magn.py

import time
import math
import serial
while 1:
	ser1=serial.Serial('/dev/ttyACM0',9600)
	c2=0
	magvalues=ser1.readline()
	
	#print magvalues

	ser1.flushInput()
	c=-1;
	a=[0,0,0]
	for j in range(0,3):
	    for i in range (c+1,len(magvalues)):
	        if magvalues[i]==' ':	
	            c2=i
	            break
	    #print magvalues[c+1:c2]
	    a[j]=float(magvalues[c+1:c2])
	    c=c2
	
	PI = 3.1415 
	Xm = 2*a[0]*0.00092
	Ym = 2*a[1]*0.00092
	Zm = 2*a[2]*0.00092
	  
	heading=math.atan2(Ym,Xm)
	 
	declination = 0.021 
	heading += declination
	  
	if heading <0:
		heading += 2*PI

	if heading > 2*PI:
		heading -= 2*PI

	headingDegrees = heading * 180/PI 
	headingFiltered =0
	headingFiltered = headingFiltered*0.85 + headingDegrees*0.15

	print headingFiltered