#!/usr/bin/env python
import rospy
import struct
import os
from dodo_detector_ros.msg import UserData
def loop():
rospy.init_node('wifi_signal_pub', anonymous=True)
pub = rospy.Publisher('wifi_signal', UserData, queue_size=10)
rate = rospy.Rate(0.5) # 0.5hz
while not rospy.is_shutdown():
myCmd = os.popen('nmcli dev wifi | grep "^*"').read()
cmdList = myCmd.split()
if len(cmdList) > 6:
quality = float(cmdList[6])
msg = UserData()
# To make it compatible with c++ sub example, use dBm
dBm = quality/2-100
rospy.loginfo("Network \"%s\": Quality=%d, %f dBm", cmdList[1], quality, dBm)
# Create user data [level, stamp].
# Any format is accepted.
# However, if CV_8UC1 format is used, make sure rows > 1 as
# rtabmap will think it is already compressed.
msg.rows = 1
msg.cols = 2
msg.type = 6 # Use OpenCV type (here 6=CV_64FC1): http://ninghang.blogspot.com/2012/11/list-of-mat-type-in-opencv.html
# We should set stamp in data to be able to
# retrieve it from the saved user data as we need
# to get precise position in the graph afterward.
msg.data = struct.pack(b'dd', dBm, rospy.get_time())
pub.publish(msg)
else:
rospy.logerr("Cannot get info from wireless!")
rate.sleep()
if __name__ == '__main__':
try:
loop()
except rospy.ROSInterruptException:
pass
The output is:
Traceback (most recent call last):
File "/home/redhwan/catkin_ws/src/wifi_signal_pub.py", line 44, in <module>
loop()
File "/home/redhwan/catkin_ws/src/wifi_signal_pub.py", line 17, in loop
quality = float(cmdList[6])
ValueError: could not convert string to float: BARS
When I print (cmdList) :
I see this output but I don't know what the quality index is in this list?
I am still working on Ubuntu 16.04.
I am running this code:
The output is:
When I
print (cmdList)
:I see this output but I don't know what the quality index is in this list?
['*', 'SSID', 'MODE', 'CHAN', 'RATE', 'SIGNAL', 'BARS', 'SECURITY', '*', 'Hlab_linksys', 'Infra', '157', '54', 'Mbit/s', '100', '\xe2\x96\x82\xe2\x96\x84\xe2\x96\x86\xe2\x96\x88', 'WPA2']
Please, your help.
Thanks.