title: Use data from multiple topics in ROS - Python
body: <p>I'm able to display data from two topics but I can't do use and compute data in real time from these two topics in ROS (written in Python code). </p>
  
  <p>Have you got any idea to stock this data and compute in real time ? </p>
  
  <p>Thanks ;)</p>
  
  <pre><code>#!/usr/bin/env python
  
  import rospy
  import string
  from std_msgs.msg import String 
  from std_msgs.msg import Float64MultiArray
  from std_msgs.msg import Float64
  import numpy as np
  
  
  class ListenerVilma:
  
      def __init__(self):
          self.orientation = rospy.Subscriber('/orientation', Float64MultiArray , self.orientation_callback)
          self.velocidade = rospy.Subscriber('/velocidade', Float64MultiArray, self.velocidade_callback)
  
      def orientation_callback(self, orientation):
          print orientation
  
      def velocidade_callback(self, velocidade):
          print velocidade
  
  
  if __name__ == '__main__':
     rospy.init_node('listener', anonymous=True)
     myVilma = ListenerVilma()
     rospy.spin()
  </code></pre>