publisher and subscriber in the same node

edit

Hello, i have a subscriber that reads the values of a flex sensor that rosserial_arduino is reading, and have another file with a publisher that writes values in a topic of the shadow hand i need to send the flex sensor values to shadow hand, the question is, can i create only one .cpp file with the subscriber and the publisher there?

already i have this two files:

Subscriber:

#include <ros/ros.h>
#include <std_msgs/Float32.h>

void indiceCallback(const std_msgs::Float32::ConstPtr& msg)
{
  ROS_INFO("Valor indice: [%f]", msg->data);
}


int main(int argc, char **argv)
{
  ros::init(argc, argv, "indice");
  ros::NodeHandle n;
  ros::Subscriber sub = n.subscribe("indice", 500, indiceCallback);
  ros::spin();

  return 0;
}

Publisher file:

#include "ros/ros.h"
#include "std_msgs/Float64.h"

#include <sstream>

int main(int argc, char **argv)
{
  ros::init(argc, argv, "prueba");
  ros::NodeHandle n;
  ros::Publisher pub = n.advertise<std_msgs::Float64>("/sh_ffj3_mixed_position_velocity_controller/command", 1000);
  ros::Rate loop_rate(10);


  int count = 0;
  while (ros::ok())
  {
    std_msgs::Float64 msg;
    msg.data = 1.5;
    ROS_INFO("%f", msg.data);
    pub.publish(msg);
    ros::spinOnce();
    loop_rate.sleep();
    ++count;
  }


  return 0;
}

As you can see the publisher file publish the data value, but there this value i change manually, i need to put there the value that i have reading in the subscriber.

Thank you a lot people!!

I already do this:

#include "ros/ros.h"
#include "std_msgs/Float64.h"
#include "std_msgs/Float32.h"

#include <sstream>

void indiceCallback(const std_msgs::Float64::ConstPtr& msg)
{
  ROS_INFO("Valor indice: [%f]", msg->data);
}

int main(int argc, char **argv)
{

  ros::init(argc, argv, "indice");
  ros::NodeHandle n;
  ros::Subscriber sub = n.subscribe("indice", 500, indiceCallback);
  ros::spin();


  ros::init(argc, argv, "prueba");
  //ros::NodeHandle n;
  ros::Publisher pub = n.advertise<std_msgs::Float64>("/sh_ffj3_mixed_position_velocity_controller/command", 500);
  ros::Rate loop_rate(10);


  int count = 0;
  while (ros::ok())
  {
    std_msgs::Float64 msg;
    //msg.data
    ROS_INFO("%f", msg.data);
    pub.publish(msg);
    ros::spinOnce();
    loop_rate.sleep();
    ++count;
  }


  return 0;
}

When i run everything the subscriber shows to me what is listening, now i need to deliver this vlues to the publisher because i need to send this values to other topic. and if i do

rostopic echo /sh_ffj3_mixed_position_velocity_controller/command

it shoot me:

WARNING: no messages received and simulated time is active.
Is /clock being published?

Any Idea??

///////////////////////////////////Edit

#include "ros/ros.h"
#include "std_msgs/Float64.h"

#include <sstream>

void indiceCallback(const std_msgs::Float64::ConstPtr& msg)
{
  ROS_INFO("Valor indice: [%f]", msg->data);
}

int main(int argc, char **argv)
{

  ros::init(argc, argv, "indice");
  ros::NodeHandle n;
  ros::Subscriber sub = n.subscribe("indice", 500, indiceCallback);
  ros::spin();


  ros::Publisher pub = n.advertise<std_msgs::Float64>("/sh_ffj3_mixed_position_velocity_controller/command", 500);
  ros::Rate loop_rate(10);
  ros::spinOnce();

  int count = 0;
  while (ros::ok())
  {
    std_msgs::Float64 msg;
    //msg.data
    ROS_INFO("%f", msg.data);
    pub.publish(msg);
    ros::spinOnce();
    loop_rate.sleep();
    ++count;
  }


  return 0;
}

EDIT///////////////////////////////////////////////////////////

the code is like that:

#include "ros/ros.h"
#include "std_msgs/Float64.h"
#include <sstream>

void indiceCallback(const std_msgs::Float64::ConstPtr& msg)
{
  ROS_INFO("Valor indice: [%f]", msg->data);
}

int main ...