Coverage for pygeodesy/geodesicx/gxbases.py: 93%
55 statements
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« prev ^ index » next coverage.py v7.2.2, created at 2024-06-10 14:08 -0400
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'''
11from pygeodesy.basics import isodd, _MODS
12from pygeodesy.constants import _0_0, _100_0
13from pygeodesy.errors import _or, _xkwds_item2
14from pygeodesy.fmath import hypot as _hypot
15from pygeodesy.karney import _CapsBase, GeodesicError, _2cos2x, _sum2_
16# from pygeodesy.lazily import _MODS, printf # .basics, _MODS
18from math import ldexp as _ldexp
20__all__ = ()
21__version__ = '24.05.19'
23# valid C{nC4}s and C{C4order}s, see _xnC4 below
24_nC4s = {24: 2900, 27: 4032, 30: 5425}
27class _GeodesicBase(_CapsBase): # in .geodsolve
28 '''(INTERNAL) Base class for C{[_]Geodesic*Exact}.
29 '''
30# def toRepr(self, prec=6, sep=_COMMASPACE_, **unused): # PYCHOK signature
31# '''Return this C{GeodesicExact*} items string.
32#
33# @kwarg prec: The C{float} precision, number of decimal digits (0..9).
34# Trailing zero decimals are stripped for B{C{prec}} values
35# of 1 and above, but kept for negative B{C{prec}} values.
36# @kwarg sep: Separator to join (C{str}).
37#
38# @return: C{GeodesicExact*} (C{str}).
39# '''
40# return Fmt.PAREN(self.named, self.toStr(prec=prec, sep=sep))
41 pass
44class _Gfloats(dict):
45 '''(INTERNAL) Uniquify floats.
46 '''
47 n = 0 # total number of floats
48 nC4 = 0
50 def __init__(self, nC4): # PYCHOK signature
51 self.nC4 = nC4
53 def __call__(self, fs):
54 '''Return a tuple of "uniquified" floats.
55 '''
56 self.n += len(fs)
57 _f = self.setdefault
58 return tuple(_f(f, f) for f in map(float, fs)) # PYCHOK as attr
60 def prints(self):
61 n, u = self.n, len(self.keys())
62 d = (n - u) * _100_0 / n
63 _MODS.lazily.printf('_CX_%d: n=%d, u=%d, d=%.1f%%', self.nC4, n, u, d) # XXX
66def _cosSeries(c4s, sx, cx): # PYCHOK shared .geodesicx.gx and -.gxline
67 '''(INTERNAL) I{Karney}'s cosine series expansion using U{Clenshaw
68 summation<https://WikiPedia.org/wiki/Clenshaw_algorithm>}.
69 '''
70 ar = _2cos2x(cx, sx)
71 y0 = t0 = y1 = t1 = _0_0
72 c4 = list(c4s)
73 _c4 = c4.pop
74 _s2 = _sum2_
75 if isodd(len(c4)):
76 y0 = _c4()
77 while c4:
78 # y1 = ar * y0 - y1 + c4.pop()
79 # y0 = ar * y1 - y0 + c4.pop()
80 y1, t1 = _s2(ar * y0, ar * t0, -y1, -t1, _c4())
81 y0, t0 = _s2(ar * y1, ar * t1, -y0, -t0, _c4())
82 # s = cx * (y0 - y1)
83 s, _ = _s2(cx * y0, _0_0, cx * t0, -cx * y1, -cx * t1)
84 return s
87_f = float # in _f2 and .geodesicx._C4_24, _27 and _30
90def _f2(hi, lo): # in .geodesicx._C4_24, _27 and _30
91 '''(INTERNAL) For C{_coeffs}.
92 '''
93 return _ldexp(_f(hi), 52) + _f(lo)
96def _sincos12(sin1, cos1, sin2, cos2, sineg0=False): # PYCHOK shared
97 '''(INTERNAL) Compute the sine and cosine of angle
98 M{ang12 = atan2(sin2, cos2) - atan2(sin1, cos1)}.
100 Negate C{sin1} to get C{sin12} and C{cos12} of the sum
101 M{ang12 = atan2(sin2, cos2) + atan2(sin1, cos1)}.
103 @kwarg sineg0: If C{True}, make negative C{sin12} zero (C{bool}).
105 @return: 2-Tuple C{(sin12, cos12)}.
106 '''
107 s = sin2 * cos1 - sin1 * cos2
108 c = cos2 * cos1 + sin1 * sin2
109 if sineg0 and s < 0:
110 s = _0_0 # max(s, _0_0) or NEG0?
111 return s, c
114def _sin1cos2(sin1, cos1, sin2, cos2): # PYCHOK shared
115 '''(INTERNAL) Compute the C{sin1 * cos2} sine and its cosine.
117 @return: 2-Tuple C{(sin1 * cos2, hypot(sin1 * sin2, cos1)}.
118 '''
119 s = sin1 * cos2
120 c = _hypot(sin1 * sin2, cos1)
121 return s, c # _norm2(s, c)
124def _xnC4(**name_nC4):
125 '''(INTERNAL) Validate C{C4order}.
126 '''
127 n, nC4 = _xkwds_item2(name_nC4)
128 if nC4 not in _nC4s or not isinstance(nC4, int):
129 raise GeodesicError(n, nC4, txt_not_=_or(*map(str, _nC4s)))
130 return _nC4s[nC4]
133# **) MIT License
134#
135# Copyright (C) 2016-2024 -- mrJean1 at Gmail -- All Rights Reserved.
136#
137# Permission is hereby granted, free of charge, to any person obtaining a
138# copy of this software and associated documentation files (the "Software"),
139# to deal in the Software without restriction, including without limitation
140# the rights to use, copy, modify, merge, publish, distribute, sublicense,
141# and/or sell copies of the Software, and to permit persons to whom the
142# Software is furnished to do so, subject to the following conditions:
143#
144# The above copyright notice and this permission notice shall be included
145# in all copies or substantial portions of the Software.
146#
147# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
148# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
149# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
150# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
151# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
152# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
153# OTHER DEALINGS IN THE SOFTWARE.