lemon/math.h
author Alpar Juttner <alpar@cs.elte.hu>
Mon, 23 Feb 2009 11:48:47 +0000
changeset 525 635a8375227d
parent 470 81627fa1b007
child 877 141f9c0db4a3
permissions -rw-r--r--
dimacs.h reads MAT files to both dir and undir graphs (#231)
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/* -*- mode: C++; indent-tabs-mode: nil; -*-
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 *
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 * This file is a part of LEMON, a generic C++ optimization library.
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 *
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 * Copyright (C) 2003-2009
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 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
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 * (Egervary Research Group on Combinatorial Optimization, EGRES).
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 *
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 * Permission to use, modify and distribute this software is granted
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 * provided that this copyright notice appears in all copies. For
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 * precise terms see the accompanying LICENSE file.
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 *
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 * This software is provided "AS IS" with no warranty of any kind,
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 * express or implied, and with no claim as to its suitability for any
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 * purpose.
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 *
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 */
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#ifndef LEMON_MATH_H
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#define LEMON_MATH_H
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///\ingroup misc
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///\file
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///\brief Some extensions to the standard \c cmath library.
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///
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///Some extensions to the standard \c cmath library.
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///
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///This file includes the standard math library (cmath).
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#include<cmath>
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namespace lemon {
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  /// \addtogroup misc
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  /// @{
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  /// The Euler constant
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  const long double E       = 2.7182818284590452353602874713526625L;
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  /// log_2(e)
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  const long double LOG2E   = 1.4426950408889634073599246810018921L;
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  /// log_10(e)
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  const long double LOG10E  = 0.4342944819032518276511289189166051L;
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  /// ln(2)
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  const long double LN2     = 0.6931471805599453094172321214581766L;
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  /// ln(10)
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  const long double LN10    = 2.3025850929940456840179914546843642L;
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  /// pi
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  const long double PI      = 3.1415926535897932384626433832795029L;
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  /// pi/2
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  const long double PI_2    = 1.5707963267948966192313216916397514L;
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  /// pi/4
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  const long double PI_4    = 0.7853981633974483096156608458198757L;
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  /// sqrt(2)
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  const long double SQRT2   = 1.4142135623730950488016887242096981L;
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  /// 1/sqrt(2)
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  const long double SQRT1_2 = 0.7071067811865475244008443621048490L;
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  ///Check whether the parameter is NaN or not
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  ///This function checks whether the parameter is NaN or not.
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  ///Is should be equivalent with std::isnan(), but it is not
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  ///provided by all compilers.
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  inline bool isNaN(double v)
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    {
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      return v!=v;
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    }
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  /// @}
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} //namespace lemon
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#endif //LEMON_TOLERANCE_H