def _intersects2(c1, rad1, c2, rad2, radius=R_M, # in .ellipsoidalBase._intersects2
height=None, wrap=True, too_d=None,
LatLon=LatLon, **LatLon_kwds):
# (INTERNAL) Intersect two spherical circles, see L{intersections2}
# above, separated to allow callers to embellish any exceptions
def _dest3(bearing, h):
a, b = _destination2(a1, b1, r1, bearing)
return _latlon3(degrees90(a), degrees180(b), h,
intersections2, LatLon, **LatLon_kwds)
r1, r2, f = _rads3(rad1, rad2, radius)
if f: # swapped
c1, c2 = c2, c1 # PYCHOK swap
a1, b1 = c1.philam
a2, b2 = c2.philam
db, b2 = unrollPI(b1, b2, wrap=wrap)
d = vincentys_(a2, a1, db) # radians
if d < max(r1 - r2, EPS):
raise ValueError(_near_concentric_)
x = fsum_(r1, r2, -d) # overlap
if x > EPS:
sd, cd, sr1, cr1, _, cr2 = sincos2(d, r1, r2)
x = sd * sr1
if abs(x) < EPS:
raise ValueError(_invalid_)
x = acos1((cr2 - cd * cr1) / x) # 0 <= x <= PI
elif x < 0:
t = (d * radius) if too_d is None else too_d
raise ValueError(_too_distant_fmt_ % (t,))
if height is None: # "radical height"
f = _radical2(d, r1, r2).ratio
h = Height(favg(c1.height, c2.height, f=f))
else:
h = Height(height)
b = bearing_(a1, b1, a2, b2, final=False, wrap=wrap)
if x < _EPS_I2: # externally ...
r = _dest3(b, h)
elif x > _PI_EPS_I2: # internally ...
r = _dest3(b + PI, h)
else:
return _dest3(b + x, h), _dest3(b - x, h)
return r, r # ... abutting circles
def initialBearingTo(self, other, wrap=False, raiser=False):
'''Compute the initial bearing (forward azimuth) from this
to an other point.
@param other: The other point (spherical L{LatLon}).
@keyword wrap: Wrap and unroll longitudes (C{bool}).
@keyword raiser: Optionally, raise L{CrossError} (C{bool}),
use B{C{raiser}}=C{True} for behavior like
C{sphericalNvector.LatLon.initialBearingTo}.
@return: Initial bearing (compass C{degrees360}).
@raise CrossError: If this and the B{C{other}} point coincide,
provided B{C{raiser}} is C{True} and
L{crosserrors} is C{True}.
@raise TypeError: The B{C{other}} point is not L{LatLon}.
@example:
>>> p1 = LatLon(52.205, 0.119)
>>> p2 = LatLon(48.857, 2.351)
>>> b = p1.initialBearingTo(p2) # 156.2
@JSname: I{bearingTo}.
'''
self.others(other)
a1, b1 = self.to2ab()
a2, b2 = other.to2ab()
# XXX behavior like sphericalNvector.LatLon.initialBearingTo
if raiser and crosserrors() and max(abs(a2 - a1), abs(b2 - b1)) < EPS:
raise CrossError('%s %s: %r' % ('coincident', 'points', other))
return degrees(bearing_(a1, b1, a2, b2, final=False, wrap=wrap))
def _xb(a1, b1, end, a, b, wrap):
# difference between the bearing to (a, b) and the given
# bearing is negative if both are in opposite directions
r = bearing_(a1, b1, radians(a), radians(b), wrap=wrap)
return PI_2 - abs(wrapPI(r - radians(end)))
def intersections2(
center1,
rad1,
center2,
rad2,
radius=R_M, # MCCABE 13
height=None,
wrap=False,
LatLon=LatLon,
**LatLon_kwds):
'''Compute the intersection points of two circles each defined
by a center point and radius.
@arg center1: Center of the first circle (L{LatLon}).
@arg rad1: Radius of the second circle (C{meter} or C{radians},
see B{C{radius}}).
@arg center2: Center of the second circle (L{LatLon}).
@arg rad2: Radius of the second circle (C{meter} or C{radians},
see B{C{radius}}).
@kwarg radius: Mean earth radius (C{meter} or C{None} if both
B{C{rad1}} and B{C{rad2}} are given in C{radians}).
@kwarg height: Optional height for the intersection point,
overriding the mean height (C{meter}).
@kwarg wrap: Wrap and unroll longitudes (C{bool}).
@kwarg LatLon: Optional class to return the intersection
points (L{LatLon}) or C{None}.
@kwarg LatLon_kwds: Optional, additional B{C{LatLon}} keyword
arguments, ignored if B{C{LatLon=None}}.
@return: 2-Tuple of the intersection points, each a B{C{LatLon}}
instance or L{LatLon3Tuple}C{(lat, lon, height)} if
B{C{LatLon}} is C{None}. The intersection points are
the same instance for abutting circles.
@raise IntersectionError: Concentric, antipodal, invalid or
non-intersecting circles.
@raise TypeError: If B{C{center1}} or B{C{center2}} not L{LatLon}.
@raise ValueError: Invalid B{C{rad1}}, B{C{rad2}}, B{C{radius}} or
B{C{height}}.
@note: Courtesy U{Samuel Čavoj<https://GitHub.com/mrJean1/PyGeodesy/issues/41>}.
@see: This U{Answer<https://StackOverflow.com/questions/53324667/
find-intersection-coordinates-of-two-circles-on-earth/53331953>}.
'''
def _destination1(bearing):
a, b = _destination2(a1, b1, r1, bearing)
return _latlon3(degrees90(a), degrees180(b), h, intersections2, LatLon,
**LatLon_kwds)
_Trll.others(center1, name='center1')
_Trll.others(center2, name='center2')
a1, b1 = center1.philam
a2, b2 = center2.philam
r1, r2, x = _rads3(rad1, rad2, radius)
if x:
a1, b1, a2, b2 = a2, b2, a1, b1
db, _ = unrollPI(b1, b2, wrap=wrap)
d = vincentys_(a2, a1, db) # radians
if d < max(r1 - r2, EPS):
raise IntersectionError(center1=center1,
rad1=rad1,
center2=center2,
rad2=rad2,
txt=_near_concentric_)
x = fsum_(r1, r2, -d)
if x > EPS:
try:
sd, cd, s1, c1, _, c2 = sincos2(d, r1, r2)
x = sd * s1
if abs(x) < EPS:
raise ValueError
x = acos1((c2 - cd * c1) / x)
except ValueError:
raise IntersectionError(center1=center1,
rad1=rad1,
center2=center2,
rad2=rad2)
elif x < 0:
raise IntersectionError(center1=center1,
rad1=rad1,
center2=center2,
rad2=rad2,
txt=_too_distant_)
b = bearing_(a1, b1, a2, b2, final=False, wrap=wrap)
if height is None:
h = fmean((center1.height, center2.height))
else:
Height(height)
if abs(x) > EPS:
return _destination1(b + x), _destination1(b - x)
else: # abutting circles
x = _destination1(b)
return x, x
