fix new cppcheck warnings

Signed-off-by: Ryuta Kambe <ryuta.kambe@tier4.jp>

Author: veqcc

perception/autoware_map_based_prediction/src/map_based_prediction_node.cpp

@@ -1776,7 +1776,7 @@ std::vector<PredictedRefPath> MapBasedPredictionNode::getPredictedReferencePath(
   auto get_search_distance_with_decaying_acc = [&]() -> double {
     const double acceleration_distance =
       obj_acc * (1.0 / lambda) * t_h +
-      obj_acc * (1.0 / std::pow(lambda, 2)) * (std::exp(-lambda * t_h) - 1);
+      obj_acc * (1.0 / std::pow(lambda, 2)) * std::expm1(-lambda * t_h);
     double search_dist = acceleration_distance + obj_vel * t_h;
     return search_dist;
   };
@@ -1794,7 +1794,7 @@ std::vector<PredictedRefPath> MapBasedPredictionNode::getPredictedReferencePath(
     const double search_dist =
       // Distance covered while accelerating
       obj_acc * (1.0 / lambda) * t_f +
-      obj_acc * (1.0 / std::pow(lambda, 2)) * (std::exp(-lambda * t_f) - 1) + obj_vel * t_f +
+      obj_acc * (1.0 / std::pow(lambda, 2)) * std::expm1(-lambda * t_f) + obj_vel * t_f +
       // Distance covered at constant speed
       final_speed * (t_h - t_f);
     return search_dist;

perception/autoware_map_based_prediction/src/path_generator.cpp

@@ -447,12 +447,12 @@ FrenetPoint PathGenerator::getFrenetPoint(
       // e^(-lambda t_stop) = 1 - (-Vo* lambda)/acc
       // t_stop = (-1/lambda)*ln(1 - (-Vo* lambda)/acc)
       // t_stop = (-1/lambda)*ln(1 + (Vo* lambda)/acc)
-      auto t_stop = (-1.0 / lambda) * std::log(1 + (v * lambda / a));
+      auto t_stop = (-1.0 / lambda) * std::log1p(v * lambda / a);
 
       // Calculate the distance traveled until stopping
       auto distance_to_reach_zero_speed =
         v * t_stop + a * t_stop * (1.0 / lambda) +
-        a * (1.0 / std::pow(lambda, 2)) * (std::exp(-lambda * t_h) - 1);
+        a * (1.0 / std::pow(lambda, 2)) * std::expm1(-lambda * t_h);
       // Output an equivalent constant speed
       return distance_to_reach_zero_speed / t_h;
     }
@@ -463,7 +463,7 @@ FrenetPoint PathGenerator::getFrenetPoint(
     const bool object_has_surpassed_limit_already = v > speed_limit;
     if (terminal_velocity < speed_limit || object_has_surpassed_limit_already)
       return v + a * (1.0 / lambda) +
-             (a / (t_h * std::pow(lambda, 2))) * (std::exp(-lambda * t_h) - 1);
+             (a / (t_h * std::pow(lambda, 2))) * std::expm1(-lambda * t_h);
 
     // It is assumed the vehicle accelerates until final_speed is reached and
     // then continues at constant speed for the rest of the time horizon
@@ -473,7 +473,7 @@ FrenetPoint PathGenerator::getFrenetPoint(
     const double t_f = (-1.0 / lambda) * std::log(1 - ((speed_limit - v) * lambda) / a);
     const double distance_covered =
       // Distance covered while accelerating
-      a * (1.0 / lambda) * t_f + a * (1.0 / std::pow(lambda, 2)) * (std::exp(-lambda * t_f) - 1) +
+      a * (1.0 / lambda) * t_f + a * (1.0 / std::pow(lambda, 2)) * std::expm1(-lambda * t_f) +
       v * t_f +
       // Distance covered at constant speed for the rest of the horizon time
       speed_limit * (t_h - t_f);