从 gps 检索错误数据

Question

我一直在尝试实现一个程序来打印出我的 GPS 坐标。但是，我收到的数据完全没有意义。

我的 class 个文件：

class GpsHandler
{
public:
    GpsHandler(const std::string& gpsDaemonIpAddress, uint16_t updateRate);

    ~GpsHandler();

    void initialize();
    void printoutData();
private:
    std::shared_ptr<gpsmm> m_gpsRec;
    struct gps_data_t*     m_currentGpsData;
};


GpsHandler::GpsHandler(const std::string& gpsDaemonIpAddress, uint16_t updateRate)
m_gpsRec(std::make_shared<gpsmm>(gpsDaemonIpAddress.c_str(), DEFAULT_GPSD_PORT)),
s_updaterate(updateRate)
{}

void GpsHandler::initialize()

{
    if (m_gpsRec->stream(WATCH_ENABLE | WATCH_JSON) == nullptr) {
        LOG4CPLUS_ERROR(m_logger, "No GPSD daemon running");
        throw std::runtime_error("No GPSD daemon running");
    }

    if (!m_gpsRec->is_open()) {
        LOG4CPLUS_ERROR(m_logger, "Open connection to gps daemon failed");
        throw std::runtime_error("Open connection to gps daemon failed");
    }
}

void GpsHandler::printoutData()
{
    if (!m_gpsRec->waiting(50000)) {
        LOG4CPLUS_WARN(m_logger, "Wait for gps daemon failed");
    }

    if ((m_currentGpsData = m_gpsRec->read()) != nullptr) {
        if (m_currentGpsData->set & ONLINE_SET) {
            LOG4CPLUS_INFO_FMT(m_logger, "Online: %lf", m_currentGpsData->online);
        }

        if (m_currentGpsData->set & TIME_SET)
            LOG4CPLUS_INFO_FMT(m_logger, "Time: %lf", m_currentGpsData->fix.time);

        if (m_currentGpsData->set & LATLON_SET)
            LOG4CPLUS_INFO_FMT(m_logger, "LATLON: lat/lon: %lf %lf", m_currentGpsData->fix.latitude, m_currentGpsData->fix.longitude);

        if (m_currentGpsData->set & ALTITUDE_SET)
            LOG4CPLUS_INFO_FMT(m_logger, "ALTITUDE: altitude: %lf  U: climb: %lf\n", m_currentGpsData->fix.altitude, m_currentGpsData->fix.climb);

        if (m_currentGpsData->set & SPEED_SET)
            LOG4CPLUS_INFO_FMT(m_logger, "SPEED: %lf\n", m_currentGpsData->fix.speed);

        if (m_currentGpsData->set & TRACK_SET)
            LOG4CPLUS_INFO_FMT(m_logger, "TRACK: track: %lf\n", m_currentGpsData->fix.track);

        if (m_currentGpsData->set & STATUS_SET)
            LOG4CPLUS_INFO_FMT(m_logger, "STATUS: status: %d\n", m_currentGpsData->status);

        if (m_currentGpsData->set & MODE_SET)
            LOG4CPLUS_INFO_FMT(m_logger, "MODE: mode: %d\n", m_currentGpsData->fix.mode);

    } else {
        LOG4CPLUS_INFO(m_logger, "error reading ");
    }
}

我的主程序：

int main(int argc, char* argv[])
{
    try {
        QCoreApplication app(argc, argv);

        int sleepStep = 500000;
        std::shared_ptr<GpsHandler> m_gpsHandler;
        m_gpsHandler = std::make_shared<GpsHandler>("local  host ip address", 2); 
                      
        m_gpsHandler->initialize();

        while (!m_signalcaught) {
            m_gpsHandler->printoutData();
             usleep(sleepStep);
}
 } catch (std::exception& e) {
    }
    return 0;
}

这是我得到的示例输出：

其中一个观察是解析的经度值实际上是海拔值（427m）解析的高度值以荒谬的方式波动。解析的纬度值实际上是我的经度值。已解析的时间戳未更改且不正确。

谢谢

Answer 1

是库版本不同的问题。 gps_data 结构的一些变化是在较新版本的 libgpsmm (3.22) 中引入的，而我使用的是旧版本。因此，我得到了错误的数据。

从 gps 检索错误数据

Retrieving the wrong data from gps

c++

gps

gpsd