Coverage for pygeodesy/fsums.py: 95%
698 statements
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2# -*- coding: utf-8 -*-
4u'''Class L{Fsum} for precision floating point summation and I{running}
5summation, based on respectively similar to Python's C{math.fsum}.
7Generally, an L{Fsum} instance is considered a C{float} plus a small or zero
8C{residual} value, see property L{Fsum.residual}. However, there are several
9C{integer} L{Fsum} cases, for example the result of C{ceil}, C{floor},
10C{Fsum.__floordiv__} and methods L{Fsum.fint} and L{Fsum.fint2}.
12Also, L{Fsum} methods L{Fsum.pow}, L{Fsum.__ipow__}, L{Fsum.__pow__} and
13L{Fsum.__rpow__} return a (very long) C{int} if invoked with optional argument
14C{mod} set to C{None}. The C{residual} of an C{integer} L{Fsum} may be between
15C{-1.0} and C{+1.0}, including C{INT0} if considered to be I{exact}.
17Set env variable C{PYGEODESY_FSUM_PARTIALS} to an empty string (or anything
18other than C{"fsum"}) for backward compatible summation of L{Fsum} partials.
20Set env variable C{PYGEODESY_FSUM_RESIDUAL} to a C{float} string for the
21threshold to throw a L{ResidualError} in division or exponention of an L{Fsum}
22instance with a I{relative} C{residual} exceeding the threshold, see methods
23L{Fsum.RESIDUAL}, L{Fsum.pow}, L{Fsum.__ipow__} and L{Fsum.__itruediv__}.
24'''
25# make sure int/int division yields float quotient, see .basics
26from __future__ import division as _; del _ # PYCHOK semicolon
28from pygeodesy.basics import iscomplex, isint, isscalar, map1, neg, \
29 signOf, _signOf
30from pygeodesy.constants import INT0, _isfinite, isinf, isnan, \
31 _0_0, _1_0, _N_1_0
32from pygeodesy.errors import itemsorted, _OverflowError, _TypeError, \
33 _ValueError, _xError2, _xkwds_get, _xkwds_get_, \
34 _ZeroDivisionError
35from pygeodesy.interns import NN, _arg_, _COMMASPACE_, _DASH_, _EQUAL_, \
36 _exceeds_, _from_, _iadd_, _LANGLE_, _negative_, \
37 _NOTEQUAL_, _not_finite_, _not_scalar_, \
38 _PERCENT_, _PLUS_, _R_, _RANGLE_, _SLASH_, \
39 _SPACE_, _STAR_, _UNDER_
40from pygeodesy.lazily import _ALL_LAZY, _getenv, _sys, _sys_version_info2
41from pygeodesy.named import _Named, _NamedTuple, _NotImplemented, Fmt, unstr
42from pygeodesy.props import _allPropertiesOf_n, deprecated_property_RO, \
43 Property_RO, property_RO
44# from pygeodesy.streprs import Fmt, unstr # from .named
45from pygeodesy.units import Float, Int
47from math import ceil as _ceil, fabs, floor as _floor # PYCHOK used! .ltp
49__all__ = _ALL_LAZY.fsums
50__version__ = '23.03.19'
52_add_op_ = _PLUS_
53_eq_op_ = _EQUAL_ * 2 # _DEQUAL_
54_COMMASPACE_R_ = _COMMASPACE_ + _R_
55_exceeds_R_ = _SPACE_ + _exceeds_(_R_)
56_floordiv_op_ = _SLASH_ * 2 # _DSLASH_
57_fset_op_ = _EQUAL_
58_ge_op_ = _RANGLE_ + _EQUAL_
59_gt_op_ = _RANGLE_
60_integer_ = 'integer'
61_le_op_ = _LANGLE_ + _EQUAL_
62_lt_op_ = _LANGLE_
63_mod_op_ = _PERCENT_
64_mul_op_ = _STAR_
65_ne_op_ = _NOTEQUAL_
66_non_zero_ = 'non-zero'
67_pow_op_ = _STAR_ * 2 # _DSTAR_, in .fmath
68_sub_op_ = _DASH_
69_truediv_op_ = _SLASH_
70_divmod_op_ = _floordiv_op_ + _mod_op_
72_pos_self = _1_0.__pos__() is _1_0 # in .vector3dBase
75def _2float(index=None, **name_value):
76 '''(INTERNAL) Raise C{TypeError} or C{ValueError} if not scalar or infinite.
77 '''
78 n, v = name_value.popitem() # _xkwds_popitem(name_value)
79 try:
80 v = float(v)
81 if _isfinite(v):
82 return v
83 E, t = _ValueError, _not_finite_
84 except Exception as X:
85 E, t = _xError2(X)
86 if index is not None:
87 n = Fmt.SQUARE(n, index)
88 raise E(n, v, txt=t)
91def _2floats(xs, origin=0, primed=False, sub=False, floats=False):
92 '''(INTERNAL) Yield all B{C{xs}} as C{float}s.
93 '''
94 _2f = _2float
95 if primed:
96 yield _1_0
97 i = origin
98 for x in xs:
99 if floats:
100 yield x
101 elif isinstance(x, Fsum):
102 ps = x._ps
103 if ps:
104 if sub:
105 ps = map(neg, ps)
106 for x in ps:
107 yield x
108 else:
109 x = _2f(index=i, xs=x)
110 if x:
111 yield (-x) if sub else x
112 i += 1
113 if primed:
114 yield _N_1_0
117def _Powers(power, xs, origin=1): # in .fmath
118 '''(INTERNAL) Yield each C{xs} as C{float(x**power)}.
119 '''
120 i = None
121 s = 2 == power
122 _2f = _2float
123 try:
124 for i, x in enumerate(xs):
125 if isinstance(x, Fsum):
126 T = x._mul_Fsum(x) if s else x.pow(power)
127 for t in T._ps:
128 yield t
129 else:
130 t = _2f(_=x)
131 if t:
132 yield _2f(__=t**power)
133 except Exception as X:
134 E, t = _xError2(X)
135 if i is None:
136 i = Fmt.PARENSPACED(xs=xs)
137 else:
138 i = Fmt.SQUARE(xs=i + origin)
139 i = Fmt.PARENSPACED(i, x)
140 raise E(i, txt=t)
143def _psum(ps): # PYCHOK used!
144 '''(INTERNAL) Partials summation updating C{ps}, I{overridden below}.
145 '''
146 i = len(ps) - 1 # len(ps) > 2
147 s = ps[i]
148 _2s = _2sum
149 while i > 0:
150 i -= 1
151 s, r = _2s(s, ps[i])
152 if r: # sum(ps) became inexact
153 ps[i:] = [s, r] if s else [r]
154 if i > 0:
155 p = ps[i-1] # round half-even
156 if (p > 0 and r > 0) or \
157 (p < 0 and r < 0): # signs match
158 r *= 2
159 t = s + r
160 if r == (t - s):
161 s = t
162 break
163 ps[i:] = [s]
164 return s
167def _2scalar(other, _raiser=None):
168 '''(INTERNAL) Return B{C{other}} as C{int}, C{float} or C{as-is}.
169 '''
170 if isinstance(other, Fsum):
171 s, r = other._fint2
172 if r:
173 s, r = other._fprs2
174 if r: # PYCHOK no cover
175 if _raiser and _raiser(r, s):
176 raise ValueError(_stresidual(_non_zero_, r))
177 s = other # L{Fsum} as-is
178 else:
179 s = other # C{type} as-is
180 if isint(s, both=True):
181 s = int(s)
182 return s
185def _strcomplex(s, *args):
186 '''(INTERNAL) C{Complex} 2- or 3-arg C{pow} error C{str}.
187 '''
188 c = iscomplex.__name__[2:]
189 n = _DASH_(len(args), _arg_)
190 t = _SPACE_(c, s, _from_, n, pow.__name__)
191 return unstr(t, *args)
194def _stresidual(prefix, residual, **name_values):
195 '''(INTERNAL) Residual error C{str}.
196 '''
197 p = _SPACE_(prefix, Fsum.residual.name)
198 t = Fmt.PARENSPACED(p, Fmt(residual))
199 for n, v in itemsorted(name_values):
200 n = n.replace(_UNDER_, _SPACE_)
201 p = Fmt.PARENSPACED(n, Fmt(v))
202 t = _COMMASPACE_(t, p)
203 return t
206def _2sum(a, b): # by .testFmath
207 '''(INTERNAL) Return C{a + b} as 2-tuple (sum, residual).
208 '''
209 s = a + b
210 if not _isfinite(s):
211 u = unstr(_2sum.__name__, a, b)
212 t = Fmt.PARENSPACED(_not_finite_, s)
213 raise _OverflowError(u, txt=t)
214 r = (a - (s - b)) if fabs(a) < fabs(b) else \
215 (b - (s - a)) # fabs(a) >= fabs(b)
216 return s, r
219class Fsum(_Named): # sync __methods__ with .vector3dBase.Vector3dBase
220 '''Precision floating point I{running} summation.
222 Unlike Python's C{math.fsum}, this class accumulates values and provides intermediate,
223 I{running} precision floating point summation. Accumulation may continue after
224 intermediate, I{running} summuation.
226 @note: Accumulated values may be L{Fsum} or C{scalar} instances with C{scalar} meaning
227 type C{float}, C{int} or any C{type} convertible to a single C{float}, having
228 method C{__float__}.
230 @note: Handling of exceptions and C{inf}, C{INF}, C{nan} and C{NAN} differs from
231 Python's C{math.fsum}.
233 @see: U{Hettinger<https://GitHub.com/ActiveState/code/blob/master/recipes/Python/
234 393090_Binary_floating_point_summatiaccurate_full/recipe-393090.py>}, U{Kahan
235 <https://WikiPedia.org/wiki/Kahan_summation_algorithm>}, U{Klein
236 <https://Link.Springer.com/article/10.1007/s00607-005-0139-x>}, Python 2.6+
237 file I{Modules/mathmodule.c} and the issue log U{Full precision summation
238 <https://Bugs.Python.org/issue2819>}.
239 '''
240 _math_fsum = None
241 _n = 0
242# _ps = [] # partial sums
243# _px = 0
244 _ratio = None
245 _RESIDUAL = max(float(_getenv('PYGEODESY_FSUM_RESIDUAL', _0_0)), _0_0)
247 def __init__(self, *xs, **name_RESIDUAL):
248 '''New L{Fsum} for precision floating point I{running} summation.
250 @arg xs: No, one or more initial values (each C{scalar} or an
251 L{Fsum} instance).
252 @kwarg name_RESIDUAL: Optional C{B{name}=NN} for this L{Fsum}
253 (C{str}) and C{B{RESIDUAL}=None} for the
254 L{ResidualError} threshold.
256 @see: Methods L{Fsum.fadd} and L{Fsum.RESIDUAL}.
257 '''
258 if name_RESIDUAL:
259 n, r = _xkwds_get_(name_RESIDUAL, name=NN, RESIDUAL=None)
260 if n: # set name ...
261 self.name = n
262 if r is not None:
263 self.RESIDUAL(r) # ... for ResidualError
264# self._n = 0
265 self._ps = [] # [_0_0], see L{Fsum._fprs}
266 if len(xs) > 1:
267 self._facc(_2floats(xs, origin=1), up=False)
268 elif xs: # len(xs) == 1
269 self._ps = [_2float(x=xs[0])]
270 self._n = 1
272 def __abs__(self):
273 '''Return this instance' absolute value as an L{Fsum}.
274 '''
275 s = _fsum(self._ps_1()) # == self._cmp_0(0, ...)
276 return self._copy_n(self.__abs__) if s < 0 else \
277 self._copy_2(self.__abs__)
279 def __add__(self, other):
280 '''Return the C{Fsum(B{self}, B{other})}.
282 @arg other: An L{Fsum} or C{scalar}.
284 @return: The sum (L{Fsum}).
286 @see: Method L{Fsum.__iadd__}.
287 '''
288 f = self._copy_2(self.__add__)
289 return f._fadd(other, _add_op_)
291 def __bool__(self): # PYCHOK not special in Python 2-
292 '''Return C{True} if this instance is non-zero.
293 '''
294 return self != 0
296 def __ceil__(self): # PYCHOK not special in Python 2-
297 '''Return this instance' C{math.ceil} as C{int} or C{float}.
299 @return: An C{int} in Python 3+, but C{float} in Python 2-.
301 @see: Methods L{Fsum.__floor__} and property L{Fsum.ceil}.
302 '''
303 return self.ceil
305 def __cmp__(self, other): # Python 2-
306 '''Compare this with an other instance or scalar.
308 @return: -1, 0 or +1 (C{int}).
310 @raise TypeError: Incompatible B{C{other}} C{type}.
311 '''
312 s = self._cmp_0(other, self.cmp.__name__)
313 return -1 if s < 0 else (+1 if s > 0 else 0)
315 cmp = __cmp__
317 def __divmod__(self, other):
318 '''Return C{divmod(B{self}, B{other})} as 2-tuple C{(quotient,
319 remainder)}, an C{int} in Python 3+ or C{float} in Python 2-
320 and an L{Fsum}.
322 @arg other: An L{Fsum} or C{scalar} modulus.
324 @see: Method L{Fsum.__itruediv__}.
325 '''
326 f = self._copy_2(self.__divmod__)
327 return f._fdivmod2(other, _divmod_op_)
329 def __eq__(self, other):
330 '''Compare this with an other instance or scalar.
331 '''
332 return self._cmp_0(other, _eq_op_) == 0
334 def __float__(self):
335 '''Return this instance' current precision running sum as C{float}.
337 @see: Methods L{Fsum.fsum} and L{Fsum.int_float}.
338 '''
339 return float(self._fprs)
341 def __floor__(self): # PYCHOK not special in Python 2-
342 '''Return this instance' C{math.floor} as C{int} or C{float}.
344 @return: An C{int} in Python 3+, but C{float} in Python 2-.
346 @see: Methods L{Fsum.__ceil__} and property L{Fsum.floor}.
347 '''
348 return self.floor
350 def __floordiv__(self, other):
351 '''Return C{B{self} // B{other}} as an L{Fsum}.
353 @arg other: An L{Fsum} or C{scalar} divisor.
355 @return: The C{floor} quotient (L{Fsum}).
357 @see: Methods L{Fsum.__ifloordiv__}.
358 '''
359 f = self._copy_2(self.__floordiv__)
360 return f._floordiv(other, _floordiv_op_)
362 def __format__(self, *other): # PYCHOK no cover
363 '''Not implemented.'''
364 return _NotImplemented(self, *other)
366 def __ge__(self, other):
367 '''Compare this with an other instance or scalar.
368 '''
369 return self._cmp_0(other, _ge_op_) >= 0
371 def __gt__(self, other):
372 '''Compare this with an other instance or scalar.
373 '''
374 return self._cmp_0(other, _gt_op_) > 0
376 def __hash__(self): # PYCHOK no cover
377 '''Return this instance' C{hash}.
378 '''
379 return hash(self._ps) # XXX id(self)?
381 def __iadd__(self, other):
382 '''Apply C{B{self} += B{other}} to this instance.
384 @arg other: An L{Fsum} or C{scalar} instance.
386 @return: This instance, updated (L{Fsum}).
388 @raise TypeError: Invalid B{C{other}}, not
389 C{scalar} nor L{Fsum}.
391 @see: Methods L{Fsum.fadd} and L{Fsum.fadd_}.
392 '''
393 return self._fadd(other, _iadd_)
395 def __ifloordiv__(self, other):
396 '''Apply C{B{self} //= B{other}} to this instance.
398 @arg other: An L{Fsum} or C{scalar} divisor.
400 @return: This instance, updated (L{Fsum}).
402 @raise ResidualError: Non-zero residual in B{C{other}}.
404 @raise TypeError: Invalid B{C{other}} type.
406 @raise ValueError: Invalid or non-finite B{C{other}}.
408 @raise ZeroDivisionError: Zero B{C{other}}.
410 @see: Methods L{Fsum.__itruediv__}.
411 '''
412 return self._floordiv(other, _floordiv_op_ + _fset_op_)
414 def __imatmul__(self, other): # PYCHOK no cover
415 '''Not implemented.'''
416 return _NotImplemented(self, other)
418 def __imod__(self, other):
419 '''Apply C{B{self} %= B{other}} to this instance.
421 @arg other: An L{Fsum} or C{scalar} modulus.
423 @return: This instance, updated (L{Fsum}).
425 @see: Method L{Fsum.__divmod__}.
426 '''
427 self._fdivmod2(other, _mod_op_ + _fset_op_)
428 return self
430 def __imul__(self, other):
431 '''Apply C{B{self} *= B{other}} to this instance.
433 @arg other: An L{Fsum} or C{scalar} factor.
435 @return: This instance, updated (L{Fsum}).
437 @raise OverflowError: Partial C{2sum} overflow.
439 @raise TypeError: Invalid B{C{other}} type.
441 @raise ValueError: Invalid or non-finite B{C{other}}.
442 '''
443 return self._fmul(other, _mul_op_ + _fset_op_)
445 def __int__(self):
446 '''Return this instance as an C{int}.
448 @see: Methods L{Fsum.int_float}, L{Fsum.__ceil__}
449 and L{Fsum.__floor__} and properties
450 L{Fsum.ceil} and L{Fsum.floor}.
451 '''
452 i, _ = self._fint2
453 return i
455 def __invert__(self): # PYCHOK no cover
456 '''Not implemented.'''
457 # Luciano Ramalho, "Fluent Python", 2nd Ed, page 567, O'Reilly, 2022
458 return _NotImplemented(self)
460 def __ipow__(self, other, *mod): # PYCHOK 2 vs 3 args
461 '''Apply C{B{self} **= B{other}} to this instance.
463 @arg other: The exponent (L{Fsum} or C{scalar}).
464 @arg mod: Optional modulus (C{int} or C{None}) for the
465 3-argument C{pow(B{self}, B{other}, B{mod})}
466 version.
468 @return: This instance, updated (L{Fsum}).
470 @note: If B{C{mod}} is given, the result will be an C{integer}
471 L{Fsum} in Python 3+ if this instance C{is_integer} or
472 set to C{as_integer} if B{C{mod}} given as C{None}.
474 @raise OverflowError: Partial C{2sum} overflow.
476 @raise ResidualError: Non-zero residual in B{C{other}} and
477 env var C{PYGEODESY_FSUM_RESIDUAL}
478 set or this instance has a non-zero
479 residual and either B{C{mod}} is
480 given and non-C{None} or B{C{other}}
481 is a negative or fractional C{scalar}.
483 @raise TypeError: Invalid B{C{other}} type or 3-argument
484 C{pow} invocation failed.
486 @raise ValueError: If B{C{other}} is a negative C{scalar}
487 and this instance is C{0} or B{C{other}}
488 is a fractional C{scalar} and this
489 instance is negative or has a non-zero
490 residual or B{C{mod}} is given and C{0}.
492 @see: CPython function U{float_pow<https://GitHub.com/
493 python/cpython/blob/main/Objects/floatobject.c>}.
494 '''
495 return self._fpow(other, _pow_op_ + _fset_op_, *mod)
497 def __isub__(self, other):
498 '''Apply C{B{self} -= B{other}} to this instance.
500 @arg other: An L{Fsum} or C{scalar}.
502 @return: This instance, updated (L{Fsum}).
504 @raise TypeError: Invalid B{C{other}} type.
506 @see: Method L{Fsum.fadd}.
507 '''
508 return self._fsub(other, _sub_op_ + _fset_op_)
510 def __iter__(self):
511 '''Return an C{iter}ator over a C{partials} duplicate.
512 '''
513 return iter(self.partials)
515 def __itruediv__(self, other):
516 '''Apply C{B{self} /= B{other}} to this instance.
518 @arg other: An L{Fsum} or C{scalar} divisor.
520 @return: This instance, updated (L{Fsum}).
522 @raise OverflowError: Partial C{2sum} overflow.
524 @raise ResidualError: Non-zero residual in B{C{other}} and
525 env var C{PYGEODESY_FSUM_RESIDUAL} set.
527 @raise TypeError: Invalid B{C{other}} type.
529 @raise ValueError: Invalid or non-finite B{C{other}}.
531 @raise ZeroDivisionError: Zero B{C{other}}.
533 @see: Method L{Fsum.__ifloordiv__}.
534 '''
535 return self._ftruediv(other, _truediv_op_ + _fset_op_)
537 def __le__(self, other):
538 '''Compare this with an other instance or scalar.
539 '''
540 return self._cmp_0(other, _le_op_) <= 0
542 def __len__(self):
543 '''Return the I{total} number accumulations (C{int}).
544 '''
545 return self._n
547 def __lt__(self, other):
548 '''Compare this with an other instance or scalar.
549 '''
550 return self._cmp_0(other, _lt_op_) < 0
552 def __matmul__(self, other): # PYCHOK no cover
553 '''Not implemented.'''
554 return _NotImplemented(self, other)
556 def __mod__(self, other):
557 '''Return C{B{self} % B{other}} as an L{Fsum}.
559 @see: Method L{Fsum.__imod__}.
560 '''
561 f = self._copy_2(self.__mod__)
562 return f._fdivmod2(other, _mod_op_)[1]
564 def __mul__(self, other):
565 '''Return C{B{self} * B{other}} as an L{Fsum}.
567 @see: Method L{Fsum.__imul__}.
568 '''
569 f = self._copy_2(self.__mul__)
570 return f._fmul(other, _mul_op_)
572 def __ne__(self, other):
573 '''Compare this with an other instance or scalar.
574 '''
575 return self._cmp_0(other, _ne_op_) != 0
577 def __neg__(self):
578 '''Return I{a copy of} this instance, negated.
579 '''
580 return self._copy_n(self.__neg__)
582 def __pos__(self):
583 '''Return this instance I{as-is}, like C{float.__pos__()}.
584 '''
585 return self if _pos_self else self._copy_2(self.__pos__)
587 def __pow__(self, other, *mod): # PYCHOK 2 vs 3 args
588 '''Return C{B{self}**B{other}} as an L{Fsum}.
590 @see: Method L{Fsum.__ipow__}.
591 '''
592 f = self._copy_2(self.__pow__)
593 return f._fpow(other, _pow_op_, *mod)
595 def __radd__(self, other):
596 '''Return C{B{other} + B{self}} as an L{Fsum}.
598 @see: Method L{Fsum.__iadd__}.
599 '''
600 f = self._copy_r2(other, self.__radd__)
601 return f._fadd(self, _add_op_)
603 def __rdivmod__(self, other):
604 '''Return C{divmod(B{other}, B{self})} as 2-tuple C{(quotient,
605 remainder)}.
607 @see: Method L{Fsum.__divmod__}.
608 '''
609 f = self._copy_r2(other, self.__rdivmod__)
610 return f._fdivmod2(self, _divmod_op_)
612# def __repr__(self):
613# '''Return the default C{repr(this)}.
614# '''
615# return self.toRepr(lenc=True)
617 def __rfloordiv__(self, other):
618 '''Return C{B{other} // B{self}} as an L{Fsum}.
620 @see: Method L{Fsum.__ifloordiv__}.
621 '''
622 f = self._copy_r2(other, self.__rfloordiv__)
623 return f._floordiv(self, _floordiv_op_)
625 def __rmatmul__(self, other): # PYCHOK no cover
626 '''Not implemented.'''
627 return _NotImplemented(self, other)
629 def __rmod__(self, other):
630 '''Return C{B{other} % B{self}} as an L{Fsum}.
632 @see: Method L{Fsum.__imod__}.
633 '''
634 f = self._copy_r2(other, self.__rmod__)
635 return f._fdivmod2(self, _mod_op_)[1]
637 def __rmul__(self, other):
638 '''Return C{B{other} * B{self}} as an L{Fsum}.
640 @see: Method L{Fsum.__imul__}.
641 '''
642 f = self._copy_r2(other, self.__rmul__)
643 return f._fmul(self, _mul_op_)
645 def __round__(self, ndigits=None): # PYCHOK no cover
646 '''Not implemented.'''
647 return _NotImplemented(self, ndigits=ndigits)
649 def __rpow__(self, other, *mod):
650 '''Return C{B{other}**B{self}} as an L{Fsum}.
652 @see: Method L{Fsum.__ipow__}.
653 '''
654 f = self._copy_r2(other, self.__rpow__)
655 return f._fpow(self, _pow_op_, *mod)
657 def __rsub__(self, other):
658 '''Return C{B{other} - B{self}} as L{Fsum}.
660 @see: Method L{Fsum.__isub__}.
661 '''
662 f = self._copy_r2(other, self.__rsub__)
663 return f._fsub(self, _sub_op_)
665 def __rtruediv__(self, other):
666 '''Return C{B{other} / B{self}} as an L{Fsum}.
668 @see: Method L{Fsum.__itruediv__}.
669 '''
670 f = self._copy_r2(other, self.__rtruediv__)
671 return f._ftruediv(self, _truediv_op_)
673 def __sizeof__(self): # PYCHOK not special in Python 2-
674 '''Return the current size of this instance in C{bytes}.
675 '''
676 return sum(map1(_sys.getsizeof, self._fint2,
677 self._fint2[0],
678 self._fint2[1],
679 self._fprs,
680 self._fprs2,
681 self._fprs2.fsum,
682 self._fprs2.residual,
683 self._n,
684 self._ps, *self._ps))
686 def __str__(self):
687 '''Return the default C{str(self)}.
688 '''
689 return self.toStr(lenc=True)
691 def __sub__(self, other):
692 '''Return C{B{self} - B{other}} as an L{Fsum}.
694 @arg other: An L{Fsum} or C{scalar}.
696 @return: The difference (L{Fsum}).
698 @see: Method L{Fsum.__isub__}.
699 '''
700 f = self._copy_2(self.__sub__)
701 return f._fsub(other, _sub_op_)
703 def __truediv__(self, other):
704 '''Return C{B{self} / B{other}} as an L{Fsum}.
706 @arg other: An L{Fsum} or C{scalar} divisor.
708 @return: The quotient (L{Fsum}).
710 @see: Method L{Fsum.__itruediv__}.
711 '''
712 f = self._copy_2(self.__truediv__)
713 return f._ftruediv(other, _truediv_op_)
715 __trunc__ = __int__
717 if _sys_version_info2 < (3, 0): # PYCHOK no cover
718 # <https://docs.Python.org/2/library/operator.html#mapping-operators-to-functions>
719 __div__ = __truediv__
720 __idiv__ = __itruediv__
721 __long__ = __int__
722 __nonzero__ = __bool__
723 __rdiv__ = __rtruediv__
725 def as_integer_ratio(self):
726 '''Return this instance as the ratio of 2 integers.
728 @return: 2-Tuple C{(numerator, denominator)} both
729 C{int} and with positive C{denominator}.
731 @see: Standard C{float.as_integer_ratio} in Python 3+.
732 '''
733 n, r = self._fint2
734 if r:
735 i, d = r.as_integer_ratio()
736 n *= d
737 n += i
738 else: # PYCHOK no cover
739 d = 1
740 return n, d
742 @property_RO
743 def ceil(self):
744 '''Get this instance' C{ceil} value (C{int} in Python 3+,
745 but C{float} in Python 2-).
747 @note: The C{ceil} takes the C{residual} into account.
749 @see: Method L{Fsum.int_float} and properties L{Fsum.floor},
750 L{Fsum.imag} and L{Fsum.real}.
751 '''
752 s, r = self._fprs2
753 c = _ceil(s) + int(r) - 1
754 while r > (c - s): # (s + r) > c
755 c += 1
756 return c
758 def _cmp_0(self, other, op):
759 '''(INTERNAL) Return C{scalar(self - B{other})} for 0-comparison.
760 '''
761 if isscalar(other):
762 s = _fsum(self._ps_1(other))
763 elif isinstance(other, Fsum):
764 s = _fsum(self._ps_1(*other._ps))
765 else:
766 raise self._TypeError(op, other) # txt=_invalid_
767 return s
769 def copy(self, deep=False, name=NN):
770 '''Copy this instance, C{shallow} or B{C{deep}}.
772 @return: The copy (L{Fsum}).
773 '''
774 f = _Named.copy(self, deep=deep, name=name)
775 f._n = self._n if deep else 1
776 f._ps = list(self._ps) # separate list
777 return f
779 def _copy_0(self, *xs):
780 '''(INTERNAL) Copy with/-out overriding C{partials}.
781 '''
782 # for x in xs:
783 # assert isscalar(x)
784 f = self._Fsum(self._n + len(xs), *xs)
785 if self.name:
786 f._name = self.name # .rename calls _update_attrs
787 return f
789 def _copy_2(self, which):
790 '''(INTERNAL) Copy for I{dyadic} operators.
791 '''
792 # NOT .classof due to .Fdot(a, *b) args, etc.
793 f = _Named.copy(self, deep=False, name=which.__name__)
794 # assert f._n == self._n
795 f._ps = list(self._ps) # separate list
796 return f
798 def _copy_n(self, which):
799 '''(INTERNAL) Negated copy for I{monadic} C{__abs__} and C{__neg__}.
800 '''
801 if self._ps:
802 f = self._Fsum(self._n)
803 f._ps[:] = self._ps_n()
804# f._facc_up(up=False)
805 else:
806 f = self._Fsum(self._n, _0_0)
807 f._name = which.__name__ # .rename calls _update_attrs
808 return f
810 def _copy_r2(self, other, which):
811 '''(INTERNAL) Copy for I{reverse-dyadic} operators.
812 '''
813 return other._copy_2(which) if isinstance(other, Fsum) else \
814 Fsum(other, name=which.__name__) # see ._copy_2
816 def _copy_RESIDUAL(self, other):
817 '''(INTERNAL) Copy C{other._RESIDUAL}.
818 '''
819 R = other._RESIDUAL
820 if R is not Fsum._RESIDUAL:
821 self._RESIDUAL = R
823 def _copy_up(self, _fprs2=False):
824 '''(INTERNAL) Minimal, anonymous copy.
825 '''
826 f = self._Fsum(self._n, *self._ps)
827 if _fprs2: # only the ._fprs2 2-tuple
828 Fsum._fprs2._update_from(f, self)
829 return f
831 def divmod(self, other):
832 '''Return C{divmod(B{self}, B{other})} as 2-tuple C{(quotient,
833 remainder)}.
835 @arg other: An L{Fsum} or C{scalar} divisor.
837 @return: 2-Tuple C{(quotient, remainder)}, with the C{quotient}
838 an C{int} in Python 3+ or a C{float} in Python 2- and
839 the C{remainder} an L{Fsum} instance.
841 @see: Method L{Fsum.__itruediv__}.
842 '''
843 f = self._copy_2(self.divmod)
844 return f._fdivmod2(other, _divmod_op_)
846 def _Error(self, op, other, Error, **txt):
847 '''(INTERNAL) Format an B{C{Error}} for C{{self} B{op} B{other}}.
848 '''
849 return Error(_SPACE_(self.toRepr(), op, repr(other)), **txt)
851 def _ErrorX(self, X, xs, **kwds): # in .fmath
852 '''(INTERNAL) Format a caught exception.
853 '''
854 E, t = _xError2(X)
855 n = unstr(self.named3, *xs[:3], _ELLIPSIS=len(xs) > 3, **kwds)
856 return E(n, txt=t, cause=X)
858 def _facc(self, xs, up=True): # from .elliptic._Defer.Fsum
859 '''(INTERNAL) Accumulate more known C{scalar}s.
860 '''
861 n, ps, _2s = 0, self._ps, _2sum
862 for x in xs: # _iter()
863 # assert isscalar(x) and isfinite(x)
864 i = 0
865 for p in ps:
866 x, p = _2s(x, p)
867 if p:
868 ps[i] = p
869 i += 1
870 ps[i:] = [x]
871 n += 1
872 # assert self._ps is ps
873 if n:
874 self._n += n
875 # Fsum._px = max(Fsum._px, len(ps))
876 if up:
877 self._update()
878 return self
880 def _facc_(self, *xs, **up):
881 '''(INTERNAL) Accumulate all positional C{scalar}s.
882 '''
883 return self._facc(xs, **up) if xs else self
885# def _facc_up(self, up=True):
886# '''(INTERNAL) Update the C{partials}, by removing
887# and re-accumulating the final C{partial}.
888# '''
889# while len(self._ps) > 1:
890# p = self._ps.pop()
891# if p:
892# n = self._n
893# self._facc_(p, up=False)
894# self._n = n
895# break
896# return self._update() if up else self # ._fpsqz()
898 def fadd(self, xs=()):
899 '''Add an iterable of C{scalar} or L{Fsum} instances
900 to this instance.
902 @arg xs: Iterable, list, tuple, etc. (C{scalar} or
903 L{Fsum} instances).
905 @return: This instance (L{Fsum}).
907 @raise OverflowError: Partial C{2sum} overflow.
909 @raise TypeError: An invalid B{C{xs}} type, not C{scalar}
910 nor L{Fsum}.
912 @raise ValueError: Invalid or non-finite B{C{xs}} value.
913 '''
914 if isinstance(xs, Fsum):
915 self._facc(xs._ps)
916 elif isscalar(xs): # for backward compatibility
917 self._facc_(_2float(x=xs)) # PYCHOK no cover
918 elif xs:
919 self._facc(_2floats(xs))
920 return self
922 def fadd_(self, *xs):
923 '''Add all positional C{scalar} or L{Fsum} instances
924 to this instance.
926 @arg xs: Values to add (C{scalar} or L{Fsum} instances),
927 all positional.
929 @return: This instance (L{Fsum}).
931 @raise OverflowError: Partial C{2sum} overflow.
933 @raise TypeError: An invalid B{C{xs}} type, not C{scalar}
934 nor L{Fsum}.
936 @raise ValueError: Invalid or non-finite B{C{xs}} value.
937 '''
938 return self._facc(_2floats(xs, origin=1))
940 def _fadd(self, other, op): # in .fmath.Fhorner
941 '''(INTERNAL) Apply C{B{self} += B{other}}.
942 '''
943 if isinstance(other, Fsum):
944 if other is self:
945 self._facc_(*other._ps) # == ._facc(tuple(other._ps))
946 elif other._ps:
947 self._facc(other._ps)
948 elif not isscalar(other):
949 raise self._TypeError(op, other) # txt=_invalid_
950 elif other:
951 self._facc_(other)
952 return self
954 fcopy = copy # for backward compatibility
955 fdiv = __itruediv__ # for backward compatibility
956 fdivmod = __divmod__ # for backward compatibility
958 def _fdivmod2(self, other, op):
959 '''(INTERNAL) C{divmod(B{self}, B{other})} as 2-tuple
960 (C{int} or C{float}, remainder C{self}).
961 '''
962 # result mostly follows CPython function U{float_divmod
963 # <https://GitHub.com/python/cpython/blob/main/Objects/floatobject.c>},
964 # but at least divmod(-3, 2) equals Cpython's result (-2, 1).
965 q = self._copy_up(_fprs2=True)._ftruediv(other, op).floor
966 if q: # == float // other == floor(float / other)
967 self -= other * q
969 s = signOf(other) # make signOf(self) == signOf(other)
970 if s and self.signOf() == -s: # PYCHOK no cover
971 self += other
972 q -= 1
974# t = self.signOf()
975# if t and t != s:
976# from pygeodesy.errors import _AssertionError
977# raise self._Error(op, other, _AssertionError, txt=signOf.__name__)
978 return q, self # q is C{int} in Python 3+, but C{float} in Python 2-
980 def _finite(self, other, op=None):
981 '''(INTERNAL) Return B{C{other}} if C{finite}.
982 '''
983 if _isfinite(other):
984 return other
985 raise ValueError(_not_finite_) if not op else \
986 self._ValueError(op, other, txt=_not_finite_)
988 def fint(self, raiser=True, name=NN):
989 '''Return this instance' current running sum as C{integer}.
991 @kwarg raiser: If C{True} throw a L{ResidualError} if the
992 I{integer} residual is non-zero.
993 @kwarg name: Optional name (C{str}), overriding C{"fint"}.
995 @return: The C{integer} (L{Fsum}).
997 @raise ResidualError: Non-zero I{integer} residual.
999 @see: Methods L{Fsum.int_float} and L{Fsum.is_integer}.
1000 '''
1001 i, r = self._fint2
1002 if r and raiser:
1003 t = _stresidual(_integer_, r)
1004 raise ResidualError(_integer_, i, txt=t)
1005 n = name or self.fint.__name__
1006 return Fsum(name=n)._fset(i, asis=True)
1008 def fint2(self, **name):
1009 '''Return this instance' current running sum as C{int} and
1010 the I{integer} residual.
1012 @kwarg name: Optional name (C{str}).
1014 @return: An L{Fsum2Tuple}C{(fsum, residual)} with C{fsum}
1015 an C{int} and I{integer} C{residual} a C{float} or
1016 C{INT0} if the C{fsum} is considered to be I{exact}.
1017 '''
1018 return Fsum2Tuple(*self._fint2, **name)
1020 @Property_RO
1021 def _fint2(self): # see ._fset
1022 '''(INTERNAL) Get 2-tuple (C{int}, I{integer} residual).
1023 '''
1024 i = int(self._fprs) # int(self)
1025 r = _fsum(self._ps_1(i)) if len(self._ps) > 1 else (
1026 (self._ps[0] - i) if self._ps else -i)
1027 return i, (r or INT0)
1029 @deprecated_property_RO
1030 def float_int(self): # PYCHOK no cover
1031 '''DEPRECATED, use method C{Fsum.int_float}.'''
1032 return self.int_float() # raiser=False
1034 @property_RO
1035 def floor(self):
1036 '''Get this instance' C{floor} (C{int} in Python 3+, but
1037 C{float} in Python 2-).
1039 @note: The C{floor} takes the C{residual} into account.
1041 @see: Method L{Fsum.int_float} and properties L{Fsum.ceil},
1042 L{Fsum.imag} and L{Fsum.real}.
1043 '''
1044 s, r = self._fprs2
1045 f = _floor(s) + _floor(r) + 1
1046 while r < (f - s): # (s + r) < f
1047 f -= 1
1048 return f
1050# floordiv = __floordiv__ # for naming consistency
1052 def _floordiv(self, other, op): # rather _ffloordiv?
1053 '''Apply C{B{self} //= B{other}}.
1054 '''
1055 q = self._ftruediv(other, op) # == self
1056 return self._fset(q.floor, asis=True) # floor(q)
1058 fmul = __imul__ # for backward compatibility
1060 def _fmul(self, other, op):
1061 '''(INTERNAL) Apply C{B{self} *= B{other}}.
1062 '''
1063 if isscalar(other):
1064 f = self._mul_scalar(other, op)
1065 elif not isinstance(other, Fsum):
1066 raise self._TypeError(op, other) # txt=_invalid_
1067 elif len(self._ps) != 1:
1068 f = self._mul_Fsum(other, op)
1069 elif len(other._ps) != 1: # len(self._ps) == 1
1070 f = other._copy_up()._mul_scalar(self._ps[0], op)
1071 else: # len(other._ps) == len(self._ps) == 1
1072 s = self._finite(self._ps[0] * other._ps[0])
1073 return self._fset(s, asis=True, n=len(self) + 1)
1074 return self._fset(f)
1076 def fover(self, over):
1077 '''Apply C{B{self} /= B{over}} and summate.
1079 @arg over: An L{Fsum} or C{scalar} denominator.
1081 @return: Precision running sum (C{float}).
1083 @see: Methods L{Fsum.fsum} and L{Fsum.__itruediv__}.
1084 '''
1085 return float(self.fdiv(over)._fprs)
1087 fpow = __ipow__ # for backward compatibility
1089 def _fpow(self, other, op, *mod):
1090 '''Apply C{B{self} **= B{other}}, optional B{C{mod}} or C{None}.
1091 '''
1092 if mod and mod[0] is not None: # == 3-arg C{pow}
1093 s = self._pow_3(other, mod[0], op)
1094 elif mod and mod[0] is None and self.is_integer():
1095 # return an exact C{int} for C{int}**C{int}
1096 i = self._copy_0(self._fint2[0]) # assert _fint2[1] == 0
1097 x = _2scalar(other) # C{int}, C{float} or other
1098 s = i._pow_2(x, other, op) if isscalar(x) else i._fpow(x, op)
1099 else: # pow(self, other) == pow(self, other, None)
1100 p = None
1101 if isinstance(other, Fsum):
1102 x, r = other._fprs2
1103 if r:
1104 if self._raiser(r, x):
1105 raise self._ResidualError(op, other, r)
1106 p = self._pow_scalar(r, other, op)
1107# p = _2scalar(p) # _raiser = None
1108 elif not isscalar(other):
1109 raise self._TypeError(op, other) # txt=_invalid_
1110 else:
1111 x = self._finite(other, op)
1112 s = self._pow_scalar(x, other, op)
1113 if p is not None:
1114 s *= p
1115 return self._fset(s, asis=isint(s), n=max(len(self), 1))
1117 @Property_RO
1118 def _fprs(self):
1119 '''(INTERNAL) Get and cache this instance' precision
1120 running sum (C{float} or C{int}), ignoring C{residual}.
1122 @note: The precision running C{fsum} after a C{//=} or
1123 C{//} C{floor} division is C{int} in Python 3+.
1124 '''
1125 ps = self._ps
1126 n = len(ps) - 1
1127 if n > 1:
1128 s = _psum(ps)
1129 elif n > 0: # len(ps) == 2
1130 s, p = _2sum(*ps) if ps[1] else ps
1131 ps[:] = ([p, s] if s else [p]) if p else [s]
1132 elif n < 0: # see L{Fsum.__init__}
1133 s = _0_0
1134 ps[:] = [s]
1135 else: # len(ps) == 1
1136 s = ps[0]
1137 # assert self._ps is ps
1138 # assert Fsum._fprs2.name not in self.__dict__
1139 return s
1141 @Property_RO
1142 def _fprs2(self):
1143 '''(INTERNAL) Get and cache this instance' precision
1144 running sum and residual (L{Fsum2Tuple}).
1145 '''
1146 s = self._fprs
1147 r = _fsum(self._ps_1(s)) if len(self._ps) > 1 else INT0
1148 return Fsum2Tuple(s, r) # name=Fsum.fsum2.__name__
1150# def _fpsqz(self):
1151# '''(INTERNAL) Compress, squeeze the C{partials}.
1152# '''
1153# if len(self._ps) > 2:
1154# _ = self._fprs
1155# return self
1157 def _fset(self, other, asis=False, n=1):
1158 '''(INTERNAL) Overwrite this instance with an other or a C{scalar}.
1159 '''
1160 if other is self:
1161 pass # from ._fmul, ._ftruediv and ._pow_scalar
1162 elif isinstance(other, Fsum):
1163 self._n = other._n
1164 self._ps[:] = other._ps
1165 self._copy_RESIDUAL(other)
1166 # use or zap the C{Property_RO} values
1167 Fsum._fint2._update_from(self, other)
1168 Fsum._fprs ._update_from(self, other)
1169 Fsum._fprs2._update_from(self, other)
1170 elif isscalar(other):
1171 s = other if asis else float(other)
1172 i = int(s) # see ._fint2
1173 t = i, ((s - i) or INT0)
1174 self._n = n
1175 self._ps[:] = [s]
1176 # Property_RO _fint2, _fprs and _fprs2 can't be a Property:
1177 # Property's _fset zaps the value just set by the @setter
1178 self.__dict__.update(_fint2=t, _fprs=s, _fprs2=Fsum2Tuple(s, INT0))
1179 else: # PYCHOK no cover
1180 raise self._TypeError(_fset_op_, other) # txt=_invalid_
1181 return self
1183 def fsub(self, xs=()):
1184 '''Subtract an iterable of C{scalar} or L{Fsum} instances
1185 from this instance.
1187 @arg xs: Iterable, list, tuple. etc. (C{scalar}
1188 or L{Fsum} instances).
1190 @return: This instance, updated (L{Fsum}).
1192 @see: Method L{Fsum.fadd}.
1193 '''
1194 return self._facc(_2floats(xs, sub=True)) if xs else self
1196 def fsub_(self, *xs):
1197 '''Subtract all positional C{scalar} or L{Fsum} instances
1198 from this instance.
1200 @arg xs: Values to subtract (C{scalar} or
1201 L{Fsum} instances), all positional.
1203 @return: This instance, updated (L{Fsum}).
1205 @see: Method L{Fsum.fadd}.
1206 '''
1207 return self._facc(_2floats(xs, origin=1, sub=True)) if xs else self
1209 def _fsub(self, other, op):
1210 '''(INTERNAL) Apply C{B{self} -= B{other}}.
1211 '''
1212 if isinstance(other, Fsum):
1213 if other is self: # or other._fprs2 == self._fprs2:
1214 self._fset(_0_0, asis=True, n=len(self) * 2) # self -= self
1215 elif other._ps:
1216 self._facc(other._ps_n())
1217 elif not isscalar(other):
1218 raise self._TypeError(op, other) # txt=_invalid_
1219 elif self._finite(other, op):
1220 self._facc_(-other)
1221 return self
1223 def _Fsum(self, n, *ps):
1224 '''(INTERNAL) New L{Fsum} instance.
1225 '''
1226 f = Fsum()
1227 f._n = n
1228 if ps:
1229 f._ps[:] = ps
1230 f._copy_RESIDUAL(self)
1231 return f
1233 def fsum(self, xs=()):
1234 '''Add more C{scalar} or L{Fsum} instances and summate.
1236 @kwarg xs: Iterable, list, tuple, etc. (C{scalar} or
1237 L{Fsum} instances).
1239 @return: Precision running sum (C{float} or C{int}).
1241 @see: Method L{Fsum.fadd}.
1243 @note: Accumulation can continue after summation.
1244 '''
1245 f = self._facc(_2floats(xs)) if xs else self
1246 return f._fprs
1248 def fsum_(self, *xs):
1249 '''Add all positional C{scalar} or L{Fsum} instances and summate.
1251 @arg xs: Values to add (C{scalar} or L{Fsum} instances),
1252 all positional.
1254 @return: Precision running sum (C{float} or C{int}).
1256 @see: Method L{Fsum.fsum}.
1257 '''
1258 f = self._facc(_2floats(xs, origin=1)) if xs else self
1259 return f._fprs
1261 def fsum2(self, xs=(), **name):
1262 '''Add more C{scalar} or L{Fsum} instances and return the
1263 current precision running sum and the C{residual}.
1265 @kwarg xs: Iterable, list, tuple, etc. (C{scalar} or
1266 L{Fsum} instances).
1267 @kwarg name: Optional name (C{str}).
1269 @return: L{Fsum2Tuple}C{(fsum, residual)} with C{fsum} the
1270 current precision running sum and C{residual}, the
1271 (precision) sum of the remaining C{partials}. The
1272 C{residual is INT0} if the C{fsum} is considered
1273 to be I{exact}.
1275 @see: Methods L{Fsum.fint2}, L{Fsum.fsum} and L{Fsum.fsum2_}
1276 '''
1277 f = self._facc(_2floats(xs)) if xs else self
1278 t = f._fprs2
1279 if name:
1280 t = t.dup(name=_xkwds_get(name, name=NN))
1281 return t
1283 def fsum2_(self, *xs):
1284 '''Add any positional C{scalar} or L{Fsum} instances and return
1285 the precision running sum and the C{differential}.
1287 @arg xs: Values to add (C{scalar} or L{Fsum} instances),
1288 all positional.
1290 @return: 2-Tuple C{(fsum, delta)} with the current precision
1291 running C{fsum} and C{delta}, the difference with
1292 the previous running C{fsum} (C{float}s).
1294 @see: Methods L{Fsum.fsum_} and L{Fsum.fsum}.
1295 '''
1296 p, r = self._fprs2
1297 if xs:
1298 s, t = self._facc(_2floats(xs, origin=1))._fprs2
1299 return s, _fsum((s, -p, r, -t)) # ((s - p) + (r - t))
1300 else: # PYCHOK no cover
1301 return p, _0_0
1303# ftruediv = __itruediv__ # for naming consistency
1305 def _ftruediv(self, other, op):
1306 '''(INTERNAL) Apply C{B{self} /= B{other}}.
1307 '''
1308 n = _1_0
1309 if isinstance(other, Fsum):
1310 if other is self or other._fprs2 == self._fprs2:
1311 return self._fset(_1_0, asis=True, n=len(self))
1312 d, r = other._fprs2
1313 if r:
1314 if not d: # PYCHOK no cover
1315 d = r
1316 elif self._raiser(r, d):
1317 raise self._ResidualError(op, other, r)
1318 else:
1319 d, n = other.as_integer_ratio()
1320 elif isscalar(other):
1321 d = other
1322 else: # PYCHOK no cover
1323 raise self._TypeError(op, other) # txt=_invalid_
1324 try:
1325 s = 0 if isinf(d) else (
1326 d if isnan(d) else self._finite(n / d))
1327 except Exception as x:
1328 E, t = _xError2(x)
1329 raise self._Error(op, other, E, txt=t)
1330 f = self._mul_scalar(s, _mul_op_) # handles 0, NAN, etc.
1331 return self._fset(f)
1333 @property_RO
1334 def imag(self):
1335 '''Get the C{imaginary} part of this instance (C{0.0}, always).
1337 @see: Properties L{Fsum.ceil}, L{Fsum.floor} and L{Fsum.real}.
1338 '''
1339 return _0_0
1341 def int_float(self, raiser=False):
1342 '''Return this instance' current running sum as C{int} or C{float}.
1344 @kwarg raiser: If C{True} throw a L{ResidualError} if the
1345 residual is non-zero.
1347 @return: This C{integer} sum if this instance C{is_integer},
1348 otherwise return the C{float} sum if the residual
1349 is zero or if C{B{raiser}=False}.
1351 @raise ResidualError: Non-zero residual and C{B{raiser}=True}.
1353 @see: Methods L{Fsum.fint} and L{Fsum.fint2}.
1354 '''
1355 s, r = self._fint2
1356 if r:
1357 s, r = self._fprs2
1358 if r and raiser: # PYCHOK no cover
1359 t = _stresidual(_non_zero_, r)
1360 raise ResidualError(int_float=s, txt=t)
1361 s = float(s) # redundant
1362 return s
1364 def is_exact(self):
1365 '''Is this instance' current running C{fsum} considered to
1366 be exact? (C{bool}).
1367 '''
1368 return self.residual is INT0
1370 def is_integer(self):
1371 '''Is this instance' current running sum C{integer}? (C{bool}).
1373 @see: Methods L{Fsum.fint} and L{Fsum.fint2}.
1374 '''
1375 _, r = self._fint2
1376 return False if r else True
1378 def is_math_fsum(self):
1379 '''Return whether functions L{fsum}, L{fsum_}, L{fsum1}
1380 and L{fsum1_} plus partials summation are based on
1381 Python's C{math.fsum} or not.
1383 @return: C{2} if all functions and partials summation
1384 are based on C{math.fsum}, C{True} if only
1385 the functions are based on C{math.fsum} (and
1386 partials summation is not) or C{False} if
1387 none are.
1388 '''
1389 f = Fsum._math_fsum
1390 return 2 if _psum is f else bool(f)
1392 def _mul_Fsum(self, other, op=_mul_op_):
1393 '''(INTERNAL) Return C{B{self} * Fsum B{other}} as L{Fsum}.
1394 '''
1395 # assert isinstance(other, Fsum)
1396 return self._copy_0()._facc(self._ps_x(op, *other._ps), up=False)
1398 def _mul_scalar(self, factor, op):
1399 '''(INTERNAL) Return C{B{self} * scalar B{factor}} as L{Fsum} or C{0}.
1400 '''
1401 # assert isscalar(factor)
1402 if self._finite(factor, op) and self._ps:
1403 if factor == _1_0:
1404 return self
1405 f = self._copy_0()._facc(self._ps_x(op, factor), up=False)
1406 else:
1407 f = self._copy_0(_0_0)
1408 return f
1410 @property_RO
1411 def partials(self):
1412 '''Get this instance' current partial sums (C{tuple} of C{float}s and/or C{int}s).
1413 '''
1414 return tuple(self._ps)
1416 def pow(self, x, *mod):
1417 '''Return C{B{self}**B{x}} as L{Fsum}.
1419 @arg x: The exponent (L{Fsum} or C{scalar}).
1420 @arg mod: Optional modulus (C{int} or C{None}) for the 3-argument
1421 C{pow(B{self}, B{other}, B{mod})} version.
1423 @return: The C{pow(self, B{x})} or C{pow(self, B{x}, *B{mod})}
1424 result (L{Fsum}).
1426 @note: If B{C{mod}} is given as C{None}, the result will be an
1427 C{integer} L{Fsum} provided this instance C{is_integer}
1428 or set C{integer} with L{Fsum.fint}.
1430 @see: Methods L{Fsum.__ipow__}, L{Fsum.fint} and L{Fsum.is_integer}.
1431 '''
1432 f = self._copy_2(self.pow)
1433 if f and isint(x) and x >= 0 and not mod:
1434 f._pow_int(x, x, _pow_op_) # f **= x
1435 else:
1436 f._fpow(x, _pow_op_, *mod) # f = pow(f, x, *mod)
1437 return f
1439 def _pow_0_1(self, x, other):
1440 '''(INTERNAL) Return B{C{self}**1} or C{B{self}**0 == 1.0}.
1441 '''
1442 return self if x else (1 if self.is_integer() and isint(other) else _1_0)
1444 def _pow_2(self, x, other, op):
1445 '''(INTERNAL) 2-arg C{pow(B{self}, scalar B{x})} embellishing errors.
1446 '''
1447 # assert len(self._ps) == 1 and isscalar(x)
1448 b = self._ps[0] # assert isscalar(b)
1449 try: # type(s) == type(x) if x in (_1_0, 1)
1450 s = pow(b, x) # -1**2.3 == -(1**2.3)
1451 if not iscomplex(s):
1452 return self._finite(s) # 0**INF == 0.0, 1**INF==1.0
1453 # neg**frac == complex in Python 3+, but ValueError in 2-
1454 E, t = _ValueError, _strcomplex(s, b, x) # PYCHOK no cover
1455 except Exception as x:
1456 E, t = _xError2(x)
1457 raise self._Error(op, other, E, txt=t)
1459 def _pow_3(self, other, mod, op):
1460 '''(INTERNAL) 3-arg C{pow(B{self}, B{other}, int B{mod} or C{None})}.
1461 '''
1462 b, r = self._fprs2 if mod is None else self._fint2
1463 if r and self._raiser(r, b):
1464 t = _non_zero_ if mod is None else _integer_
1465 E, t = ResidualError, _stresidual(t, r, mod=mod)
1466 else:
1467 try: # b, other, mod all C{int}, unless C{mod} is C{None}
1468 x = _2scalar(other, _raiser=self._raiser)
1469 s = pow(b, x, mod)
1470 if not iscomplex(s):
1471 return self._finite(s)
1472 # neg**frac == complex in Python 3+, but ValueError in 2-
1473 E, t = _ValueError, _strcomplex(s, b, x, mod) # PYCHOK no cover
1474 except Exception as x:
1475 E, t = _xError2(x)
1476 t = _COMMASPACE_(Fmt.PARENSPACED(mod=mod), t)
1477 raise self._Error(op, other, E, txt=t)
1479 def _pow_int(self, x, other, op):
1480 '''(INTERNAL) Return C{B{self} **= B{x}} for C{int B{x} >= 0}.
1481 '''
1482 # assert isint(x) and x >= 0
1483 if len(self._ps) > 1:
1484 if x > 2:
1485 p = self._copy_up()
1486 m = 1 # single-bit mask
1487 if x & m:
1488 x -= m # x ^= m
1489 f = p._copy_up()
1490 else:
1491 f = self._copy_0(_1_0)
1492 while x:
1493 p = p._mul_Fsum(p, op) # p **= 2
1494 m += m # m <<= 1
1495 if x & m:
1496 x -= m # x ^= m
1497 f = f._mul_Fsum(p, op) # f *= p
1498 elif x > 1: # self**2
1499 f = self._mul_Fsum(self, op)
1500 else: # self**1 or self**0
1501 f = self._pow_0_1(x, other)
1502 elif self._ps: # self._ps[0]**x
1503 f = self._pow_2(x, other, op)
1504 else: # PYCHOK no cover
1505 # 0**pos_int == 0, but 0**0 == 1
1506 f = 0 if x else 1 # like ._fprs
1507 return self._fset(f, asis=isint(f), n=len(self))
1509 def _pow_scalar(self, x, other, op):
1510 '''(INTERNAL) Return C{self**B{x}} for C{scalar B{x}}.
1511 '''
1512 s, r = self._fprs2
1513 if isint(x, both=True):
1514 x = int(x) # Fsum**int
1515 y = abs(x)
1516 if y > 1:
1517 if r:
1518 f = self._copy_up()._pow_int(y, other, op)
1519 if x > 0: # > 1
1520 return f
1521 # assert x < 0 # < -1
1522 s, r = f._fprs2
1523 if r:
1524 return self._copy_0(_1_0)._ftruediv(f, op)
1525 # use **= -1 for the CPython float_pow
1526 # error if s is zero, and not s = 1 / s
1527 x = -1
1528# elif y > 1: # self**2 or self**-2
1529# f = self._mul_Fsum(self, op)
1530# if x < 0:
1531# f = f._copy_0(_1_0)._ftruediv(f, op)
1532# return f
1533 elif x < 0: # self**-1 == 1 / self
1534 if r:
1535 return self._copy_0(_1_0)._ftruediv(self, op)
1536 else: # self**1 or self**0
1537 return self._pow_0_1(x, other) # self or 0.0
1538 elif not isscalar(x): # assert ...
1539 raise self._TypeError(op, other, txt=_not_scalar_)
1540 elif r and self._raiser(r, s): # non-zero residual**fractional
1541 # raise self._ResidualError(op, other, r, fractional_power=x)
1542 t = _stresidual(_non_zero_, r, fractional_power=x)
1543 raise self._Error(op, other, ResidualError, txt=t)
1544 # assert isscalar(s) and isscalar(x)
1545 return self._copy_0(s)._pow_2(x, other, op)
1547 def _ps_1(self, *less):
1548 '''(INTERNAL) Yield partials, 1-primed and subtract any C{less}.
1549 '''
1550 yield _1_0
1551 for p in self._ps:
1552 if p:
1553 yield p
1554 for p in less:
1555 if p:
1556 yield -p
1557 yield _N_1_0
1559 def _ps_n(self):
1560 '''(INTERNAL) Yield partials, negated.
1561 '''
1562 for p in self._ps:
1563 if p:
1564 yield -p
1566 def _ps_x(self, op, *factors): # see .fmath.Fhorner
1567 '''(INTERNAL) Yield all C{partials} times each B{C{factor}},
1568 in total, up to C{len(partials) * len(factors)} items.
1569 '''
1570 ps = self._ps
1571 if len(ps) < len(factors):
1572 ps, factors = factors, ps
1573 _f = _isfinite
1574 for f in factors:
1575 for p in ps:
1576 p *= f
1577 if _f(p):
1578 yield p
1579 else: # PYCHOK no cover
1580 self._finite(p, op) # throw ValueError
1582 @property_RO
1583 def real(self):
1584 '''Get the C{real} part of this instance (C{float}).
1586 @see: Methods L{Fsum.__float__} and L{Fsum.fsum}
1587 and properties L{Fsum.ceil}, L{Fsum.floor},
1588 L{Fsum.imag} and L{Fsum.residual}.
1589 '''
1590 return float(self._fprs)
1592 @property_RO
1593 def residual(self):
1594 '''Get this instance' residual (C{float} or C{int}), the
1595 C{sum(partials)} less the precision running sum C{fsum}.
1597 @note: If the C{residual is INT0}, the precision running
1598 C{fsum} is considered to be I{exact}.
1600 @see: Methods L{Fsum.fsum}, L{Fsum.fsum2} and L{Fsum.is_exact}.
1601 '''
1602 return self._fprs2.residual
1604 def _raiser(self, r, s):
1605 '''(INTERNAL) Does the ratio C{r / s} exceed threshold?
1606 '''
1607 self._ratio = t = fabs((r / s) if s else r)
1608 return t > self._RESIDUAL
1610 def RESIDUAL(self, *threshold):
1611 '''Get and set this instance' I{ratio} for raising L{ResidualError}s,
1612 overriding the default from env variable C{PYGEODESY_FSUM_RESIDUAL}.
1614 @arg threshold: If C{scalar}, the I{ratio} to exceed for raising
1615 L{ResidualError}s in division and exponention, if
1616 C{None} restore the default set with env variable
1617 C{PYGEODESY_FSUM_RESIDUAL} or if omitted, keep the
1618 current setting.
1620 @return: The previous C{RESIDUAL} setting (C{float}).
1622 @raise ValueError: Negative B{C{threshold}}.
1624 @note: A L{ResidualError} is thrown if the non-zero I{ratio}
1625 C{residual} / C{fsum} exceeds the B{C{threshold}}.
1626 '''
1627 r = self._RESIDUAL
1628 if threshold:
1629 t = threshold[0]
1630 t = Fsum._RESIDUAL if t is None else (
1631 float(t) if isscalar(t) else ( # for backward ...
1632 _0_0 if bool(t) else _1_0)) # ... compatibility
1633 if t < 0:
1634 u = self._unstr(self.RESIDUAL, *threshold)
1635 raise _ValueError(u, RESIDUAL=t, txt=_negative_)
1636 self._RESIDUAL = t
1637 return r
1639 def _ResidualError(self, op, other, residual):
1640 '''(INTERNAL) Non-zero B{C{residual}} etc.
1641 '''
1642 t = _stresidual(_non_zero_, residual, ratio=self._ratio,
1643 RESIDUAL=self._RESIDUAL)
1644 t = t.replace(_COMMASPACE_R_, _exceeds_R_)
1645 return self._Error(op, other, ResidualError, txt=t)
1647 def signOf(self, res=True):
1648 '''Determine the sign of this instance.
1650 @kwarg res: If C{True} consider, otherwise
1651 ignore the residual (C{bool}).
1653 @return: The sign (C{int}, -1, 0 or +1).
1654 '''
1655 s, r = self._fprs2 if res else (self._fprs, 0)
1656 return _signOf(r, -s)
1658 def toRepr(self, **prec_sep_fmt_lenc): # PYCHOK signature
1659 '''Return this C{Fsum} instance as representation.
1661 @kwarg prec_sep_fmt_lenc: Optional keyword arguments for
1662 method L{Fsum2Tuple.toRepr} plus C{B{lenc}=True}
1663 (C{bool}) to in-/exclude the current C{[len]}
1664 of this L{Fsum} enclosed in I{[brackets]}.
1666 @return: This instance (C{repr}).
1667 '''
1668 return self._toT(self._fprs2.toRepr, **prec_sep_fmt_lenc)
1670 def toStr(self, **prec_sep_fmt_lenc): # PYCHOK signature
1671 '''Return this C{Fsum} instance as string.
1673 @kwarg prec_sep_fmt_lenc: Optional keyword arguments for
1674 method L{Fsum2Tuple.toStr} plus C{B{lenc}=True}
1675 (C{bool}) to in-/exclude the current C{[len]}
1676 of this L{Fsum} enclosed in I{[brackets]}.
1678 @return: This instance (C{str}).
1679 '''
1680 return self._toT(self._fprs2.toStr, **prec_sep_fmt_lenc)
1682 def _toT(self, toT, fmt=Fmt.g, lenc=True, **kwds):
1683 '''(INTERNAL) Helper for C{toRepr} and C{toStr}.
1684 '''
1685 n = self.named3
1686 if lenc:
1687 n = Fmt.SQUARE(n, len(self))
1688 return _SPACE_(n, toT(fmt=fmt, **kwds))
1690 def _TypeError(self, op, other, **txt): # PYCHOK no cover
1691 '''(INTERNAL) Return a C{TypeError}.
1692 '''
1693 return self._Error(op, other, _TypeError, **txt)
1695 def _update(self): # see ._fset
1696 '''(INTERNAL) Zap all cached C{Property_RO} values.
1697 '''
1698 Fsum._fint2._update(self)
1699 Fsum._fprs ._update(self)
1700 Fsum._fprs2._update(self)
1701 return self
1703 def _ValueError(self, op, other, **txt): # PYCHOK no cover
1704 '''(INTERNAL) Return a C{ValueError}.
1705 '''
1706 return self._Error(op, other, _ValueError, **txt)
1708 def _ZeroDivisionError(self, op, other, **txt): # PYCHOK no cover
1709 '''(INTERNAL) Return a C{ZeroDivisionError}.
1710 '''
1711 return self._Error(op, other, _ZeroDivisionError, **txt)
1713_allPropertiesOf_n(3, Fsum, Property_RO) # PYCHOK assert, see Fsum._fset, -._update
1716def _Float_Int(arg, **name_Error):
1717 '''(INTERNAL) Unit of L{Fsum2Tuple} items.
1718 '''
1719 U = Int if isint(arg) else Float
1720 return U(arg, **name_Error)
1723class Fsum2Tuple(_NamedTuple):
1724 '''2-Tuple C{(fsum, residual)} with the precision running C{fsum}
1725 and the C{residual}, the sum of the remaining partials. Each
1726 item is either C{float} or C{int}.
1728 @note: If the C{residual is INT0}, the C{fsum} is considered
1729 to be I{exact}, see method L{Fsum2Tuple.is_exact}.
1730 '''
1731 _Names_ = ( Fsum.fsum.__name__, Fsum.residual.name)
1732 _Units_ = (_Float_Int, _Float_Int)
1734 @Property_RO
1735 def Fsum(self):
1736 '''Get this L{Fsum2Tuple} as an L{Fsum}.
1737 '''
1738 f = Fsum(name=self.name)
1739 return f._copy_0(*(s for s in reversed(self) if s))
1741 def is_exact(self):
1742 '''Is this L{Fsum2Tuple} considered to be exact? (C{bool}).
1743 '''
1744 return self.Fsum.is_exact()
1746 def is_integer(self):
1747 '''Is this L{Fsum2Tuple} C{integer}? (C{bool}).
1748 '''
1749 return self.Fsum.is_integer()
1752class ResidualError(_ValueError):
1753 '''Error raised for an operation involving a L{pygeodesy.sums.Fsum}
1754 instance with a non-zero C{residual}, I{integer} or otherwise.
1756 @see: Module L{pygeodesy.fsums} and method L{Fsum.RESIDUAL}.
1757 '''
1758 pass
1761try:
1762 from math import fsum as _fsum # precision IEEE-754 sum, Python 2.6+
1764 # make sure _fsum works as expected (XXX check
1765 # float.__getformat__('float')[:4] == 'IEEE'?)
1766 if _fsum((1, 1e101, 1, -1e101)) != 2: # PYCHOK no cover
1767 del _fsum # nope, remove _fsum ...
1768 raise ImportError # ... use _fsum below
1770 Fsum._math_fsum = _fsum
1772 if _getenv('PYGEODESY_FSUM_PARTIALS', _fsum.__name__) == _fsum.__name__:
1773 _psum = _fsum # PYCHOK redef
1775except ImportError:
1777 def _fsum(xs):
1778 '''(INTERNAL) Precision summation, Python 2.5-.
1779 '''
1780 return Fsum(name=_fsum.__name__)._facc(xs, up=False)._fprs
1783def fsum(xs, floats=False):
1784 '''Precision floating point summation based on or like Python's C{math.fsum}.
1786 @arg xs: Iterable, list, tuple, etc. of values (C{scalar} or
1787 L{Fsum} instances).
1788 @kwarg floats: Optionally, set C{B{floats}=True} iff I{all}
1789 B{C{xs}} are known to be C{float}.
1791 @return: Precision C{fsum} (C{float}).
1793 @raise OverflowError: Partial C{2sum} overflow.
1795 @raise TypeError: Non-scalar B{C{xs}} value.
1797 @raise ValueError: Invalid or non-finite B{C{xs}} value.
1799 @note: Exceptions and I{non-finite} handling may differ if not
1800 based on Python's C{math.fsum}.
1802 @see: Class L{Fsum} and methods L{Fsum.fsum} and L{Fsum.fadd}.
1803 '''
1804 return _fsum(_2floats(xs, floats=floats)) if xs else _0_0
1807def fsum_(*xs, **floats):
1808 '''Precision floating point summation of all positional arguments.
1810 @arg xs: Values to be added (C{scalar} or L{Fsum} instances),
1811 all positional.
1812 @kwarg floats: Optionally, set C{B{floats}=True} iff I{all}
1813 B{C{xs}} are known to be C{float}.
1815 @return: Precision C{fsum} (C{float}).
1817 @see: Function C{fsum}.
1818 '''
1819 if xs:
1820 f = _xkwds_get(floats, floats=False)
1821 return _fsum(_2floats(xs, origin=1, floats=f))
1822 else: # PYCHOK no cover
1823 return _0_0
1826def fsum1(xs, floats=False):
1827 '''Precision floating point summation of a few values, 1-primed.
1829 @arg xs: Iterable, list, tuple, etc. of values (C{scalar} or
1830 L{Fsum} instances).
1831 @kwarg floats: Optionally, set C{B{floats}=True} iff I{all}
1832 B{C{xs}} are known to be C{float}.
1834 @return: Precision C{fsum} (C{float}).
1836 @see: Function C{fsum}.
1837 '''
1838 return _fsum(_2floats(xs, primed=True, floats=floats)) if xs else _0_0
1841def fsum1_(*xs, **floats):
1842 '''Precision floating point summation of a few arguments, 1-primed.
1844 @arg xs: Values to be added (C{scalar} or L{Fsum} instances),
1845 all positional.
1846 @kwarg floats: Optionally, set C{B{floats}=True} iff I{all}
1847 B{C{xs}} are known to be C{float}.
1849 @return: Precision C{fsum} (C{float}).
1851 @see: Function C{fsum}
1852 '''
1853 if xs:
1854 f = _xkwds_get(floats, floats=False)
1855 return _fsum(_2floats(xs, origin=1, primed=True, floats=f))
1856 else: # PYCHOK no cover
1857 return _0_0
1859# **) MIT License
1860#
1861# Copyright (C) 2016-2023 -- mrJean1 at Gmail -- All Rights Reserved.
1862#
1863# Permission is hereby granted, free of charge, to any person obtaining a
1864# copy of this software and associated documentation files (the "Software"),
1865# to deal in the Software without restriction, including without limitation
1866# the rights to use, copy, modify, merge, publish, distribute, sublicense,
1867# and/or sell copies of the Software, and to permit persons to whom the
1868# Software is furnished to do so, subject to the following conditions:
1869#
1870# The above copyright notice and this permission notice shall be included
1871# in all copies or substantial portions of the Software.
1872#
1873# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
1874# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
1875# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
1876# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
1877# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
1878# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
1879# OTHER DEALINGS IN THE SOFTWARE.