def d2yxu(self, i, j):
'''Return distance squared, points[i] to -[j] deltas and
longitudinal unrollment.
'''
p1 = self.pts[i]
p2 = self.pts[j]
return equirectangular_(p1.lat, p1.lon, p2.lat, p2.lon, **self.options)
def distance2To(self, other, radius=R_M, adjust=False, wrap=False):
'''Compute the distance between this and an other geohash
using the U{Equirectangular Approximation / Projection
<http://www.Movable-Type.co.UK/scripts/latlong.html>}.
@param other: The other geohash (L{Geohash}).
@keyword radius: Optional, mean earth radius (C{meter}) or
C{None}.
@keyword adjust: Adjust the wrapped, unrolled longitudinal
delta by the cosine of the mean latitude
(C{bool}).
@keyword wrap: Wrap and unroll longitudes (C{bool}).
@return: Approximate distance (C{meter}, same units as I{radius})
or distance squared (C{degrees} squared) if I{radius}
is C{None} or 0.
@raise TypeError: The I{other} is not a L{Geohash}, C{LatLon}
or C{str}.
@see: U{Local, flat earth approximation
<http://www.EdWilliams.org/avform.htm#flat>}, functions
'''
other = _2Geohash(other)
a1, b1 = self.latlon
a2, b2 = other.latlon
if radius:
return equirectangular(a1, b1, a2, b2, radius=radius,
adjust=adjust, limit=None, wrap=wrap)
else:
return equirectangular_(a1, b1, a2, b2,
adjust=adjust, limit=None, wrap=wrap)[0]
def equirectangular3(lat1, lon1, lat2, lon2, **options):
'''DEPRECATED, use function C{equirectangular_}.
@return: 3-Tuple C{(distance2, delta_lat, delta_lon)}.
'''
from formy import equirectangular_
return tuple(equirectangular_(lat1, lon1, lat2, lon2, **options)[:3])
def _d2yx(p2, p1, u, i):
w = wrap if (not closed or i < (n - 1)) else False
# equirectangular_ returns a 4-tuple (distance in
# degrees squared, delta lat, delta lon, p2.lon
# unroll/wrap); the previous p2.lon unroll/wrap
# is also applied to the next edge's p1.lon
return equirectangular_(p1.lat, p1.lon + u,
p2.lat, p2.lon, wrap=w, **options)
def _degs(n, pts, closed): # angular edge lengths in degrees
i, m = _imdex2(closed, n)
x1, y1, _ = pts[i]
u = 0 # previous x2's unroll/wrap
for i in range(m, n):
x2, y2, _ = pts[i]
w = wrap if (not closed or i < (n - 1)) else False
# apply previous x2's unroll/wrap to new x1
_, dy, dx, u = equirectangular_(y1, x1 + u, y2, x2,
adjust=adjust,
limit=None,
wrap=w)
yield hypot(dx, dy)
x1, y1 = x2, y2
def equirectangular3(lat1, lon1, lat2, lon2, **options):
'''DEPRECATED, use function I{equirectangular_}.
@return: 3-Tuple (distance2, delta_lat, delta_lon).
'''
return formy.equirectangular_(lat1, lon1, lat2, lon2, **options)[:3]