math_utils_tpl.h

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 *       - Christophe GONZALES(_at_AMU)                                     *
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 *       - Pierre-Henri WUILLEMIN(_at_LIP6)                                 *
 *       - Christophe GONZALES(_at_AMU)                                     *
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#pragma once
 
#include <agrum/base/core/math/math_utils.h>
 
namespace gum {
  template < typename T >
  bool isCloseToZero(T x, T tol) {
    return std::abs(x) <= tol;
  }
 
  template < typename T >
  bool isCloseToOne(T x, T tol) {
    return std::abs(x - T(1)) <= tol;
  }
 
  template < typename T >
  bool isfinite(T arg) {
    if constexpr (std::numeric_limits< T >::has_infinity) {
      if constexpr (std::numeric_limits< T >::is_signed) {
        return arg == arg && arg != std::numeric_limits< T >::infinity()
            && arg != -std::numeric_limits< T >::infinity();   // neither Nan, infty nor -infty
      } else {
        return arg == arg
            && arg != std::numeric_limits< T >::infinity();    // neither Nan nor inftty
      }
    } else {
      return arg == arg;                                       // not Nan
    }
  }
}   // namespace gum