Make the example code compatible with python3

.gitignore

@@ -1,3 +1,3 @@
 *.pyc
 settings.json
-
+.DS_Store

chapter10/robot.py

@@ -56,12 +56,12 @@ def convert_speed(self, speed):
 
     def set_left(self, speed):
         mode, output_speed = self.convert_speed(speed)
-        self.left_motor.setSpeed(output_speed)
+        self.left_motor.setSpeed(int(output_speed))
         self.left_motor.run(mode)
 
     def set_right(self, speed):
         mode, output_speed = self.convert_speed(speed)
-        self.right_motor.setSpeed(output_speed)
+        self.right_motor.setSpeed(int(output_speed))
         self.right_motor.run(mode)
 
     def stop_motors(self):

chapter10/servo_type_position.py

@@ -1,5 +1,6 @@
 from Raspi_MotorHAT.Raspi_PWM_Servo_Driver import PWM
 import atexit
+from builtins import input
 
 pwm = PWM(0x6f)
 # This sets the timebase for it all
@@ -33,6 +34,6 @@ def stop():
 import time
 
 while (True):
-    position = int(raw_input("Type your position in degrees (90 to -90, 0 is middle): "))
+    position = int(input("Type your position in degrees (90 to -90, 0 is middle): "))
     end_step = convert_degrees_to_pwm(position)
     pwm.setPWM(0, 0, end_step)

chapter11/avoid_behavior.py

@@ -1,3 +1,4 @@
+from __future__ import print_function
 from robot import Robot, NoDistanceRead
 from time import sleep
 

chapter11/robot.py

@@ -65,14 +65,14 @@ def set_left(self, speed):
         if not self.drive_enabled:
             return
         mode, output_speed = self.convert_speed(speed)
-        self.left_motor.setSpeed(output_speed)
+        self.left_motor.setSpeed(int(output_speed))
         self.left_motor.run(mode)
 
     def set_right(self, speed):
         if not self.drive_enabled:
             return
         mode, output_speed = self.convert_speed(speed)
-        self.right_motor.setSpeed(output_speed)
+        self.right_motor.setSpeed(int(output_speed))
         self.right_motor.run(mode)
 
     def stop_motors(self):

chapter11/simple_avoid_behavior.py

@@ -1,3 +1,4 @@
+from __future__ import print_function
 from robot import Robot, NoDistanceRead
 from time import sleep
 

chapter11/test_hcsr04.py

@@ -1,8 +1,9 @@
+from __future__ import print_function
 import time
 from gpiozero import DigitalInputDevice, DigitalOutputDevice
 
 # Setup devices, an input device and an output device, with pin numbers for the sensors.
-print "Prepare GPIO pins"
+print("Prepare GPIO pins")
 
 # Left sensor
 left_trigger = DigitalOutputDevice(17)
@@ -17,7 +18,7 @@
 right_trigger.value = False
 
 # wait a little, to iron out spurious responses.
-print "Warm up time"
+print("Warm up time")
 time.sleep(0.5)
 
 def make_measurement(trig_device, echo_device):
@@ -37,15 +38,15 @@ def make_measurement(trig_device, echo_device):
         pulse_start = time.time()
         # We ran out of time here.
         if pulse_start > time_out:
-            print "timed out - missed pulse start"
+            print("timed out - missed pulse start")
             return 100
 
     # Now we wait for the echo_device pin to stop being 1, going from high, to low, the end of the pulse.
     pulse_end = time.time()
     while echo_device.pin.state == 1:
         pulse_end = time.time()
         if pulse_end > time_out:
-            print "timed out - pulse end too long"
+            print("timed out - pulse end too long")
             return 100
 
     # The duration is the time between the start and end of pulse in seconds.
@@ -61,6 +62,6 @@ def make_measurement(trig_device, echo_device):
     # Make our measurements and print them
     left_distance = make_measurement(left_trigger, left_echo)
     right_distance = make_measurement(right_trigger, right_echo)
-    print "Left: ", left_distance, "cm", "Right:", right_distance
+    print("Left: ", left_distance, "cm", "Right:", right_distance)
     # Sleep a bit before making another.
     time.sleep(0.5)

chapter12/drive_distance_behavior.py

@@ -1,3 +1,4 @@
+from __future__ import print_function
 from robot import Robot, EncoderCounter
 from pid_controller import PIController
 import time

chapter12/drive_square_behavior.py

@@ -1,3 +1,4 @@
+from __future__ import print_function
 from robot import Robot, EncoderCounter
 from pid_controller import PIController
 import time
@@ -52,7 +53,7 @@ def drive_distances(bot, left_distance, right_distance, speed=80):
         set_secondary(secondary_speed + adjustment)
         secondary_encoder.set_direction(math.copysign(1, secondary_speed+adjustment))
         # Some debug
-        print "Primary c:{:.2f} ({:.2f} mm)\tSecondary c:{:.2f} ({:.2f} mm) t:{:.2f} e:{:.2f} s:{:.2f} adjustment: {:.2f}".format(
+        print("Primary c:{:.2f} ({:.2f} mm)\tSecondary c:{:.2f} ({:.2f} mm) t:{:.2f} e:{:.2f} s:{:.2f} adjustment: {:.2f}".format(
             primary_encoder.pulse_count, 
             primary_encoder.distance_in_mm(),
             secondary_encoder.pulse_count,
@@ -61,11 +62,11 @@ def drive_distances(bot, left_distance, right_distance, speed=80):
             error,
             secondary_speed,
             adjustment
-        )
+        ))
 
         # Stop the primary if we need to
         if abs(primary_encoder.pulse_count) >= abs(primary_distance):
-            print "primary stop"
+            print("primary stop")
             set_primary(0)
             secondary_speed = 0
 
@@ -79,11 +80,11 @@ def drive_arc(bot, turn_in_degrees, radius, speed=80):
     else:
         left_radius     = radius + half_width_ticks
         right_radius    = radius - half_width_ticks
-    print "Arc left radius {:.2f}, right_radius {:.2f}".format(left_radius, right_radius)
+    print("Arc left radius {:.2f}, right_radius {:.2f}".format(left_radius, right_radius))
     radians = math.radians(abs(turn_in_degrees))
     left_distance = int(left_radius * radians)
     right_distance = int(right_radius * radians)
-    print "Arc left distance {}, right_distance {}".format(left_distance, right_distance)
+    print("Arc left distance {}, right_distance {}".format(left_distance, right_distance))
     drive_distances(bot, left_distance, right_distance, speed=speed)
 
 bot = Robot()

chapter12/robot.py

@@ -75,14 +75,14 @@ def set_left(self, speed):
         if not self.drive_enabled:
             return
         mode, output_speed = self.convert_speed(speed)
-        self.left_motor.setSpeed(output_speed)
+        self.left_motor.setSpeed(int(output_speed))
         self.left_motor.run(mode)
 
     def set_right(self, speed):
         if not self.drive_enabled:
             return
         mode, output_speed = self.convert_speed(speed)
-        self.right_motor.setSpeed(output_speed)
+        self.right_motor.setSpeed(int(output_speed))
         self.right_motor.run(mode)
 
     def stop_motors(self):

chapter12/straight_line_drive.py

@@ -1,9 +1,10 @@
+from __future__ import print_function
 from robot import Robot
 from pid_controller import PIController
 import time
 
 bot = Robot()
-stop_at_time = time.time() + 60
+stop_at_time = time.time() + 5
 
 speed = 80
 bot.set_left(speed)
@@ -19,10 +20,10 @@
     # Get the speed
     adjustment = pid.get_value(error)
     right_speed = int(speed + adjustment)
-    print "left", left, \
-        "right", right, \
-        "right_speed:", right_speed, \
-        "error:", error, \
-        "adjustment: %.2f" % adjustment
+    print("left", left,
+        "right", right,
+        "right_speed:", right_speed,
+        "error:", error,
+        "adjustment: %.2f" % adjustment)
     # Appy it to the right motor
     bot.set_right(right_speed)

chapter12/test_distance_travelled.py

@@ -1,3 +1,4 @@
+from __future__ import print_function
 from robot import Robot
 import time
 import math
@@ -16,6 +17,6 @@ def ticks_to_mm(ticks):
 bot.set_right(90)
 
 while time.time() < stop_at_time:
-    print "Left:", ticks_to_mm(bot.left_encoder.pulse_count), \
-        "Right:", ticks_to_mm(bot.right_encoder.pulse_count)
+    print("Left:", ticks_to_mm(bot.left_encoder.pulse_count), \
+        "Right:", ticks_to_mm(bot.right_encoder.pulse_count))
     time.sleep(0.05)

chapter12/test_encoders.py

@@ -23,5 +23,5 @@ def when_changed(self):
 bot.set_right(90)
 
 while time.time() < stop_at_time:
-    print "Left:", left_encoder.pulse_count, "Right:", right_encoder.pulse_count
+    print("Left:", left_encoder.pulse_count, "Right:", right_encoder.pulse_count)
     time.sleep(0.05)