From 98e43aba494f9503a5a33309323d504f629ef27e Mon Sep 17 00:00:00 2001
From: Oleg Kalachev <okalachev@gmail.com>
Date: Tue, 20 Oct 2020 11:31:16 +0300
Subject: [PATCH] docs: python 3 updates

---
 docs/en/aruco_marker.md    |  4 ++--
 docs/en/camera.md          |  2 +-
 docs/en/cli.md             |  2 +-
 docs/en/laser.md           |  2 +-
 docs/en/migrate22.md       |  2 +-
 docs/en/programming.md     |  4 ++--
 docs/en/ros.md             |  2 +-
 docs/en/simple_offboard.md | 10 +++++-----
 docs/en/snippets.md        |  2 +-
 docs/en/sonar.md           |  4 ++--
 docs/ru/aruco_marker.md    |  4 ++--
 docs/ru/camera.md          |  2 +-
 docs/ru/cli.md             |  2 +-
 docs/ru/laser.md           |  2 +-
 docs/ru/migrate22.md       |  2 +-
 docs/ru/programming.md     |  4 ++--
 docs/ru/ros.md             |  2 +-
 docs/ru/simple_offboard.md | 10 +++++-----
 docs/ru/snippets.md        |  2 +-
 docs/ru/sonar.md           |  4 ++--
 20 files changed, 34 insertions(+), 34 deletions(-)

diff --git a/docs/en/aruco_marker.md b/docs/en/aruco_marker.md
index c75568a4..7c1c218b 100644
--- a/docs/en/aruco_marker.md
+++ b/docs/en/aruco_marker.md
@@ -98,9 +98,9 @@ rospy.init_node('my_node')
 # ...
 
 def markers_callback(msg):
-    print 'Detected markers:':
+    print('Detected markers:'):
     for marker in msg.markers:
-        print 'Marker: %s' % marker
+        print('Marker: %s' % marker)
 
 # Create a Subscription object. Each time a message is posted in aruco_detect/markers, the markers_callback function is called with this message as its argument.
 rospy.Subscriber('aruco_detect/markers', MarkerArray, markers_callback)
diff --git a/docs/en/camera.md b/docs/en/camera.md
index 0308b6ed..a1d75325 100644
--- a/docs/en/camera.md
+++ b/docs/en/camera.md
@@ -138,7 +138,7 @@ def image_callback(data):
         (x, y, w, h) = barcode.rect
         xc = x + w/2
         yc = y + h/2
-        print ("Found {} with data {} with center at x={}, y={}".format(b_type, b_data, xc, yc))
+        print("Found {} with data {} with center at x={}, y={}".format(b_type, b_data, xc, yc))
 
 image_sub = rospy.Subscriber('main_camera/image_raw', Image, image_callback, queue_size=1)
 
diff --git a/docs/en/cli.md b/docs/en/cli.md
index 6f634f10..3db1fc1e 100644
--- a/docs/en/cli.md
+++ b/docs/en/cli.md
@@ -39,7 +39,7 @@ cat file.py
 Run `file.py` as a Python script:
 
 ```bash
-python file.py
+python3 file.py
 ```
 
 Reboot Raspberry Pi:
diff --git a/docs/en/laser.md b/docs/en/laser.md
index 283fd0c1..59dd1cb6 100644
--- a/docs/en/laser.md
+++ b/docs/en/laser.md
@@ -59,7 +59,7 @@ rospy.init_node('flight')
 
 def range_callback(msg):
     # Process data from the rangefinder
-    print 'Rangefinder distance:', msg.range
+    print('Rangefinder distance:', msg.range)
 
 rospy.Subscriber('rangefinder/range', Range, range_callback)
 
diff --git a/docs/en/migrate22.md b/docs/en/migrate22.md
index c788796a..07b4120f 100644
--- a/docs/en/migrate22.md
+++ b/docs/en/migrate22.md
@@ -19,7 +19,7 @@ python3 flight.py
 Python 3 has certain syntax differences in comparison with the old version. Instead of `print` *operator*:
 
 ```python
-print 'Clover is the best'
+print 'Clover is the best'  # this won't work
 ```
 
 use `print` *function*:
diff --git a/docs/en/programming.md b/docs/en/programming.md
index cbd04bc3..f85d3465 100644
--- a/docs/en/programming.md
+++ b/docs/en/programming.md
@@ -34,10 +34,10 @@ Read more in the [GPS connection](gps.md) article.
 
 > **Info** For studying Python programming language, see [tutorial](https://www.learnpython.org/en/Welcome).
 
-After you've configured your positioning system, you can start writing programs for autonomous flights. Use the [SSH connection to the Raspberry Pi](ssh.md) to run your scripts. In order to run a Python script use the `python` command:
+After you've configured your positioning system, you can start writing programs for autonomous flights. Use the [SSH connection to the Raspberry Pi](ssh.md) to run your scripts. In order to run a Python script use the `python3` command:
 
 ```bash
-python flight.py
+python3 flight.py
 ```
 
 Below is a complete flight program that performs a takeoff, flies forward and lands:
diff --git a/docs/en/ros.md b/docs/en/ros.md
index 6753a2dc..ecc1a3e9 100644
--- a/docs/en/ros.md
+++ b/docs/en/ros.md
@@ -63,7 +63,7 @@ An example of subscription to topic `/foo`:
 
 ```python
 def foo_callback(msg):
-    print msg.data
+    print(msg.data)
 
 # Subscribing. When a message is received in topic /foo, function foo_callback will be invoked.
 rospy.Subscriber('/foo', String, foo_callback)
diff --git a/docs/en/simple_offboard.md b/docs/en/simple_offboard.md
index 109c5545..fd372eb8 100644
--- a/docs/en/simple_offboard.md
+++ b/docs/en/simple_offboard.md
@@ -75,14 +75,14 @@ Displaying drone coordinates `x`, `y` and `z` in the local system of coordinates
 
 ```python
 telemetry = get_telemetry()
-print telemetry.x, telemetry.y, telemetry.z
+print(telemetry.x, telemetry.y, telemetry.z)
 ```
 
 Displaying drone altitude relative to [the ArUco map](aruco.md):
 
 ```python
 telemetry = get_telemetry(frame_id='aruco_map')
-print telemetry.z
+print(telemetry.z)
 ```
 
 Checking global position availability:
@@ -90,9 +90,9 @@ Checking global position availability:
 ```python
 import math
 if not math.isnan(get_telemetry().lat):
-    print 'Global position is available'
+    print('Global position is available')
 else:
-    print 'No global position'
+    print('No global position')
 ```
 
 Output of current telemetry (command line):
@@ -307,7 +307,7 @@ Landing the drone:
 res = land()
 
 if res.success:
-    print 'drone is landing'
+    print('drone is landing')
 ```
 
 Landing the drone (command line):
diff --git a/docs/en/snippets.md b/docs/en/snippets.md
index 90dcd652..b2cf1128 100644
--- a/docs/en/snippets.md
+++ b/docs/en/snippets.md
@@ -319,7 +319,7 @@ def flip():
     rospy.loginfo('finish flip')
     set_position(x=start.x, y=start.y, z=start.z, yaw=start.yaw)  # finish flip
 
-print navigate(z=2, speed=1, frame_id='body', auto_arm=True)  # take off
+print(navigate(z=2, speed=1, frame_id='body', auto_arm=True))  # take off
 rospy.sleep(10)
 
 rospy.loginfo('flip')
diff --git a/docs/en/sonar.md b/docs/en/sonar.md
index 48b5e16f..53c42a1a 100644
--- a/docs/en/sonar.md
+++ b/docs/en/sonar.md
@@ -83,7 +83,7 @@ pi.callback(ECHO, pigpio.FALLING_EDGE, fall)
 
 while True:
     # Reading the distance:
-    print read_distance()
+    print(read_distance())
 
 ```
 
@@ -104,7 +104,7 @@ def read_distance_filtered():
     return numpy.median(history)
 
 while True:
-    print read_distance_filtered()
+    print(read_distance_filtered())
 ```
 
 An example of charts of initial and filtered data:
diff --git a/docs/ru/aruco_marker.md b/docs/ru/aruco_marker.md
index fee1ffe5..bddda97d 100644
--- a/docs/ru/aruco_marker.md
+++ b/docs/ru/aruco_marker.md
@@ -110,9 +110,9 @@ rospy.init_node('my_node')
 # ...
 
 def markers_callback(msg):
-    print 'Detected markers:':
+    print('Detected markers:'):
     for marker in msg.markers:
-        print 'Marker: %s' % marker
+        print('Marker: %s' % marker)
 
 # Подписываемся. При получении сообщения в топик aruco_detect/markers будет вызвана функция markers_callback.
 rospy.Subscriber('aruco_detect/markers', MarkerArray, markers_callback)
diff --git a/docs/ru/camera.md b/docs/ru/camera.md
index 08ca25e9..9c5a4fd7 100644
--- a/docs/ru/camera.md
+++ b/docs/ru/camera.md
@@ -140,7 +140,7 @@ def image_callback(data):
         (x, y, w, h) = barcode.rect
         xc = x + w/2
         yc = y + h/2
-        print ("Found {} with data {} with center at x={}, y={}".format(b_type, b_data, xc, yc))
+        print("Found {} with data {} with center at x={}, y={}".format(b_type, b_data, xc, yc))
 
 image_sub = rospy.Subscriber('main_camera/image_raw', Image, image_callback, queue_size=1)
 
diff --git a/docs/ru/cli.md b/docs/ru/cli.md
index d8c80196..35ed33df 100644
--- a/docs/ru/cli.md
+++ b/docs/ru/cli.md
@@ -39,7 +39,7 @@ cat file.py
 Запустить Python-скрипт `file.py`:
 
 ```bash
-python file.py
+python3 file.py
 ```
 
 Перезагрузить Raspberry Pi:
diff --git a/docs/ru/laser.md b/docs/ru/laser.md
index 7b9c7623..ba54374e 100644
--- a/docs/ru/laser.md
+++ b/docs/ru/laser.md
@@ -59,7 +59,7 @@ rospy.init_node('flight')
 
 def range_callback(msg):
     # Обработка новых данных с дальномера
-    print 'Rangefinder distance:', msg.range
+    print('Rangefinder distance:', msg.range)
 
 rospy.Subscriber('rangefinder/range', Range, range_callback)
 
diff --git a/docs/ru/migrate22.md b/docs/ru/migrate22.md
index 8c3d6493..9e66e8c1 100644
--- a/docs/ru/migrate22.md
+++ b/docs/ru/migrate22.md
@@ -19,7 +19,7 @@ python3 flight.py
 Синтаксис языка Python 3 имеет определенные изменения по сравнения со второй версией. Вместо *оператора* `print`:
 
 ```python
-print 'Clover is the best'
+print 'Clover is the best'  # this won't work
 ```
 
 теперь используется *функция* `print`:
diff --git a/docs/ru/programming.md b/docs/ru/programming.md
index 8e13274c..3777f2a8 100644
--- a/docs/ru/programming.md
+++ b/docs/ru/programming.md
@@ -34,10 +34,10 @@
 
 > **Info** Для изучения языка программирования Python обращайтесь к [самоучителю](https://pythonworld.ru/samouchitel-python).
 
-После настройки системы позиционирования становится возможным написание скриптов для автономных полетов. Для выполнения скриптов [подключитесь в Raspberry Pi по SSH](ssh.md). Для того, чтобы запустить Python-скрипт, используйте команду `python`:
+После настройки системы позиционирования становится возможным написание скриптов для автономных полетов. Для выполнения скриптов [подключитесь в Raspberry Pi по SSH](ssh.md). Для того, чтобы запустить Python-скрипт, используйте команду `python3`:
 
 ```bash
-python flight.py
+python3 flight.py
 ```
 
 Пример программы для полета (взлет, пролет вперед, посадка):
diff --git a/docs/ru/ros.md b/docs/ru/ros.md
index 2704603e..ff11c2e8 100644
--- a/docs/ru/ros.md
+++ b/docs/ru/ros.md
@@ -63,7 +63,7 @@ foo_pub.publish(data='Hello, world!')  # публикуем сообщение
 
 ```python
 def foo_callback(msg):
-    print msg.data
+    print(msg.data)
 
 # Подписываемся. При получении сообщения в топик /foo будет вызвана функция foo_callback.
 rospy.Subscriber('/foo', String, foo_callback)
diff --git a/docs/ru/simple_offboard.md b/docs/ru/simple_offboard.md
index f2ef57f2..a535dee2 100644
--- a/docs/ru/simple_offboard.md
+++ b/docs/ru/simple_offboard.md
@@ -75,14 +75,14 @@ land = rospy.ServiceProxy('land', Trigger)
 
 ```python
 telemetry = get_telemetry()
-print telemetry.x, telemetry.y, telemetry.z
+print(telemetry.x, telemetry.y, telemetry.z)
 ```
 
 Вывод высоты коптера относительно [карты ArUco-меток](aruco.md):
 
 ```python
 telemetry = get_telemetry(frame_id='aruco_map')
-print telemetry.z
+print(telemetry.z)
 ```
 
 Проверка доступности глобальной позиции:
@@ -90,9 +90,9 @@ print telemetry.z
 ```python
 import math
 if not math.isnan(get_telemetry().lat):
-    print 'Global position is available'
+    print('Global position is available')
 else:
-    print 'No global position'
+    print('No global position')
 ```
 
 Вывод текущей телеметрии (командная строка):
@@ -307,7 +307,7 @@ set_velocity(vx=0.4, vy=0.0, vz=0, yaw=float('nan'), yaw_rate=0.4, frame_id='bod
 res = land()
 
 if res.success:
-    print 'Copter is landing'
+    print('Copter is landing')
 ```
 
 Посадка коптера (командная строка):
diff --git a/docs/ru/snippets.md b/docs/ru/snippets.md
index adaabe5d..ec70652a 100644
--- a/docs/ru/snippets.md
+++ b/docs/ru/snippets.md
@@ -337,7 +337,7 @@ def flip():
     rospy.loginfo('finish flip')
     set_position(x=start.x, y=start.y, z=start.z, yaw=start.yaw)  # finish flip
 
-print navigate(z=2, speed=1, frame_id='body', auto_arm=True)  # take off
+print(navigate(z=2, speed=1, frame_id='body', auto_arm=True))  # take off
 rospy.sleep(10)
 
 rospy.loginfo('flip')
diff --git a/docs/ru/sonar.md b/docs/ru/sonar.md
index 042530f5..7625fad6 100644
--- a/docs/ru/sonar.md
+++ b/docs/ru/sonar.md
@@ -83,7 +83,7 @@ pi.callback(ECHO, pigpio.FALLING_EDGE, fall)
 
 while True:
     # Читаем дистанцию:
-    print read_distance()
+    print(read_distance())
 
 ```
 
@@ -104,7 +104,7 @@ def read_distance_filtered():
     return numpy.median(history)
 
 while True:
-    print read_distance_filtered()
+    print(read_distance_filtered())
 ```
 
 Пример графиков исходных и отфильтрованных данных: