def discrete(self, points, fraction=None):
'''Compute the C{forward, discrete Fréchet} distance.
@param points: Second set of points (C{LatLon}[], C{Numpy2LatLon}[],
C{Tuple2LatLon}[] or C{other}[]).
@keyword fraction: Index fraction (C{float} in L{EPS}..L{EPS1}) to
interpolate intermediate B{C{points}} or C{None}
or C{1} for no intermediate B{C{points}} and no
I{fractional} indices.
@return: A L{Frechet6Tuple}C{(fd, fi1, fi2, r, n, units)}.
@raise FrechetError: Insufficient number of B{C{points}} or
invalid B{C{fraction}}.
@raise RecursionError: Recursion depth exceeded, see U{sys.getrecursionlimit()
<https://docs.Python.org/3/library/sys.html#sys.getrecursionlimit>}.
'''
n2, ps2 = _points2(points, closed=False, Error=FrechetError)
f2 = _fraction(fraction, n2)
p2 = self.points_fraction if f2 < EPS1 else self.points_ # PYCHOK expected
f1 = self.fraction
p1 = self.points_fraction if f1 < EPS1 else self.points_ # PYCHOK expected
def dF(fi1, fi2):
return self.distance(p1(self._ps1, fi1), p2(ps2, fi2))
return _frechet_(self._n1, f1, n2, f2, dF, self.units)
def __init__(self, points, fraction=None, name='', units='', **wrap_adjust):
'''New C{Frechet...} calculator/interpolator.
@arg points: First set of points (C{LatLon}[], L{Numpy2LatLon}[],
L{Tuple2LatLon}[] or C{other}[]).
@kwarg fraction: Index fraction (C{float} in L{EPS}..L{EPS1}) to
interpolate intermediate B{C{points}} or use
C{None}, C{0} or C{1} for no intermediate
B{C{points}} and no I{fractional} indices.
@kwarg name: Optional calculator/interpolator name (C{str}).
@kwarg units: Optional distance units (C{str}).
@kwarg wrap_adjust: Optionally, C{wrap} and unroll longitudes, iff
applicable (C{bool}) and C{adjust} wrapped,
unrolled longitudinal delta by the cosine
of the mean latitude, iff applicable.
@raise FrechetError: Insufficient number of B{C{points}} or
invalid B{C{fraction}} or B{{wrap}} or
B{C{ajust}} not applicable.
'''
self._n1, self._ps1 = _points2(points, closed=False, Error=FrechetError)
if fraction:
self.fraction = fraction
if name:
self.name = name
if units and not self.units:
self.units = units
if wrap_adjust:
_bkwds(self, Error=FrechetError, **wrap_adjust)
def frechet_(points1, points2, distance=None, units=''):
'''Compute the I{discrete} U{Fréchet<https://WikiPedia.org/wiki/Frechet_distance>}
distance between two paths given as sets of points.
@param points1: First set of points (C{LatLon}[], C{Numpy2LatLon}[],
C{Tuple2LatLon}[] or C{other}[]).
@param points2: Second set of points (C{LatLon}[], C{Numpy2LatLon}[],
C{Tuple2LatLon}[] or C{other}[]).
@keyword distance: Callable returning the distance between a B{C{points1}}
and a B{C{points2}} point (signature C{(point1, point2)}).
@keyword units: Optional, name of the distance units (C{str}).
@return: A L{Frechet6Tuple}C{(fd, fi1, fi2, r, n, units)} where C{fi1} and
C{fi2} are type C{int} indices into B{C{points1}} respectively
B{C{points2}}.
@raise FrechetError: Insufficient number of B{C{points1}} or B{C{points2}}.
@raise RecursionError: Recursion depth exceeded, see U{sys.getrecursionlimit()
<https://docs.Python.org/3/library/sys.html#sys.getrecursionlimit>}.
@raise TypeError: If B{C{distance}} is not a callable.
@note: Keyword C{fraction}, intermediate B{C{points1}} and B{C{points2}}
and I{fractional} indices are I{not} supported in this L{frechet_}
function.
'''
if not callable(distance):
raise _IsNotError(callable.__name__, distance=distance)
n1, ps1 = _points2(points1, closed=False, Error=FrechetError)
n2, ps2 = _points2(points2, closed=False, Error=FrechetError)
def dF(i1, i2):
return distance(ps1[i1], ps2[i2])
return _frechet_(n1, 1, n2, 1, dF, units)
def __init__(self, points, fraction=None, name='', units=''):
'''New L{Frechet} calculator/interpolator.
@param points: First set of points (C{LatLon}[], C{Numpy2LatLon}[],
C{Tuple2LatLon}[] or C{other}[]).
@keyword fraction: Index fraction (C{float} in L{EPS}..L{EPS1}) to
interpolate intermediate B{C{points}} or C{None}
or C{1} for no intermediate B{C{points}} and no
I{fractional} indices.
@keyword name: Optional calculator/interpolator name (C{str}).
@keyword units: Optional, distance units (C{str}).
@raise FrechetError: Insufficient number of B{C{points}} or
invalid B{C{fraction}}.
'''
self._n1, self._ps1 = _points2(points, closed=False, Error=FrechetError)
if fraction:
self.fraction = fraction
if name:
self.name = name
if units:
self.units = units
def _points2(self, points):
'''(INTERNAL) Check a set of points.
'''
return _points2(points, closed=False, Error=FrechetError)