Refacto, fix PR #3 , added instruments inclinometer and heading .

.gitignore

@@ -60,3 +60,4 @@ target/
 
 #Ipython Notebook
 .ipynb_checkpoints
+.idea

Adafruit_LSM303/LSM303.py

@@ -21,26 +21,25 @@
 # SOFTWARE.
 import struct
 
-
 # Minimal constants carried over from Arduino library:
 LSM303_ADDRESS_ACCEL = (0x32 >> 1)  # 0011001x
-LSM303_ADDRESS_MAG   = (0x3C >> 1)  # 0011110x
-                                         # Default    Type
-LSM303_REGISTER_ACCEL_CTRL_REG1_A = 0x20 # 00000111   rw
-LSM303_REGISTER_ACCEL_CTRL_REG4_A = 0x23 # 00000000   rw
-LSM303_REGISTER_ACCEL_OUT_X_L_A   = 0x28
-LSM303_REGISTER_MAG_CRB_REG_M     = 0x01
-LSM303_REGISTER_MAG_MR_REG_M      = 0x02
-LSM303_REGISTER_MAG_OUT_X_H_M     = 0x03
+LSM303_ADDRESS_MAG = (0x3C >> 1)  # 0011110x
+# Default    Type
+LSM303_REGISTER_ACCEL_CTRL_REG1_A = 0x20  # 00000111   rw
+LSM303_REGISTER_ACCEL_CTRL_REG4_A = 0x23  # 00000000   rw
+LSM303_REGISTER_ACCEL_OUT_X_L_A = 0x28
+LSM303_REGISTER_MAG_CRB_REG_M = 0x01
+LSM303_REGISTER_MAG_MR_REG_M = 0x02
+LSM303_REGISTER_MAG_OUT_X_H_M = 0x03
 
 # Gain settings for set_mag_gain()
-LSM303_MAGGAIN_1_3 = 0x20 # +/- 1.3
-LSM303_MAGGAIN_1_9 = 0x40 # +/- 1.9
-LSM303_MAGGAIN_2_5 = 0x60 # +/- 2.5
-LSM303_MAGGAIN_4_0 = 0x80 # +/- 4.0
-LSM303_MAGGAIN_4_7 = 0xA0 # +/- 4.7
-LSM303_MAGGAIN_5_6 = 0xC0 # +/- 5.6
-LSM303_MAGGAIN_8_1 = 0xE0 # +/- 8.1
+LSM303_MAGGAIN_1_3 = 0x20  # +/- 1.3
+LSM303_MAGGAIN_1_9 = 0x40  # +/- 1.9
+LSM303_MAGGAIN_2_5 = 0x60  # +/- 2.5
+LSM303_MAGGAIN_4_0 = 0x80  # +/- 4.0
+LSM303_MAGGAIN_4_7 = 0xA0  # +/- 4.7
+LSM303_MAGGAIN_5_6 = 0xC0  # +/- 5.6
+LSM303_MAGGAIN_8_1 = 0xE0  # +/- 8.1
 
 
 class LSM303(object):
@@ -75,17 +74,31 @@ def read(self):
         be returned with:
           ((accel X, accel Y, accel Z), (mag X, mag Y, mag Z))
         """
+        return self.read_accelerometer(), self.read_magnetometer()
+
+    def read_accelerometer(self):
+
+        """
+        :rtype: (accel X, accel Z, accel Y ) (meters per second squared)
+        """
         # Read the accelerometer as signed 16-bit little endian values.
         accel_raw = self._accel.readList(LSM303_REGISTER_ACCEL_OUT_X_L_A | 0x80, 6)
         accel = struct.unpack('<hhh', accel_raw)
         # Convert to 12-bit values by shifting unused bits.
         accel = (accel[0] >> 4, accel[1] >> 4, accel[2] >> 4)
-        # Read the magnetometer.
+        return accel
+
+    def read_magnetometer(self):
+
+        """
+        :rtype: (mag X, mag Y, mag Z) (micro-Teslas)
+        """
         mag_raw = self._mag.readList(LSM303_REGISTER_MAG_OUT_X_H_M, 6)
         mag = struct.unpack('>hhh', mag_raw)
-        return (accel, mag)
 
-    def set_mag_gain(gain=LSM303_MAGGAIN_1_3):
+        return mag
+
+    def set_mag_gain(self, gain=LSM303_MAGGAIN_1_3):
         """Set the magnetometer gain.  Gain should be one of the following
         constants:
          - LSM303_MAGGAIN_1_3 = +/- 1.3 (default)

Adafruit_LSM303/instruments.py

@@ -0,0 +1,39 @@
+from math import atan2, degrees
+
+
+class Instrument:
+    def __init__(self, lsm303_sensor):
+        """
+        :type lsm303_sensor : Adafruit_LSM303.LSM303.LSM303
+        """
+        self.lsm303_sensor = lsm303_sensor
+
+    def vector_2_degrees(self, x, y):
+        radians = atan2(y, x)
+        degrees_calc = degrees(radians)
+        if degrees_calc < 0:
+            degrees_calc = 360 + degrees_calc
+        return degrees_calc
+
+
+class Compass(Instrument):
+    def get_heading(self):
+        magnet_axis_data = self.lsm303_sensor.read_magnetometer()
+        return self.vector_2_degrees(magnet_axis_data[0], magnet_axis_data[2])
+
+
+class Inclinometer(Instrument):
+
+    def get_inclination(self):
+        return self.get_inclination_respect_x(), self.get_inclination_respect_y()
+
+    def get_inclination_respect_x(self):
+        accel_axis_data = self.get_data()
+        return self.vector_2_degrees(accel_axis_data[0], accel_axis_data[2])
+
+    def get_inclination_respect_y(self):
+        accel_axis_data = self.get_data()
+        return self.vector_2_degrees(accel_axis_data[1], accel_axis_data[2])
+
+    def get_data(self):
+        return self.lsm303_sensor.read_accelerometer()

examples/compass.py

@@ -0,0 +1,23 @@
+
+import time
+import sys
+
+import Adafruit_LSM303
+from Adafruit_LSM303.instruments import Compass
+
+lsm303 = Adafruit_LSM303.LSM303()
+
+# Setting magnetic gain. you can check it at http://www.magnetic-declination.com/
+#lsm303.set_mag_gain(Adafruit_LSM303.LSM303_MAGGAIN_4_7)
+
+compass = Compass(lsm303)
+
+print('Printing heading ..')
+
+while True:
+
+    heading = compass.get_heading()
+    data = '\rHeading (Degrees): {0} '.format(heading)
+    sys.stdout.write(data)
+    sys.stdout.flush()
+    time.sleep(0.1)

examples/inclinometer.py

@@ -0,0 +1,26 @@
+import time
+import sys
+
+import Adafruit_LSM303
+from Adafruit_LSM303.instruments import Inclinometer
+
+lsm303 = Adafruit_LSM303.LSM303()
+
+# Setting magnetic gain. you can check it at http://www.magnetic-declination.com/
+# lsm303.set_mag_gain(Adafruit_LSM303.LSM303_MAGGAIN_4_7)
+
+inclinometer = Inclinometer(lsm303)
+
+print('Printing Inclination (Degrees) based on x-y-z respective angle ...')
+
+"""
+ Information printed is adapted to positive and negative degrees per axis. From 0 to 179 and from 0 to -179
+ This means that if you are on pitch down movement you will get a negative number until 
+ you reach the noise of the sensor shooting again the sky.
+"""
+while True:
+    inclination = inclinometer.get_inclination()
+    data = '\rX : {0}   Y: {1}'.format(inclination[0], inclination[1])
+    sys.stdout.write(data)
+    sys.stdout.flush()
+    time.sleep(0.1)

examples/simple.py

@@ -0,0 +1,36 @@
+# Simple demo of of the LSM303 accelerometer & magnetometer library.
+# Will print the accelerometer & magnetometer X, Y, Z axis values every half
+# second.
+# Author: Tony DiCola
+# License: Public Domain
+
+import time
+import sys
+
+import Adafruit_LSM303
+
+lsm303 = Adafruit_LSM303.LSM303()
+
+# Setting magnetic gain. you can check it at http://www.magnetic-declination.com/
+# lsm303.set_mag_gain(Adafruit_LSM303.LSM303_MAGGAIN_4_7)
+
+# Alternatively you can specify the I2C bus with a bus parameter:
+# lsm303 = Adafruit_LSM303.LSM303(busum=2)
+
+print('Printing accelerometer & magnetometer X, Y, Z axis values, press Ctrl-C to quit...')
+while True:
+    accel = lsm303.read_accelerometer()
+    mag = lsm303.read_magnetometer()
+
+    # You also can get a accel + mag tuple with this function
+    # total_data = lsm303.read()
+
+    accel_x, accel_y, accel_z = accel
+    mag_x, mag_z, mag_y = mag
+
+    data = '\rAccel X={0}, Accel Y={1}, Accel Z={2}, Mag X={3}, Mag Y={4}, Mag Z={5}'.format(accel_x, accel_y, accel_z,
+                                                                                           mag_x, mag_y, mag_z)
+    sys.stdout.write(data)
+    sys.stdout.flush()
+
+    time.sleep(0.1)

test/test_instrument.py

@@ -0,0 +1,28 @@
+from unittest import TestCase
+
+from ddt import ddt, data, unpack
+from mock import MagicMock
+
+from Adafruit_LSM303.instruments import Instrument, Inclinometer
+
+
+@ddt
+class TestInstrument(TestCase):
+    def setUp(self):
+        lsm303 = MagicMock()
+        self.instrument = Instrument(lsm303)
+
+    @data(
+        (0, 0, 0),
+        (1, 0, 0),
+        (1, 1, 45),
+        (0, 1, 90),
+        (-1, 0, 180),
+        (-1, -1, 225),
+        (0, -1, 270),
+        (1, -0.0000000000000001, 360),
+    )
+    @unpack
+    def test_vector_2_degrees(self, x, y, expected_degrees):
+        degrees = self.instrument.vector_2_degrees(x, y)
+        self.assertEqual(expected_degrees, degrees)