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Diffstat (limited to 'kcalc/knumber/knumber.h')
| -rw-r--r-- | kcalc/knumber/knumber.h | 289 |
1 files changed, 289 insertions, 0 deletions
diff --git a/kcalc/knumber/knumber.h b/kcalc/knumber/knumber.h new file mode 100644 index 0000000..489a579 --- /dev/null +++ b/kcalc/knumber/knumber.h @@ -0,0 +1,289 @@ +// -*- c-basic-offset: 2 -*- +/* This file is part of the KDE libraries + Copyright (C) 2005 Klaus Niederkrueger <kniederk@math.uni-koeln.de> + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public License + along with this library; see the file COPYING.LIB. If not, write to + the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + Boston, MA 02110-1301, USA. +*/ +#ifndef _KNUMBER_H +#define _KNUMBER_H + +#include <kdelibs_export.h> + +#include "knumber_priv.h" + +class QString; + +/** + * + * @short Class that provides arbitrary precision numbers + * + * KNumber provides access to arbitrary precision numbers from within + * KDE. + * + * KNumber is based on the GMP (GNU Multiprecision) library and + * provides transparent support to integer, fractional and floating + * point number. It contains rudimentary error handling, and also + * includes methods for converting the numbers to QStrings for + * output, and to read QStrings to obtain a KNumber. + * + * The different types of numbers that can be represented by objects + * of this class will be described below: + * + * @li @p NumType::SpecialType - This type represents an error that + * has occurred, e.g. trying to divide 1 by 0 gives an object that + * represents infinity. + * + * @li @p NumType::IntegerType - The number is an integer. It can be + * arbitrarily large (restricted by the memory of the system). + * + * @li @p NumType::FractionType - A fraction is a number of the form + * denominator divided by nominator, where both denominator and + * nominator are integers of arbitrary size. + * + * @li @p NumType::FloatType - The number is of floating point + * type. These numbers are usually rounded, so that they do not + * represent precise values. + * + * + * @author Klaus Niederkrueger <kniederk@math.uni-koeln.de> + */ +class KDE_EXPORT KNumber +{ + public: + static KNumber const Zero; + static KNumber const One; + static KNumber const MinusOne; + static KNumber const Pi; + static KNumber const Euler; + static KNumber const NotDefined; + + /** + * KNumber tries to provide transparent access to the following type + * of numbers: + * + * @li @p NumType::SpecialType - Some type of error has occurred, + * further inspection with @p KNumber::ErrorType + * + * @li @p NumType::IntegerType - the number is an integer + * + * @li @p NumType::FractionType - the number is a fraction + * + * @li @p NumType::FloatType - the number is of floating point type + * + */ + enum NumType {SpecialType, IntegerType, FractionType, FloatType}; + + /** + * A KNumber that represents an error, i.e. that is of type @p + * NumType::SpecialType can further distinguished: + * + * @li @p ErrorType::UndefinedNumber - This is e.g. the result of + * taking the square root of a negative number or computing + * \f$ \infty - \infty \f$. + * + * @li @p ErrorType::Infinity - Such a number can be e.g. obtained + * by dividing 1 by 0. Some further calculations are still allowed, + * e.g. \f$ \infty + 5 \f$ still gives \f$\infty\f$. + * + * @li @p ErrorType::MinusInfinity - MinusInfinity behaves similarly + * to infinity above. It can be obtained by changing the sign of + * infinity. + * + */ + enum ErrorType {UndefinedNumber, Infinity, MinusInfinity}; + + KNumber(signed int num = 0); + KNumber(unsigned int num); + KNumber(signed long int num); + KNumber(unsigned long int num); + KNumber(unsigned long long int num); + + KNumber(double num); + + KNumber(KNumber const & num); + + KNumber(QString const & num); + + ~KNumber() + { + delete _num; + } + + KNumber const & operator=(KNumber const & num); + + /** + * Returns the type of the number, as explained in @p KNumber::NumType. + */ + NumType type(void) const; + + /** + * Set whether the output of numbers (with KNumber::toQString) + * should happen as floating point numbers or not. This method has + * in fact only an effect on numbers of type @p + * NumType::FractionType, which can be either displayed as fractions + * or in decimal notation. + * + * The default behavior is not to display fractions in floating + * point notation. + */ + static void setDefaultFloatOutput(bool flag); + + /** + * Set whether a number constructed from a QString should be + * initialized as a fraction or as a float, e.g. "1.01" would be + * treated as 101/100, if this flag is set to true. + * + * The default setting is false. + */ + static void setDefaultFractionalInput(bool flag); + + /** + * Set the default precision to be *at least* @p prec (decimal) + * digits. All subsequent initialized floats will use at least this + * precision, but previously initialized variables are unaffected. + */ + static void setDefaultFloatPrecision(unsigned int prec); + + /** + * What a terrible method name!! When displaying a fraction, the + * default mode gives @p "nomin/denom". With this method one can + * choose to display a fraction as @p "integer nomin/denom". + * + * Examples: Default representation mode is 47/17, but if @p flag is + * @p true, then the result is 2 13/17. + */ + static void setSplitoffIntegerForFractionOutput(bool flag); + + /** + * Return a QString representing the KNumber. + * + * @param width This number specifies the maximal length of the + * output, before the method switches to exponential notation and + * does rounding. For negative numbers, this option is ignored. + * + * @param prec This parameter controls the number of digits + * following the decimal point. For negative numbers, this option + * is ignored. + * + */ + QString const toQString(int width = -1, int prec = -1) const; + + /** + * Compute the absolute value, i.e. @p x.abs() returns the value + * + * \f[ \left\{\begin{array}{cl} x, & x \ge 0 \\ -x, & x < + * 0\end{array}\right.\f] + * This method works for \f$ x = \infty \f$ and \f$ x = -\infty \f$. + */ + KNumber const abs(void) const; + + /** + * Compute the square root. If \f$ x < 0 \f$ (including \f$ + * x=-\infty \f$), then @p x.sqrt() returns @p + * ErrorType::UndefinedNumber. + * + * If @p x is an integer or a fraction, then @p x.sqrt() tries to + * compute the exact square root. If the square root is not a + * fraction, then a float with the default precision is returned. + * + * This method works for \f$ x = \infty \f$ giving \f$ \infty \f$. + */ + KNumber const sqrt(void) const; + + /** + * Compute the cube root. + * + * If @p x is an integer or a fraction, then @p x.cbrt() tries to + * compute the exact cube root. If the cube root is not a fraction, + * then a float is returned, but + * + * WARNING: A float cube root is computed as a standard @p double + * that is later transformed back into a @p KNumber. + * + * This method works for \f$ x = \infty \f$ giving \f$ \infty \f$, + * and for \f$ x = -\infty \f$ giving \f$ -\infty \f$. + */ + KNumber const cbrt(void) const; + + /** + * Truncates a @p KNumber to its integer type returning a number of + * type @p NumType::IntegerType. + * + * If \f$ x = \pm\infty \f$, integerPart leaves the value unchanged, + * i.e. it returns \f$ \pm\infty \f$. + */ + KNumber const integerPart(void) const; + + KNumber const power(KNumber const &exp) const; + + KNumber const operator+(KNumber const & arg2) const; + KNumber const operator -(void) const; + KNumber const operator-(KNumber const & arg2) const; + KNumber const operator*(KNumber const & arg2) const; + KNumber const operator/(KNumber const & arg2) const; + KNumber const operator%(KNumber const & arg2) const; + + KNumber const operator&(KNumber const & arg2) const; + KNumber const operator|(KNumber const & arg2) const; + KNumber const operator<<(KNumber const & arg2) const; + KNumber const operator>>(KNumber const & arg2) const; + + operator bool(void) const; + operator signed long int(void) const; + operator unsigned long int(void) const; + operator unsigned long long int(void) const; + operator double(void) const; + + bool const operator==(KNumber const & arg2) const + { return (compare(arg2) == 0); } + + bool const operator!=(KNumber const & arg2) const + { return (compare(arg2) != 0); } + + bool const operator>(KNumber const & arg2) const + { return (compare(arg2) > 0); } + + bool const operator<(KNumber const & arg2) const + { return (compare(arg2) < 0); } + + bool const operator>=(KNumber const & arg2) const + { return (compare(arg2) >= 0); } + + bool const operator<=(KNumber const & arg2) const + { return (compare(arg2) <= 0); } + + KNumber & operator +=(KNumber const &arg); + KNumber & operator -=(KNumber const &arg); + + + //KNumber const toFloat(void) const; + + + + + private: + void simplifyRational(void); + int const compare(KNumber const & arg2) const; + + _knumber *_num; + static bool _float_output; + static bool _fraction_input; + static bool _splitoffinteger_output; +}; + + + +#endif // _KNUMBER_H |