1

src/cpp_pubsub/src/chatter_publisher.cpp

@@ -18,22 +18,22 @@ ChatterPublisher::ChatterPublisher(const rclcpp::NodeOptions & options)
 : rclcpp::Node("chatter_publisher", options), publish_count_(0)
 {
   // 1) 声明参数(类型模板版 + 描述符)
-  this->declare_parameter<int>(
-    "publish_rate_hz", 2,
+  this->declare_parameter<double>(
+    "publish_rate_hz", 2.0,
     rcl_interfaces::msg::ParameterDescriptor().set__description("发布频率 (Hz)"));
   this->declare_parameter<std::string>(
     "topic_name", "chatter",
     rcl_interfaces::msg::ParameterDescriptor().set__description("发布话题名"));
 
   // 2) 读参数
-  const int publish_rate_hz = this->get_parameter("publish_rate_hz").as_int();
+  const double publish_rate_hz = this->get_parameter("publish_rate_hz").as_double();
   const std::string topic_name = this->get_parameter("topic_name").as_string();
 
   // 3) 构造发布者 + 定时器
   publisher_ = this->create_publisher<std_msgs::msg::String>(topic_name, 10);
 
-  const auto period = (publish_rate_hz > 0) ?
-    std::chrono::milliseconds(1000 / publish_rate_hz) :
+  const auto period = (publish_rate_hz > 0.0) ?
+    std::chrono::milliseconds(static_cast<int>(1000.0 / publish_rate_hz)) :
     std::chrono::milliseconds(1000);
 
   timer_ = this->create_wall_timer(
@@ -41,7 +41,7 @@ ChatterPublisher::ChatterPublisher(const rclcpp::NodeOptions & options)
 
   RCLCPP_INFO(
     this->get_logger(),
-    "ChatterPublisher started: rate=%d Hz, topic=\"%s\"",
+    "ChatterPublisher started: rate=%.2f Hz, topic=\"%s\"",
     publish_rate_hz, topic_name.c_str());
 }
 

src/cpp_pubsub/test/test_pub_sub.cpp

@@ -34,7 +34,7 @@ TEST_F(PubsubTest, PublisherConstructsWithDefaults)
 {
   auto node = std::make_shared<cpp_pubsub::ChatterPublisher>();
   EXPECT_EQ(node->get_name(), std::string("chatter_publisher"));
-  EXPECT_EQ(node->get_parameter("publish_rate_hz").as_int(), 2);
+  EXPECT_DOUBLE_EQ(node->get_parameter("publish_rate_hz").as_double(), 2.0);
   EXPECT_EQ(node->get_parameter("topic_name").as_string(), std::string("chatter"));
 }