of filtration values computed in + :func:`~gudhi.AlphaComplex.create_simplex_tree`. + Default is :code:`1e-5` (cf. :func:`~gudhi.AlphaComplex.get_float_relative_precision`). + For more details, please refer to + `CGAL::Lazy_exact_nt<NT>::set_relative_precision_of_to_double <https://doc.cgal.org/latest/Number_types/classCGAL_1_1Lazy__exact__nt.html>`_ + :type precision: float + """ + if precision <=0. or precision >= 1.: + raise ValueError("Relative precision value must be strictly greater than 0 and strictly lower than 1") + Alpha_complex_interface.set_float_relative_precision(precision) + + @staticmethod + def get_float_relative_precision(): + """ + :returns: The float relative precision of filtration values computation in + :func:`~gudhi.AlphaComplex.create_simplex_tree` when the AlphaComplex is constructed with + :code:`precision = 'safe'` (the default). + :rtype: float + """ + return Alpha_complex_interface.get_float_relative_precision() |