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//-----------------------------------------------------------------------------
/** @file libboardgame_base/MathUtil.h
@author Markus Enzenberger
@copyright GNU General Public License version 3 or later */
//-----------------------------------------------------------------------------
#ifndef LIBBOARDGAME_BASE_MATH_UTIL_H
#define LIBBOARDGAME_BASE_MATH_UTIL_H
namespace libboardgame_base {
//-----------------------------------------------------------------------------
/** Fast approximation of exp(x).
The error is less than 15% for abs(x) \< 10 */
template<typename T>
inline T fast_exp(T x)
{
x = static_cast<T>(1) + x / static_cast<T>(256);
x *= x;
x *= x;
x *= x;
x *= x;
x *= x;
x *= x;
x *= x;
x *= x;
return x;
}
/** Modulus operation with always positive result. */
inline int mod(int a, int b)
{
return ((a % b) + b) % b;
}
//-----------------------------------------------------------------------------
} // namespace libboardgame_base
#endif // LIBBOARDGAME_BASE_MATH_UTIL_H
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