I'm on ROS melodic and ubuntu 18.04.

I use a ublox gps module and I try to get the longitude and latitude with a precision of e-7.

I manage to display the coordinates on the topic with rostopic echo /ubloxgps/fix from https://github.com/ros-agriculture/ubloxf9p and I'm getting good latitude and longitude with accuracy e-7.

But when I create a subscriber (see below) to get these values , the accuracy of the latitude changes to e-4 but the longitude remains at e-7.

Do you know why? I don't know where to look to change the accuracy.

The code suscriber (c++):

#include <iostream>
#include <ros/ros.h>
#include <sensor_msgs/NavSatFix.h>
#include <sensor_msgs/NavSatStatus.h>

void callback(const sensor_msgs::NavSatFixConstPtr &fix) {

  if (fix->status.status == sensor_msgs::NavSatStatus::STATUS_NO_FIX) {

    std::cout << "Unable to get a fix on the location." << std::endl;
    return;
      }

  double longitude = fix->longitude;
  double latitude = fix->latitude;

  std::cout << "Current Latitude: "  << latitude  << std::endl;
  std::cout << "Current Longitude: " << longitude << std::endl;

}
int main(int argc, char **argv) {
  ros::init(argc, argv, "suscriber_ublox");
  ros::NodeHandle nh;

  ros::Subscriber gps_sub = nh.subscribe("/ublox_gps/fix", 10, callback);

  ros::spin();
  return 0;
}