mfexp.cpp

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/*
\file Robust exponential functions for variable scalar objects.

Author: David Fournier
Copyright (c) 2008-2015 Regents of the University of California
*/
#include <fvar.hpp>

dvariable mfexp(const prevariable& x, double b)
{
  if (x > b)
  {
    return exp(b)*(1.+2.*(x-b))/(1.+x-b);
  }
  else if (x < -b)
  {
    return exp(-b)*(1.-x-b)/(1.+2.*(-x-b));
  }
  return exp(x);
}
dvariable mfexp(const prevariable& x)
{
  double b = 60;
  return mfexp(x, b);
}