LibreOffice Module sc (master)  1
math.cxx
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1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
2 /*
3  * This file is part of the LibreOffice project.
4  *
5  * This Source Code Form is subject to the terms of the Mozilla Public
6  * License, v. 2.0. If a copy of the MPL was not distributed with this
7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
8  */
9 
10 #include <math.hxx>
11 #include <cmath>
12 #include <cerrno>
13 #include <cfenv>
14 
16 #include <rtl/math.hxx>
17 
18 namespace sc
19 {
20 static double err_pow(const double& fVal1, const double& fVal2)
21 {
22  // pow() is expected to set domain error or pole error or range error (or
23  // flag them via exceptions) or return NaN or Inf.
24  assert((math_errhandling & (MATH_ERRNO | MATH_ERREXCEPT)) != 0);
25  std::feclearexcept(FE_ALL_EXCEPT);
26  errno = 0;
27  return pow(fVal1, fVal2);
28 }
29 
30 double power(const double& fVal1, const double& fVal2)
31 {
32  double fPow;
33  if (fVal1 < 0 && fVal2 != 0.0)
34  {
35  const double f = 1.0 / fVal2 + ((fVal2 < 0.0) ? -0.5 : 0.5);
38  {
39  // Casting to int would be undefined behaviour.
40  fPow = err_pow(fVal1, fVal2);
41  }
42  else
43  {
44  const sal_Int64 i = static_cast<sal_Int64>(f);
45  if (i % 2 != 0 && rtl::math::approxEqual(1 / static_cast<double>(i), fVal2))
46  fPow = -err_pow(-fVal1, fVal2);
47  else
48  fPow = err_pow(fVal1, fVal2);
49  }
50  }
51  else
52  {
53  fPow = err_pow(fVal1, fVal2);
54  }
55  // The pow() call must had been the most recent call to check errno or exception.
56  if ((((math_errhandling & MATH_ERRNO) != 0) && (errno == EDOM || errno == ERANGE))
57 // emscripten is currently broken by https://github.com/emscripten-core/emscripten/pull/11087
58 // While the removal is correct for C99, it's not for C++11 (see http://www.cplusplus.com/reference/cfenv/FE_INEXACT/)
59 // But since emscripten currently doesn't support any math exceptions, we simply ignore them
60 #ifndef __EMSCRIPTEN__
61  || (((math_errhandling & MATH_ERREXCEPT) != 0)
62  && std::fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW))
63 #endif
64  || !std::isfinite(fPow))
65  {
66  fPow = CreateDoubleError(FormulaError::IllegalFPOperation);
67  }
68  return fPow;
69 }
70 }
71 
72 /* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */
constexpr std::enable_if_t< std::is_floating_point_v< F > &&std::is_integral_v< I >, bool > convertsToAtLeast(F value, I min)
#define SAL_MIN_INT64
constexpr std::enable_if_t< std::is_floating_point_v< F > &&std::is_integral_v< I >, bool > convertsToAtMost(F value, I max)
int i
CAUTION! The following defines must be in the same namespace as the respective type.
static double err_pow(const double &fVal1, const double &fVal2)
Definition: math.cxx:20
double power(const double &fVal1, const double &fVal2)
Return pow(fVal1,fVal2) with error handling.
Definition: math.cxx:30
double CreateDoubleError(FormulaError nErr)
void(* f)(TrueTypeTable *)
#define SAL_MAX_INT64