math_util.cpp

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#include <swri_math_util/math_util.h>

#include <cmath>

namespace swri_math_util
{
  double Round(double value)
  {
    return (value > 0.0) ? std::floor(value + 0.5) : std::ceil(value - 0.5);
  }

  double ToNearest(double value, double multiple)
  {
    if (multiple == 0)
    {
      return 0;
    }

    return Round(value / multiple) * multiple;
  }

  double UpToNearest(double value, double multiple)
  {
    if (multiple == 0)
    {
      return 0;
    }

    return std::ceil(value / multiple) * multiple;
  }

  bool IsNear(double v1, double v2, double epsilon)
  {
    return std::fabs(v1 - v2) <= epsilon;
  }

  double unWrapAngle(double static_angle,
                     double variable_angle,
                     double threshold)
  {
    if (std::abs(static_angle - variable_angle) > threshold)
    {
      if (variable_angle < static_angle)
      {
        variable_angle += swri_math_util::_2pi;
      }
      else
      {
        variable_angle -= swri_math_util::_2pi;
      }
    }
    return variable_angle;
  }
}