Coverage for pygeodesy/geodesicx/gxbases.py: 92%
53 statements
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« prev ^ index » next coverage.py v7.2.2, created at 2023-12-29 12:35 -0500
2# -*- coding: utf-8 -*-
4u'''(INTERNAL) Private L{geodesicx} base class, functions and constants.
6Copyright (C) U{Charles Karney<mailto:Karney@Alum.MIT.edu>} (2008-2023)
7and licensed under the MIT/X11 License. For more information, see the
8U{GeographicLib<https://GeographicLib.SourceForge.io>} documentation.
9'''
11# from pygeodesy.basics import isodd # from .karney
12from pygeodesy.constants import _0_0, _100_0
13from pygeodesy.errors import _not_, _or
14# from pygeodesy.fmath import hypot as _hypot # from .karney
15# from pygeodesy.interns import _not_ # from .errors
16from pygeodesy.karney import _CapsBase, GeodesicError, isodd, \
17 _2cos2x, _hypot, _sum2_, _MODS
18# from pygeodesy.lazily import printf # _MODS
20from math import ldexp as _ldexp
22__all__ = ()
23__version__ = '23.11.18'
25# valid C{nC4}s and C{C4order}s, see _xnC4 below
26_nC4s = {24: 2900, 27: 4032, 30: 5425}
29class _GeodesicBase(_CapsBase): # in .geodsolve
30 '''(INTERNAL) Base class for C{[_]Geodesic*Exact}.
31 '''
32# def toRepr(self, prec=6, sep=_COMMASPACE_, **unused): # PYCHOK signature
33# '''Return this C{GeodesicExact*} items string.
34#
35# @kwarg prec: The C{float} precision, number of decimal digits (0..9).
36# Trailing zero decimals are stripped for B{C{prec}} values
37# of 1 and above, but kept for negative B{C{prec}} values.
38# @kwarg sep: Separator to join (C{str}).
39#
40# @return: C{GeodesicExact*} (C{str}).
41# '''
42# return Fmt.PAREN(self.named, self.toStr(prec=prec, sep=sep))
43 pass
46class _Gfloats(dict):
47 '''(INTERNAL) Uniquify floats.
48 '''
49 n = 0 # total number of floats
50 nC4 = 0
52 def __init__(self, nC4): # PYCHOK signature
53 self.nC4 = nC4
55 def __call__(self, fs):
56 '''Return a tuple of "uniquified" floats.
57 '''
58 self.n += len(fs)
59 _f = self.setdefault
60 return tuple(_f(f, f) for f in map(float, fs)) # PYCHOK as attr
62 def prints(self):
63 n, u = self.n, len(self.keys())
64 d = (n - u) * _100_0 / n
65 _MODS.lazily.printf('_CX_%d: n=%d, u=%d, d=%.1f%%', self.nC4, n, u, d) # XXX
68def _cosSeries(c4s, sx, cx): # PYCHOK shared .geodesicx.gx and -.gxline
69 '''(INTERNAL) I{Karney}'s cosine series expansion using U{Clenshaw
70 summation<https://WikiPedia.org/wiki/Clenshaw_algorithm>}.
71 '''
72 ar = _2cos2x(cx, sx)
73 y0 = t0 = y1 = t1 = _0_0
74 c4 = list(c4s)
75 _c4 = c4.pop
76 _s2 = _sum2_
77 if isodd(len(c4)):
78 y0 = _c4()
79 while c4:
80 # y1 = ar * y0 - y1 + c4.pop()
81 # y0 = ar * y1 - y0 + c4.pop()
82 y1, t1 = _s2(ar * y0, ar * t0, -y1, -t1, _c4())
83 y0, t0 = _s2(ar * y1, ar * t1, -y0, -t0, _c4())
84 # s = cx * (y0 - y1)
85 s, _ = _s2(cx * y0, _0_0, cx * t0, -cx * y1, -cx * t1)
86 return s
89_f = float # in _f2 and .geodesicx._C4_24, _27 and _30
92def _f2(hi, lo): # in .geodesicx._C4_24, _27 and _30
93 '''(INTERNAL) For C{_coeffs}.
94 '''
95 return _ldexp(_f(hi), 52) + _f(lo)
98def _sincos12(sin1, cos1, sin2, cos2, sineg0=False): # PYCHOK shared
99 '''(INTERNAL) Compute the sine and cosine of angle
100 M{ang12 = atan2(sin2, cos2) - atan2(sin1, cos1)}.
102 Negate C{sin1} to get C{sin12} and C{cos12} of the sum
103 M{ang12 = atan2(sin2, cos2) + atan2(sin1, cos1)}.
105 @kwarg sineg0: If C{True}, make negative C{sin12} zero (C{bool}).
107 @return: 2-Tuple C{(sin12, cos12)}.
108 '''
109 s = sin2 * cos1 - sin1 * cos2
110 c = cos2 * cos1 + sin1 * sin2
111 if sineg0 and s < 0:
112 s = _0_0 # max(s, _0_0) or NEG0?
113 return s, c
116def _sin1cos2(sin1, cos1, sin2, cos2): # PYCHOK shared
117 '''(INTERNAL) Compute the C{sin1 * cos2} sine and its cosine.
119 @return: 2-Tuple C{(sin1 * cos2, hypot(sin1 * sin2, cos1)}.
120 '''
121 s = sin1 * cos2
122 c = _hypot(sin1 * sin2, cos1)
123 return s, c # _norm2(s, c)
126def _xnC4(**name_nC4):
127 '''(INTERNAL) Validate C{C4order}.
128 '''
129 n, nC4 = name_nC4.popitem()
130 if nC4 not in _nC4s or not isinstance(nC4, int):
131 raise GeodesicError(n, nC4, txt=_not_(_or(*map(str, _nC4s))))
132 return _nC4s[nC4]
135# **) MIT License
136#
137# Copyright (C) 2016-2024 -- mrJean1 at Gmail -- All Rights Reserved.
138#
139# Permission is hereby granted, free of charge, to any person obtaining a
140# copy of this software and associated documentation files (the "Software"),
141# to deal in the Software without restriction, including without limitation
142# the rights to use, copy, modify, merge, publish, distribute, sublicense,
143# and/or sell copies of the Software, and to permit persons to whom the
144# Software is furnished to do so, subject to the following conditions:
145#
146# The above copyright notice and this permission notice shall be included
147# in all copies or substantial portions of the Software.
148#
149# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
150# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
151# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
152# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
153# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
154# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
155# OTHER DEALINGS IN THE SOFTWARE.