office-gobmx/sal/rtl/source/math.cxx

1248 lines
39 KiB
C++

/*************************************************************************
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* Copyright 2008 by Sun Microsystems, Inc.
*
* OpenOffice.org - a multi-platform office productivity suite
*
* $RCSfile: math.cxx,v $
* $Revision: 1.14 $
*
* This file is part of OpenOffice.org.
*
* OpenOffice.org is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 3
* only, as published by the Free Software Foundation.
*
* OpenOffice.org is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License version 3 for more details
* (a copy is included in the LICENSE file that accompanied this code).
*
* You should have received a copy of the GNU Lesser General Public License
* version 3 along with OpenOffice.org. If not, see
* <http://www.openoffice.org/license.html>
* for a copy of the LGPLv3 License.
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************************************************************************/
// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_sal.hxx"
#include "rtl/math.h"
#include "osl/diagnose.h"
#include "rtl/alloc.h"
#include "rtl/math.hxx"
#include "rtl/strbuf.h"
#include "rtl/string.h"
#include "rtl/ustrbuf.h"
#include "rtl/ustring.h"
#include "sal/mathconf.h"
#include "sal/types.h"
#include <algorithm>
#include <float.h>
#include <limits.h>
#include <math.h>
#include <stdlib.h>
static int const n10Count = 16;
static double const n10s[2][n10Count] = {
{ 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8,
1e9, 1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16 },
{ 1e-1, 1e-2, 1e-3, 1e-4, 1e-5, 1e-6, 1e-7, 1e-8,
1e-9, 1e-10, 1e-11, 1e-12, 1e-13, 1e-14, 1e-15, 1e-16 }
};
// return pow(10.0,nExp) optimized for exponents in the interval [-16,16]
static double getN10Exp( int nExp )
{
if ( nExp < 0 )
{
if ( -nExp <= n10Count )
return n10s[1][-nExp-1];
else
return pow( 10.0, static_cast<double>( nExp ) );
}
else if ( nExp > 0 )
{
if ( nExp <= n10Count )
return n10s[0][nExp-1];
else
return pow( 10.0, static_cast<double>( nExp ) );
}
else // ( nExp == 0 )
return 1.0;
}
/** Approximation algorithm for erf for 0 < x < 0.65. */
void lcl_Erf0065( double x, double& fVal )
{
static const double pn[] = {
1.12837916709551256,
1.35894887627277916E-1,
4.03259488531795274E-2,
1.20339380863079457E-3,
6.49254556481904354E-5
};
static const double qn[] = {
1.00000000000000000,
4.53767041780002545E-1,
8.69936222615385890E-2,
8.49717371168693357E-3,
3.64915280629351082E-4
};
double fPSum = 0.0;
double fQSum = 0.0;
double fXPow = 1.0;
for ( unsigned int i = 0; i <= 4; ++i )
{
fPSum += pn[i]*fXPow;
fQSum += qn[i]*fXPow;
fXPow *= x*x;
}
fVal = x * fPSum / fQSum;
}
/** Approximation algorithm for erfc for 0.65 < x < 6.0. */
void lcl_Erfc0600( double x, double& fVal )
{
double fPSum = 0.0;
double fQSum = 0.0;
double fXPow = 1.0;
const double *pn;
const double *qn;
if ( x < 2.2 )
{
static const double pn22[] = {
9.99999992049799098E-1,
1.33154163936765307,
8.78115804155881782E-1,
3.31899559578213215E-1,
7.14193832506776067E-2,
7.06940843763253131E-3
};
static const double qn22[] = {
1.00000000000000000,
2.45992070144245533,
2.65383972869775752,
1.61876655543871376,
5.94651311286481502E-1,
1.26579413030177940E-1,
1.25304936549413393E-2
};
pn = pn22;
qn = qn22;
}
else /* if ( x < 6.0 ) this is true, but the compiler does not know */
{
static const double pn60[] = {
9.99921140009714409E-1,
1.62356584489366647,
1.26739901455873222,
5.81528574177741135E-1,
1.57289620742838702E-1,
2.25716982919217555E-2
};
static const double qn60[] = {
1.00000000000000000,
2.75143870676376208,
3.37367334657284535,
2.38574194785344389,
1.05074004614827206,
2.78788439273628983E-1,
4.00072964526861362E-2
};
pn = pn60;
qn = qn60;
}
for ( unsigned int i = 0; i < 6; ++i )
{
fPSum += pn[i]*fXPow;
fQSum += qn[i]*fXPow;
fXPow *= x;
}
fQSum += qn[6]*fXPow;
fVal = exp( -1.0*x*x )* fPSum / fQSum;
}
/** Approximation algorithm for erfc for 6.0 < x < 26.54 (but used for all
x > 6.0). */
void lcl_Erfc2654( double x, double& fVal )
{
static const double pn[] = {
5.64189583547756078E-1,
8.80253746105525775,
3.84683103716117320E1,
4.77209965874436377E1,
8.08040729052301677
};
static const double qn[] = {
1.00000000000000000,
1.61020914205869003E1,
7.54843505665954743E1,
1.12123870801026015E2,
3.73997570145040850E1
};
double fPSum = 0.0;
double fQSum = 0.0;
double fXPow = 1.0;
for ( unsigned int i = 0; i <= 4; ++i )
{
fPSum += pn[i]*fXPow;
fQSum += qn[i]*fXPow;
fXPow /= x*x;
}
fVal = exp(-1.0*x*x)*fPSum / (x*fQSum);
}
namespace {
double const nKorrVal[] = {
0, 9e-1, 9e-2, 9e-3, 9e-4, 9e-5, 9e-6, 9e-7, 9e-8,
9e-9, 9e-10, 9e-11, 9e-12, 9e-13, 9e-14, 9e-15
};
struct StringTraits
{
typedef sal_Char Char;
typedef rtl_String String;
static inline void createString(rtl_String ** pString,
sal_Char const * pChars, sal_Int32 nLen)
{
rtl_string_newFromStr_WithLength(pString, pChars, nLen);
}
static inline void createBuffer(rtl_String ** pBuffer,
sal_Int32 * pCapacity)
{
rtl_string_new_WithLength(pBuffer, *pCapacity);
}
static inline void appendChar(rtl_String ** pBuffer, sal_Int32 * pCapacity,
sal_Int32 * pOffset, sal_Char cChar)
{
rtl_stringbuffer_insert(pBuffer, pCapacity, *pOffset, &cChar, 1);
++*pOffset;
}
static inline void appendChars(rtl_String ** pBuffer, sal_Int32 * pCapacity,
sal_Int32 * pOffset, sal_Char const * pChars,
sal_Int32 nLen)
{
rtl_stringbuffer_insert(pBuffer, pCapacity, *pOffset, pChars, nLen);
*pOffset += nLen;
}
static inline void appendAscii(rtl_String ** pBuffer, sal_Int32 * pCapacity,
sal_Int32 * pOffset, sal_Char const * pStr,
sal_Int32 nLen)
{
rtl_stringbuffer_insert(pBuffer, pCapacity, *pOffset, pStr, nLen);
*pOffset += nLen;
}
};
struct UStringTraits
{
typedef sal_Unicode Char;
typedef rtl_uString String;
static inline void createString(rtl_uString ** pString,
sal_Unicode const * pChars, sal_Int32 nLen)
{
rtl_uString_newFromStr_WithLength(pString, pChars, nLen);
}
static inline void createBuffer(rtl_uString ** pBuffer,
sal_Int32 * pCapacity)
{
rtl_uString_new_WithLength(pBuffer, *pCapacity);
}
static inline void appendChar(rtl_uString ** pBuffer, sal_Int32 * pCapacity,
sal_Int32 * pOffset, sal_Unicode cChar)
{
rtl_uStringbuffer_insert(pBuffer, pCapacity, *pOffset, &cChar, 1);
++*pOffset;
}
static inline void appendChars(rtl_uString ** pBuffer,
sal_Int32 * pCapacity, sal_Int32 * pOffset,
sal_Unicode const * pChars, sal_Int32 nLen)
{
rtl_uStringbuffer_insert(pBuffer, pCapacity, *pOffset, pChars, nLen);
*pOffset += nLen;
}
static inline void appendAscii(rtl_uString ** pBuffer,
sal_Int32 * pCapacity, sal_Int32 * pOffset,
sal_Char const * pStr, sal_Int32 nLen)
{
rtl_uStringbuffer_insert_ascii(pBuffer, pCapacity, *pOffset, pStr,
nLen);
*pOffset += nLen;
}
};
// Solaris C++ 5.2 compiler has problems when "StringT ** pResult" is
// "typename T::String ** pResult" instead:
template< typename T, typename StringT >
inline void doubleToString(StringT ** pResult,
sal_Int32 * pResultCapacity, sal_Int32 nResultOffset,
double fValue, rtl_math_StringFormat eFormat,
sal_Int32 nDecPlaces, typename T::Char cDecSeparator,
sal_Int32 const * pGroups,
typename T::Char cGroupSeparator,
bool bEraseTrailingDecZeros)
{
static double const nRoundVal[] = {
5.0e+0, 0.5e+0, 0.5e-1, 0.5e-2, 0.5e-3, 0.5e-4, 0.5e-5, 0.5e-6,
0.5e-7, 0.5e-8, 0.5e-9, 0.5e-10,0.5e-11,0.5e-12,0.5e-13,0.5e-14
};
// sign adjustment, instead of testing for fValue<0.0 this will also fetch
// -0.0
bool bSign = rtl::math::isSignBitSet( fValue );
if( bSign )
fValue = -fValue;
if ( rtl::math::isNan( fValue ) )
{
sal_Int32 nCapacity = RTL_CONSTASCII_LENGTH("-1.#NAN");
if (pResultCapacity == 0)
{
pResultCapacity = &nCapacity;
T::createBuffer(pResult, pResultCapacity);
nResultOffset = 0;
}
if ( bSign )
T::appendAscii(pResult, pResultCapacity, &nResultOffset,
RTL_CONSTASCII_STRINGPARAM("-"));
T::appendAscii(pResult, pResultCapacity, &nResultOffset,
RTL_CONSTASCII_STRINGPARAM("1"));
T::appendChar(pResult, pResultCapacity, &nResultOffset, cDecSeparator);
T::appendAscii(pResult, pResultCapacity, &nResultOffset,
RTL_CONSTASCII_STRINGPARAM("#NAN"));
return;
}
bool bHuge = fValue == HUGE_VAL; // g++ 3.0.1 requires it this way...
if ( bHuge || rtl::math::isInf( fValue ) )
{
sal_Int32 nCapacity = RTL_CONSTASCII_LENGTH("-1.#INF");
if (pResultCapacity == 0)
{
pResultCapacity = &nCapacity;
T::createBuffer(pResult, pResultCapacity);
nResultOffset = 0;
}
if ( bSign )
T::appendAscii(pResult, pResultCapacity, &nResultOffset,
RTL_CONSTASCII_STRINGPARAM("-"));
T::appendAscii(pResult, pResultCapacity, &nResultOffset,
RTL_CONSTASCII_STRINGPARAM("1"));
T::appendChar(pResult, pResultCapacity, &nResultOffset, cDecSeparator);
T::appendAscii(pResult, pResultCapacity, &nResultOffset,
RTL_CONSTASCII_STRINGPARAM("#INF"));
return;
}
// find the exponent
int nExp = 0;
if ( fValue > 0.0 )
{
nExp = static_cast< int >( floor( log10( fValue ) ) );
fValue /= getN10Exp( nExp );
}
switch ( eFormat )
{
case rtl_math_StringFormat_Automatic :
{ // E or F depending on exponent magnitude
int nPrec;
if ( nExp <= -15 || nExp >= 15 ) // #58531# was <-16, >16
{
nPrec = 14;
eFormat = rtl_math_StringFormat_E;
}
else
{
if ( nExp < 14 )
{
nPrec = 15 - nExp - 1;
eFormat = rtl_math_StringFormat_F;
}
else
{
nPrec = 15;
eFormat = rtl_math_StringFormat_F;
}
}
if ( nDecPlaces == rtl_math_DecimalPlaces_Max )
nDecPlaces = nPrec;
}
break;
case rtl_math_StringFormat_G :
{ // G-Point, similar to sprintf %G
if ( nDecPlaces == rtl_math_DecimalPlaces_DefaultSignificance )
nDecPlaces = 6;
if ( nExp < -4 || nExp >= nDecPlaces )
{
nDecPlaces = std::max< sal_Int32 >( 1, nDecPlaces - 1 );
eFormat = rtl_math_StringFormat_E;
}
else
{
nDecPlaces = std::max< sal_Int32 >( 0, nDecPlaces - nExp - 1 );
eFormat = rtl_math_StringFormat_F;
}
}
break;
default:
break;
}
sal_Int32 nDigits = nDecPlaces + 1;
if( eFormat == rtl_math_StringFormat_F )
nDigits += nExp;
// Round the number
if( nDigits >= 0 )
{
if( ( fValue += nRoundVal[ nDigits > 15 ? 15 : nDigits ] ) >= 10 )
{
fValue = 1.0;
nExp++;
if( eFormat == rtl_math_StringFormat_F )
nDigits++;
}
}
static sal_Int32 const nBufMax = 256;
typename T::Char aBuf[nBufMax];
typename T::Char * pBuf;
sal_Int32 nBuf = static_cast< sal_Int32 >
( nDigits <= 0 ? std::max< sal_Int32 >( nDecPlaces, abs(nExp) )
: nDigits + nDecPlaces ) + 10 + (pGroups ? abs(nDigits) * 2 : 0);
if ( nBuf > nBufMax )
{
pBuf = reinterpret_cast< typename T::Char * >(
rtl_allocateMemory(nBuf * sizeof (typename T::Char)));
OSL_ENSURE(pBuf != 0, "Out of memory");
}
else
pBuf = aBuf;
typename T::Char * p = pBuf;
if ( bSign )
*p++ = static_cast< typename T::Char >('-');
bool bHasDec = false;
int nDecPos;
// Check for F format and number < 1
if( eFormat == rtl_math_StringFormat_F )
{
if( nExp < 0 )
{
*p++ = static_cast< typename T::Char >('0');
if ( nDecPlaces > 0 )
{
*p++ = cDecSeparator;
bHasDec = true;
}
sal_Int32 i = ( nDigits <= 0 ? nDecPlaces : -nExp - 1 );
while( (i--) > 0 )
*p++ = static_cast< typename T::Char >('0');
nDecPos = 0;
}
else
nDecPos = nExp + 1;
}
else
nDecPos = 1;
int nGrouping = 0, nGroupSelector = 0, nGroupExceed = 0;
if ( nDecPos > 1 && pGroups && pGroups[0] && cGroupSeparator )
{
while ( nGrouping + pGroups[nGroupSelector] < nDecPos )
{
nGrouping += pGroups[ nGroupSelector ];
if ( pGroups[nGroupSelector+1] )
{
if ( nGrouping + pGroups[nGroupSelector+1] >= nDecPos )
break; // while
++nGroupSelector;
}
else if ( !nGroupExceed )
nGroupExceed = nGrouping;
}
}
// print the number
if( nDigits > 0 )
{
for ( int i = 0; ; i++ )
{
if( i < 15 )
{
int nDigit;
if (nDigits-1 == 0 && i > 0 && i < 14)
nDigit = static_cast< int >( floor( fValue
+ nKorrVal[15-i] ) );
else
nDigit = static_cast< int >( fValue + 1E-15 );
if (nDigit >= 10)
{ // after-treatment of up-rounding to the next decade
sal_Int32 sLen = static_cast< long >(p-pBuf)-1;
if (sLen == -1)
{
p = pBuf;
if ( eFormat == rtl_math_StringFormat_F )
{
*p++ = static_cast< typename T::Char >('1');
*p++ = static_cast< typename T::Char >('0');
}
else
{
*p++ = static_cast< typename T::Char >('1');
*p++ = cDecSeparator;
*p++ = static_cast< typename T::Char >('0');
nExp++;
bHasDec = true;
}
}
else
{
for (sal_Int32 j = sLen; j >= 0; j--)
{
typename T::Char cS = pBuf[j];
if (cS != cDecSeparator)
{
if ( cS != static_cast< typename T::Char >('9'))
{
pBuf[j] = ++cS;
j = -1; // break loop
}
else
{
pBuf[j]
= static_cast< typename T::Char >('0');
if (j == 0)
{
if ( eFormat == rtl_math_StringFormat_F)
{ // insert '1'
typename T::Char * px = p++;
while ( pBuf < px )
{
*px = *(px-1);
px--;
}
pBuf[0] = static_cast<
typename T::Char >('1');
}
else
{
pBuf[j] = static_cast<
typename T::Char >('1');
nExp++;
}
}
}
}
}
*p++ = static_cast< typename T::Char >('0');
}
fValue = 0.0;
}
else
{
*p++ = static_cast< typename T::Char >(
nDigit + static_cast< typename T::Char >('0') );
fValue = ( fValue - nDigit ) * 10.0;
}
}
else
*p++ = static_cast< typename T::Char >('0');
if( !--nDigits )
break; // for
if( nDecPos )
{
if( !--nDecPos )
{
*p++ = cDecSeparator;
bHasDec = true;
}
else if ( nDecPos == nGrouping )
{
*p++ = cGroupSeparator;
nGrouping -= pGroups[ nGroupSelector ];
if ( nGroupSelector && nGrouping < nGroupExceed )
--nGroupSelector;
}
}
}
}
if ( !bHasDec && eFormat == rtl_math_StringFormat_F )
{ // nDecPlaces < 0 did round the value
while ( --nDecPos > 0 )
{ // fill before decimal point
if ( nDecPos == nGrouping )
{
*p++ = cGroupSeparator;
nGrouping -= pGroups[ nGroupSelector ];
if ( nGroupSelector && nGrouping < nGroupExceed )
--nGroupSelector;
}
*p++ = static_cast< typename T::Char >('0');
}
}
if ( bEraseTrailingDecZeros && bHasDec && p > pBuf )
{
while ( *(p-1) == static_cast< typename T::Char >('0') )
p--;
if ( *(p-1) == cDecSeparator )
p--;
}
// Print the exponent ('E', followed by '+' or '-', followed by exactly
// three digits). The code in rtl_[u]str_valueOf{Float|Double} relies on
// this format.
if( eFormat == rtl_math_StringFormat_E )
{
if ( p == pBuf )
*p++ = static_cast< typename T::Char >('1');
// maybe no nDigits if nDecPlaces < 0
*p++ = static_cast< typename T::Char >('E');
if( nExp < 0 )
{
nExp = -nExp;
*p++ = static_cast< typename T::Char >('-');
}
else
*p++ = static_cast< typename T::Char >('+');
// if (nExp >= 100 )
*p++ = static_cast< typename T::Char >(
nExp / 100 + static_cast< typename T::Char >('0') );
nExp %= 100;
*p++ = static_cast< typename T::Char >(
nExp / 10 + static_cast< typename T::Char >('0') );
*p++ = static_cast< typename T::Char >(
nExp % 10 + static_cast< typename T::Char >('0') );
}
if (pResultCapacity == 0)
T::createString(pResult, pBuf, p - pBuf);
else
T::appendChars(pResult, pResultCapacity, &nResultOffset, pBuf,
p - pBuf);
if ( pBuf != &aBuf[0] )
rtl_freeMemory(pBuf);
}
}
void SAL_CALL rtl_math_doubleToString(rtl_String ** pResult,
sal_Int32 * pResultCapacity,
sal_Int32 nResultOffset, double fValue,
rtl_math_StringFormat eFormat,
sal_Int32 nDecPlaces,
sal_Char cDecSeparator,
sal_Int32 const * pGroups,
sal_Char cGroupSeparator,
sal_Bool bEraseTrailingDecZeros)
SAL_THROW_EXTERN_C()
{
doubleToString< StringTraits, StringTraits::String >(
pResult, pResultCapacity, nResultOffset, fValue, eFormat, nDecPlaces,
cDecSeparator, pGroups, cGroupSeparator, bEraseTrailingDecZeros);
}
void SAL_CALL rtl_math_doubleToUString(rtl_uString ** pResult,
sal_Int32 * pResultCapacity,
sal_Int32 nResultOffset, double fValue,
rtl_math_StringFormat eFormat,
sal_Int32 nDecPlaces,
sal_Unicode cDecSeparator,
sal_Int32 const * pGroups,
sal_Unicode cGroupSeparator,
sal_Bool bEraseTrailingDecZeros)
SAL_THROW_EXTERN_C()
{
doubleToString< UStringTraits, UStringTraits::String >(
pResult, pResultCapacity, nResultOffset, fValue, eFormat, nDecPlaces,
cDecSeparator, pGroups, cGroupSeparator, bEraseTrailingDecZeros);
}
namespace {
// if nExp * 10 + nAdd would result in overflow
inline bool long10Overflow( long& nExp, int nAdd )
{
if ( nExp > (LONG_MAX/10)
|| (nExp == (LONG_MAX/10) && nAdd > (LONG_MAX%10)) )
{
nExp = LONG_MAX;
return true;
}
return false;
}
// We are only concerned about ASCII arabic numerical digits here
template< typename CharT >
inline bool isDigit( CharT c )
{
return 0x30 <= c && c <= 0x39;
}
template< typename CharT >
inline double stringToDouble(CharT const * pBegin, CharT const * pEnd,
CharT cDecSeparator, CharT cGroupSeparator,
rtl_math_ConversionStatus * pStatus,
CharT const ** pParsedEnd)
{
double fVal = 0.0;
rtl_math_ConversionStatus eStatus = rtl_math_ConversionStatus_Ok;
CharT const * p0 = pBegin;
while (p0 != pEnd && (*p0 == CharT(' ') || *p0 == CharT('\t')))
++p0;
bool bSign;
if (p0 != pEnd && *p0 == CharT('-'))
{
bSign = true;
++p0;
}
else
{
bSign = false;
if (p0 != pEnd && *p0 == CharT('+'))
++p0;
}
CharT const * p = p0;
// leading zeros and group separators may be safely ignored
while (p != pEnd && (*p == CharT('0') || *p == cGroupSeparator))
++p;
long nValExp = 0; // carry along exponent of mantissa
// integer part of mantissa
for (; p != pEnd; ++p)
{
CharT c = *p;
if (isDigit(c))
{
fVal = fVal * 10.0 + static_cast< double >( c - CharT('0') );
++nValExp;
}
else if (c != cGroupSeparator)
break;
}
// fraction part of mantissa
if (p != pEnd && *p == cDecSeparator)
{
++p;
double fFrac = 0.0;
long nFracExp = 0;
while (p != pEnd && *p == CharT('0'))
{
--nFracExp;
++p;
}
if ( nValExp == 0 )
nValExp = nFracExp - 1; // no integer part => fraction exponent
// one decimal digit needs ld(10) ~= 3.32 bits
static const int nSigs = (DBL_MANT_DIG / 3) + 1;
int nDigs = 0;
for (; p != pEnd; ++p)
{
CharT c = *p;
if (!isDigit(c))
break;
if ( nDigs < nSigs )
{ // further digits (more than nSigs) don't have any significance
fFrac = fFrac * 10.0 + static_cast< double >( c - CharT('0') );
--nFracExp;
++nDigs;
}
}
if ( fFrac != 0.0 )
fVal += rtl::math::pow10Exp( fFrac, nFracExp );
else if ( nValExp < 0 )
nValExp = 0; // no digit other than 0 after decimal point
}
if ( nValExp > 0 )
--nValExp; // started with offset +1 at the first mantissa digit
// Exponent
if (p != p0 && p != pEnd && (*p == CharT('E') || *p == CharT('e')))
{
++p;
bool bExpSign;
if (p != pEnd && *p == CharT('-'))
{
bExpSign = true;
++p;
}
else
{
bExpSign = false;
if (p != pEnd && *p == CharT('+'))
++p;
}
if ( fVal == 0.0 )
{ // no matter what follows, zero stays zero, but carry on the offset
while (p != pEnd && isDigit(*p))
++p;
}
else
{
bool bOverFlow = false;
long nExp = 0;
for (; p != pEnd; ++p)
{
CharT c = *p;
if (!isDigit(c))
break;
int i = c - CharT('0');
if ( long10Overflow( nExp, i ) )
bOverFlow = true;
else
nExp = nExp * 10 + i;
}
if ( nExp )
{
if ( bExpSign )
nExp = -nExp;
long nAllExp = ( bOverFlow ? 0 : nExp + nValExp );
if ( nAllExp > DBL_MAX_10_EXP || (bOverFlow && !bExpSign) )
{ // overflow
fVal = HUGE_VAL;
eStatus = rtl_math_ConversionStatus_OutOfRange;
}
else if ( nAllExp < DBL_MIN_10_EXP || (bOverFlow && bExpSign) )
{ // underflow
fVal = 0.0;
eStatus = rtl_math_ConversionStatus_OutOfRange;
}
else if ( nExp > DBL_MAX_10_EXP || nExp < DBL_MIN_10_EXP )
{ // compensate exponents
fVal = rtl::math::pow10Exp( fVal, -nValExp );
fVal = rtl::math::pow10Exp( fVal, nAllExp );
}
else
fVal = rtl::math::pow10Exp( fVal, nExp ); // normal
}
}
}
else if (p - p0 == 2 && p != pEnd && p[0] == CharT('#')
&& p[-1] == cDecSeparator && p[-2] == CharT('1'))
{
if (pEnd - p >= 4 && p[1] == CharT('I') && p[2] == CharT('N')
&& p[3] == CharT('F'))
{
// "1.#INF", "+1.#INF", "-1.#INF"
p += 4;
fVal = HUGE_VAL;
eStatus = rtl_math_ConversionStatus_OutOfRange;
// Eat any further digits:
while (p != pEnd && isDigit(*p))
++p;
}
else if (pEnd - p >= 4 && p[1] == CharT('N') && p[2] == CharT('A')
&& p[3] == CharT('N'))
{
// "1.#NAN", "+1.#NAN", "-1.#NAN"
p += 4;
rtl::math::setNan( &fVal );
if (bSign)
{
union {
double sd;
sal_math_Double md;
} m;
m.sd = fVal;
m.md.w32_parts.msw |= 0x80000000; // create negative NaN
fVal = m.sd;
bSign = false; // don't negate again
}
// Eat any further digits:
while (p != pEnd && isDigit(*p))
++p;
}
}
// overflow also if more than DBL_MAX_10_EXP digits without decimal
// separator, or 0. and more than DBL_MIN_10_EXP digits, ...
bool bHuge = fVal == HUGE_VAL; // g++ 3.0.1 requires it this way...
if ( bHuge )
eStatus = rtl_math_ConversionStatus_OutOfRange;
if ( bSign )
fVal = -fVal;
if (pStatus != 0)
*pStatus = eStatus;
if (pParsedEnd != 0)
*pParsedEnd = p;
return fVal;
}
}
double SAL_CALL rtl_math_stringToDouble(sal_Char const * pBegin,
sal_Char const * pEnd,
sal_Char cDecSeparator,
sal_Char cGroupSeparator,
rtl_math_ConversionStatus * pStatus,
sal_Char const ** pParsedEnd)
SAL_THROW_EXTERN_C()
{
return stringToDouble(pBegin, pEnd, cDecSeparator, cGroupSeparator, pStatus,
pParsedEnd);
}
double SAL_CALL rtl_math_uStringToDouble(sal_Unicode const * pBegin,
sal_Unicode const * pEnd,
sal_Unicode cDecSeparator,
sal_Unicode cGroupSeparator,
rtl_math_ConversionStatus * pStatus,
sal_Unicode const ** pParsedEnd)
SAL_THROW_EXTERN_C()
{
return stringToDouble(pBegin, pEnd, cDecSeparator, cGroupSeparator, pStatus,
pParsedEnd);
}
double SAL_CALL rtl_math_round(double fValue, int nDecPlaces,
enum rtl_math_RoundingMode eMode)
SAL_THROW_EXTERN_C()
{
OSL_ASSERT(nDecPlaces >= -20 && nDecPlaces <= 20);
if ( fValue == 0.0 )
return fValue;
// sign adjustment
bool bSign = rtl::math::isSignBitSet( fValue );
if ( bSign )
fValue = -fValue;
double fFac = 0;
if ( nDecPlaces != 0 )
{
// max 20 decimals, we don't have unlimited precision
// #38810# and no overflow on fValue*=fFac
if ( nDecPlaces < -20 || 20 < nDecPlaces || fValue > (DBL_MAX / 1e20) )
return bSign ? -fValue : fValue;
fFac = getN10Exp( nDecPlaces );
fValue *= fFac;
}
//else //! uninitialized fFac, not needed
switch ( eMode )
{
case rtl_math_RoundingMode_Corrected :
{
int nExp; // exponent for correction
if ( fValue > 0.0 )
nExp = static_cast<int>( floor( log10( fValue ) ) );
else
nExp = 0;
int nIndex = 15 - nExp;
if ( nIndex > 15 )
nIndex = 15;
else if ( nIndex <= 1 )
nIndex = 0;
fValue = floor( fValue + 0.5 + nKorrVal[nIndex] );
}
break;
case rtl_math_RoundingMode_Down :
fValue = rtl::math::approxFloor( fValue );
break;
case rtl_math_RoundingMode_Up :
fValue = rtl::math::approxCeil( fValue );
break;
case rtl_math_RoundingMode_Floor :
fValue = bSign ? rtl::math::approxCeil( fValue )
: rtl::math::approxFloor( fValue );
break;
case rtl_math_RoundingMode_Ceiling :
fValue = bSign ? rtl::math::approxFloor( fValue )
: rtl::math::approxCeil( fValue );
break;
case rtl_math_RoundingMode_HalfDown :
{
double f = floor( fValue );
fValue = ((fValue - f) <= 0.5) ? f : ceil( fValue );
}
break;
case rtl_math_RoundingMode_HalfUp :
{
double f = floor( fValue );
fValue = ((fValue - f) < 0.5) ? f : ceil( fValue );
}
break;
case rtl_math_RoundingMode_HalfEven :
#if defined FLT_ROUNDS
/*
Use fast version. FLT_ROUNDS may be defined to a function by some compilers!
DBL_EPSILON is the smallest fractional number which can be represented,
its reciprocal is therefore the smallest number that cannot have a
fractional part. Once you add this reciprocal to `x', its fractional part
is stripped off. Simply subtracting the reciprocal back out returns `x'
without its fractional component.
Simple, clever, and elegant - thanks to Ross Cottrell, the original author,
who placed it into public domain.
volatile: prevent compiler from being too smart
*/
if ( FLT_ROUNDS == 1 )
{
volatile double x = fValue + 1.0 / DBL_EPSILON;
fValue = x - 1.0 / DBL_EPSILON;
}
else
#endif // FLT_ROUNDS
{
double f = floor( fValue );
if ( (fValue - f) != 0.5 )
fValue = floor( fValue + 0.5 );
else
{
double g = f / 2.0;
fValue = (g == floor( g )) ? f : (f + 1.0);
}
}
break;
default:
OSL_ASSERT(false);
break;
}
if ( nDecPlaces != 0 )
fValue /= fFac;
return bSign ? -fValue : fValue;
}
double SAL_CALL rtl_math_pow10Exp(double fValue, int nExp) SAL_THROW_EXTERN_C()
{
return fValue * getN10Exp( nExp );
}
double SAL_CALL rtl_math_approxValue( double fValue ) SAL_THROW_EXTERN_C()
{
if (fValue == 0.0 || fValue == HUGE_VAL || !::rtl::math::isFinite( fValue))
// We don't handle these conditions. Bail out.
return fValue;
double fOrigValue = fValue;
bool bSign = ::rtl::math::isSignBitSet( fValue);
if (bSign)
fValue = -fValue;
int nExp = static_cast<int>( floor( log10( fValue)));
nExp = 14 - nExp;
double fExpValue = getN10Exp( nExp);
fValue *= fExpValue;
// If the original value was near DBL_MIN we got an overflow. Restore and
// bail out.
if (!rtl::math::isFinite( fValue))
return fOrigValue;
fValue = rtl_math_round( fValue, 0, rtl_math_RoundingMode_Corrected);
fValue /= fExpValue;
// If the original value was near DBL_MAX we got an overflow. Restore and
// bail out.
if (!rtl::math::isFinite( fValue))
return fOrigValue;
return bSign ? -fValue : fValue;
}
double SAL_CALL rtl_math_expm1( double fValue ) SAL_THROW_EXTERN_C()
{
double fe = exp( fValue );
if (fe == 1.0)
return fValue;
if (fe-1.0 == -1.0)
return -1.0;
return (fe-1.0) * fValue / log(fe);
}
double SAL_CALL rtl_math_log1p( double fValue ) SAL_THROW_EXTERN_C()
{
// Use volatile because a compiler may be too smart "optimizing" the
// condition such that in certain cases the else path was called even if
// (fp==1.0) was true, where the term (fp-1.0) then resulted in 0.0 and
// hence the entire expression resulted in NaN.
// Happened with g++ 3.4.1 and an input value of 9.87E-18
volatile double fp = 1.0 + fValue;
if (fp == 1.0)
return fValue;
else
return log(fp) * fValue / (fp-1.0);
}
double SAL_CALL rtl_math_atanh( double fValue ) SAL_THROW_EXTERN_C()
{
return 0.5 * rtl_math_log1p( 2.0 * fValue / (1.0-fValue) );
}
/** Parent error function (erf) that calls different algorithms based on the
value of x. It takes care of cases where x is negative as erf is an odd
function i.e. erf(-x) = -erf(x).
Kramer, W., and Blomquist, F., 2000, Algorithms with Guaranteed Error Bounds
for the Error Function and the Complementary Error Function
http://www.math.uni-wuppertal.de/wrswt/literatur_en.html
@author Kohei Yoshida <kohei@openoffice.org>
@see #i55735#
*/
double SAL_CALL rtl_math_erf( double x ) SAL_THROW_EXTERN_C()
{
if( x == 0.0 )
return 0.0;
bool bNegative = false;
if ( x < 0.0 )
{
x = fabs( x );
bNegative = true;
}
double fErf = 1.0;
if ( x < 1.0e-10 )
fErf = (double) (x*1.1283791670955125738961589031215452L);
else if ( x < 0.65 )
lcl_Erf0065( x, fErf );
else
fErf = 1.0 - rtl_math_erfc( x );
if ( bNegative )
fErf *= -1.0;
return fErf;
}
/** Parent complementary error function (erfc) that calls different algorithms
based on the value of x. It takes care of cases where x is negative as erfc
satisfies relationship erfc(-x) = 2 - erfc(x). See the comment for Erf(x)
for the source publication.
@author Kohei Yoshida <kohei@openoffice.org>
@see #i55735#, moved from module scaddins (#i97091#)
*/
double SAL_CALL rtl_math_erfc( double x ) SAL_THROW_EXTERN_C()
{
if ( x == 0.0 )
return 1.0;
bool bNegative = false;
if ( x < 0.0 )
{
x = fabs( x );
bNegative = true;
}
double fErfc = 0.0;
if ( x >= 0.65 )
{
if ( x < 6.0 )
lcl_Erfc0600( x, fErfc );
else
lcl_Erfc2654( x, fErfc );
}
else
fErfc = 1.0 - rtl_math_erf( x );
if ( bNegative )
fErfc = 2.0 - fErfc;
return fErfc;
}
/** improved accuracy of asinh for |x| large and for x near zero
@see #i97605#
*/
double SAL_CALL rtl_math_asinh( double fX ) SAL_THROW_EXTERN_C()
{
double fSign = 1.0;
if ( fX == 0.0 )
return 0.0;
else
{
if ( fX < 0.0 )
{
fX = - fX;
fSign = -1.0;
}
if ( fX < 0.125 )
return fSign * rtl_math_log1p( fX + fX*fX / (1.0 + sqrt( 1.0 + fX*fX)));
else if ( fX < 1.25e7 )
return fSign * log( fX + sqrt( 1.0 + fX*fX));
else
return fSign * log( 2.0*fX);
}
}
/** improved accuracy of acosh for x large and for x near 1
@see #i97605#
*/
double SAL_CALL rtl_math_acosh( double fX ) SAL_THROW_EXTERN_C()
{
volatile double fZ = fX - 1.0;
if ( fX < 1.0 )
{
double fResult;
::rtl::math::setNan( &fResult );
return fResult;
}
else if ( fX == 1.0 )
return 0.0;
else if ( fX < 1.1 )
return rtl_math_log1p( fZ + sqrt( fZ*fZ + 2.0*fZ));
else if ( fX < 1.25e7 )
return log( fX + sqrt( fX*fX - 1.0));
else
return log( 2.0*fX);
}