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Diffstat (limited to 'include/rtl/math.h')
| -rw-r--r-- | include/rtl/math.h | 475 |
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diff --git a/include/rtl/math.h b/include/rtl/math.h new file mode 100644 index 000000000000..ebe0a84003bd --- /dev/null +++ b/include/rtl/math.h @@ -0,0 +1,475 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of the LibreOffice project. + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + * + * This file incorporates work covered by the following license notice: + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed + * with this work for additional information regarding copyright + * ownership. The ASF licenses this file to you under the Apache + * License, Version 2.0 (the "License"); you may not use this file + * except in compliance with the License. You may obtain a copy of + * the License at http://www.apache.org/licenses/LICENSE-2.0 . + */ + +#ifndef INCLUDED_RTL_MATH_H +#define INCLUDED_RTL_MATH_H + +#include "sal/config.h" + +#include "rtl/ustring.h" +#include "sal/saldllapi.h" +#include "sal/types.h" + +#if defined __cplusplus +extern "C" { +#endif /* __cplusplus */ + +/** Formatting modes for rtl_math_doubleToString and rtl_math_doubleToUString + and rtl_math_doubleToUStringBuffer. + */ +enum rtl_math_StringFormat +{ + /** Like sprintf() %E. + */ + rtl_math_StringFormat_E, + + /** Like sprintf() %f. + */ + rtl_math_StringFormat_F, + + /** Like sprintf() %G, 'F' or 'E' format is used depending on which one is + more compact. + */ + rtl_math_StringFormat_G, + + /** Automatic, 'F' or 'E' format is used depending on the numeric value to + be formatted. + */ + rtl_math_StringFormat_Automatic, + + /** @cond INTERNAL */ + rtl_math_StringFormat_FORCE_EQUAL_SIZE = SAL_MAX_ENUM + /** @endcond */ +}; + +/** Status for rtl_math_stringToDouble and rtl_math_uStringToDouble. + */ +enum rtl_math_ConversionStatus +{ + /** Conversion was successful. + */ + rtl_math_ConversionStatus_Ok, + + /** Conversion caused overflow or underflow. + */ + rtl_math_ConversionStatus_OutOfRange, + + /** @cond INTERNAL */ + rtl_math_ConversionStatus_FORCE_EQUAL_SIZE = SAL_MAX_ENUM + /** @endcond */ +}; + +/** Rounding modes for rtl_math_round. + */ +enum rtl_math_RoundingMode +{ + /** Like HalfUp, but corrects roundoff errors, preferred. + */ + rtl_math_RoundingMode_Corrected, + + /** Floor of absolute value, signed return (commercial). + */ + rtl_math_RoundingMode_Down, + + /** Ceil of absolute value, signed return (commercial). + */ + rtl_math_RoundingMode_Up, + + /** Floor of signed value. + */ + rtl_math_RoundingMode_Floor, + + /** Ceil of signed value. + */ + rtl_math_RoundingMode_Ceiling, + + /** Frac <= 0.5 ? floor of abs : ceil of abs, signed return. + */ + rtl_math_RoundingMode_HalfDown, + + /** Frac < 0.5 ? floor of abs : ceil of abs, signed return (mathematical). + */ + rtl_math_RoundingMode_HalfUp, + + /** IEEE rounding mode (statistical). + */ + rtl_math_RoundingMode_HalfEven, + + /** @cond INTERNAL */ + rtl_math_RoundingMode_FORCE_EQUAL_SIZE = SAL_MAX_ENUM + /** @endcond */ +}; + +/** Special decimal places constants for rtl_math_doubleToString and + rtl_math_doubleToUString and rtl_math_doubleToUStringBuffer. + */ +enum rtl_math_DecimalPlaces +{ + /** Value to be used with rtl_math_StringFormat_Automatic. + */ + rtl_math_DecimalPlaces_Max = 0x7ffffff, + + /** Value to be used with rtl_math_StringFormat_G. + In fact the same value as rtl_math_DecimalPlaces_Max, just an alias for + better understanding. + */ + rtl_math_DecimalPlaces_DefaultSignificance = rtl_math_DecimalPlaces_Max +}; + + +/** Conversions analogous to sprintf() using internal rounding. + + +/-HUGE_VAL are converted to "INF" and "-INF", NAN values are + converted to "NaN". + + @param pResult + Returns the resulting byte string. Must itself not be null, and must point + to either null or a valid string. + + @param pResultCapacity + If null, pResult is considered to point to immutable strings, and a new + string will be allocated in pResult. + If non-null, it points to the current capacity of pResult, which is + considered to point to a string buffer (pResult must not itself be null in + this case, and must point to a string that has room for the given capacity). + The string representation of the given double value is inserted into pResult + at position nResultOffset. If pResult's current capacity is too small, a + new string buffer will be allocated in pResult as necessary, and + pResultCapacity will contain the new capacity on return. + + @param nResultOffset + If pResult is used as a string buffer (i.e., pResultCapacity is non-null), + nResultOffset specifies the insertion offset within the buffer. Ignored + otherwise. + + @param fValue + The value to convert. + + @param eFormat + The format to use, one of rtl_math_StringFormat. + + @param nDecPlaces + The number of decimals to be generated. Effectively fValue is rounded at + this position, specifying nDecPlaces <= 0 accordingly rounds the value + before the decimal point and fills with zeros. + If eFormat == rtl_math_StringFormat_Automatic and nDecPlaces == + rtl_math_DecimalPlaces_Max, the highest number of significant decimals + possible is generated. + If eFormat == rtl_math_StringFormat_G, nDecPlaces specifies the number of + significant digits instead. If nDecPlaces == + rtl_math_DecimalPlaces_DefaultSignificance, the default number (currently 6 + as implemented by most libraries) of significant digits is generated. + According to the ANSI C90 standard the E style will be used only if the + exponent resulting from the conversion is less than -4 or greater than or + equal to the precision. However, as opposed to the ANSI standard, trailing + zeros are not necessarily removed from the fractional portion of the result + unless bEraseTrailingDecZeros == true was specified. + + @param cDecSeparator + The decimal separator. + + @param pGroups + Either null (no grouping is used), or a null-terminated list of group + lengths. Each group length must be strictly positive. If the number of + digits in a conversion exceeds the specified range, the last (highest) group + length is repeated as needed. Values are applied from right to left, for a + grouping of 1,00,00,000 you'd have to specify pGroups={3,2,0}. + + @param cGroupSeparator + The group separator. Ignored if pGroups is null. + + @param bEraseTrailingDecZeros + Trailing zeros in decimal places are erased. + */ +SAL_DLLPUBLIC void SAL_CALL rtl_math_doubleToString(rtl_String ** pResult, + sal_Int32 * pResultCapacity, + sal_Int32 nResultOffset, double fValue, + enum rtl_math_StringFormat eFormat, + sal_Int32 nDecPlaces, + sal_Char cDecSeparator, + sal_Int32 const * pGroups, + sal_Char cGroupSeparator, + sal_Bool bEraseTrailingDecZeros) + SAL_THROW_EXTERN_C(); + +/** Conversions analogous to sprintf() using internal rounding. + + +/-HUGE_VAL are converted to "INF" and "-INF", NAN values are + converted to "NaN". + + @param pResult + Returns the resulting Unicode string. Must itself not be null, and must + point to either null or a valid string. + + @param pResultCapacity + If null, pResult is considered to point to immutable strings, and a new + string will be allocated in pResult. + If non-null, it points to the current capacity of pResult, which is + considered to point to a string buffer (pResult must not itself be null in + this case, and must point to a string that has room for the given capacity). + The string representation of the given double value is inserted into pResult + at position nResultOffset. If pResult's current capacity is too small, a + new string buffer will be allocated in pResult as necessary, and + pResultCapacity will contain the new capacity on return. + + @param nResultOffset + If pResult is used as a string buffer (i.e., pResultCapacity is non-null), + nResultOffset specifies the insertion offset within the buffer. Ignored + otherwise. + + @param fValue + The value to convert. + + @param eFormat + The format to use, one of rtl_math_StringFormat. + + @param nDecPlaces + The number of decimals to be generated. Effectively fValue is rounded at + this position, specifying nDecPlaces <= 0 accordingly rounds the value + before the decimal point and fills with zeros. + If eFormat == rtl_math_StringFormat_Automatic and nDecPlaces == + rtl_math_DecimalPlaces_Max, the highest number of significant decimals + possible is generated. + If eFormat == rtl_math_StringFormat_G, nDecPlaces specifies the number of + significant digits instead. If nDecPlaces == + rtl_math_DecimalPlaces_DefaultSignificance, the default number (currently 6 + as implemented by most libraries) of significant digits is generated. + According to the ANSI C90 standard the E style will be used only if the + exponent resulting from the conversion is less than -4 or greater than or + equal to the precision. However, as opposed to the ANSI standard, trailing + zeros are not necessarily removed from the fractional portion of the result + unless bEraseTrailingDecZeros == true was specified. + + @param cDecSeparator + The decimal separator. + + @param pGroups + Either null (no grouping is used), or a null-terminated list of group + lengths. Each group length must be strictly positive. If the number of + digits in a conversion exceeds the specified range, the last (highest) group + length is repeated as needed. Values are applied from right to left, for a + grouping of 1,00,00,000 you'd have to specify pGroups={3,2,0}. + + @param cGroupSeparator + The group separator. Ignored if pGroups is null. + + @param bEraseTrailingDecZeros + Trailing zeros in decimal places are erased. + */ +SAL_DLLPUBLIC void SAL_CALL rtl_math_doubleToUString(rtl_uString ** pResult, + sal_Int32 * pResultCapacity, + sal_Int32 nResultOffset, double fValue, + enum rtl_math_StringFormat eFormat, + sal_Int32 nDecPlaces, + sal_Unicode cDecSeparator, + sal_Int32 const * pGroups, + sal_Unicode cGroupSeparator, + sal_Bool bEraseTrailingDecZeros) + SAL_THROW_EXTERN_C(); + +/** Conversion analogous to strtod(), convert a string representing a + decimal number into a double value. + + Leading tabs (0x09) and spaces (0x20) are eaten. Overflow returns + +/-HUGE_VAL, underflow 0. In both cases pStatus is set to + rtl_math_ConversionStatus_OutOfRange, otherwise to + rtl_math_ConversionStatus_Ok. "INF", "-INF" and "+/-1.#INF" are + recognized as +/-HUGE_VAL, pStatus is set to + rtl_math_ConversionStatus_OutOfRange. "NaN" and "+/-1.#NAN" are + recognized and the value is set to +/-NAN, pStatus is set to + rtl_math_ConversionStatus_Ok. + + @param pBegin + Points to the start of the byte string to convert. Must not be null. + + @param pEnd + Points one past the end of the byte string to convert. The condition + pEnd >= pBegin must hold. + + @param cDecSeparator + The decimal separator. + + @param cGroupSeparator + The group (aka thousands) separator. + + @param pStatus + If non-null, returns the status of the conversion. + + @param pParsedEnd + If non-null, returns one past the position of the last character parsed + away. Thus if [pBegin..pEnd) only contains the numerical string to be + parsed, *pParsedEnd == pEnd on return. If no numerical (sub-)string is + found, *pParsedEnd == pBegin on return, even if there was leading + whitespace. + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_stringToDouble( + sal_Char const * pBegin, sal_Char const * pEnd, sal_Char cDecSeparator, + sal_Char cGroupSeparator, enum rtl_math_ConversionStatus * pStatus, + sal_Char const ** pParsedEnd) SAL_THROW_EXTERN_C(); + +/** Conversion analogous to strtod(), convert a string representing a + decimal number into a double value. + + Leading tabs (U+0009) and spaces (U+0020) are eaten. Overflow returns + +/-HUGE_VAL, underflow 0. In both cases pStatus is set to + rtl_math_ConversionStatus_OutOfRange, otherwise to + rtl_math_ConversionStatus_Ok. "INF", "-INF" and "+/-1.#INF" are + recognized as +/-HUGE_VAL, pStatus is set to + rtl_math_ConversionStatus_OutOfRange. "NaN" and "+/-1.#NAN" are + recognized and the value is set to +/-NAN, pStatus is set to + rtl_math_ConversionStatus_Ok. + + @param pBegin + Points to the start of the Unicode string to convert. Must not be null. + + @param pEnd + Points one past the end of the Unicode string to convert. The condition + pEnd >= pBegin must hold. + + @param cDecSeparator + The decimal separator. + + @param cGroupSeparator + The group (aka thousands) separator. + + @param pStatus + If non-null, returns the status of the conversion. + + @param pParsedEnd + If non-null, returns one past the position of the last character parsed + away. Thus if [pBegin..pEnd) only contains the numerical string to be + parsed, *pParsedEnd == pEnd on return. If no numerical (sub-)string is + found, *pParsedEnd == pBegin on return, even if there was leading + whitespace. + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_uStringToDouble( + sal_Unicode const * pBegin, sal_Unicode const * pEnd, + sal_Unicode cDecSeparator, sal_Unicode cGroupSeparator, + enum rtl_math_ConversionStatus * pStatus, sal_Unicode const ** pParsedEnd) + SAL_THROW_EXTERN_C(); + +/** Rounds a double value. + + @param fValue + Specifies the value to be rounded. + + @param nDecPlaces + Specifies the decimal place where rounding occurs. Must be in the range + -20 to +20, inclusive. Negative if rounding occurs before the decimal + point. + + @param eMode + Specifies the rounding mode. + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_round(double fValue, int nDecPlaces, + enum rtl_math_RoundingMode eMode) + SAL_THROW_EXTERN_C(); + +/** Scales fVal to a power of 10 without calling pow() or div() for nExp values + between -16 and +16, providing a faster method. + + @param fValue + The value to be raised. + + @param nExp + The exponent. + + @return + fVal * pow(10.0, nExp) + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_pow10Exp(double fValue, int nExp) SAL_THROW_EXTERN_C(); + +/** Rounds value to 15 significant decimal digits. + + @param fValue + The value to be rounded. + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_approxValue(double fValue) SAL_THROW_EXTERN_C(); + +/** Returns more accurate e^x-1 for x near 0 than calculating directly. + + expm1 is part of the C99 standard, but not provided by some compilers. + + @param fValue + The value x in the term e^x-1. + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_expm1(double fValue) SAL_THROW_EXTERN_C(); + +/** Returns more accurate log(1+x) for x near 0 than calculating directly. + + log1p is part of the C99 standard, but not provided by some compilers. + + @param fValue + The value x in the term log(1+x). + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_log1p(double fValue) SAL_THROW_EXTERN_C(); + +/** Returns more accurate atanh(x) for x near 0 than calculating + 0.5*log((1+x)/(1-x)). + + atanh is part of the C99 standard, but not provided by some compilers. + + @param fValue + The value x in the term atanh(x). + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_atanh(double fValue) SAL_THROW_EXTERN_C(); + +/** Returns values of the Errorfunction erf. + + erf is part of the C99 standard, but not provided by some compilers. + + @param fValue + The value x in the term erf(x). + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_erf(double fValue) SAL_THROW_EXTERN_C(); + +/** Returns values of the complement Errorfunction erfc. + + erfc is part of the C99 standard, but not provided by some compilers. + + @param fValue + The value x in the term erfc(x). + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_erfc(double fValue) SAL_THROW_EXTERN_C(); + +/** Returns values of the inverse hyperbolic sine. + + asinh is part of the C99 standard, but not provided by some compilers. + + @param fValue + The value x in the term asinh(x). + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_asinh(double fValue) SAL_THROW_EXTERN_C(); + +/** Returns values of the inverse hyperbolic cosine. + + acosh is part of the C99 standard, but not provided by some compilers. + + @param fValue + The value x in the term acosh(x). + */ +SAL_DLLPUBLIC double SAL_CALL rtl_math_acosh(double fValue) SAL_THROW_EXTERN_C(); + +#if defined __cplusplus +} +#endif /* __cplusplus */ + +#endif /* INCLUDED_RTL_MATH_H */ + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |