Karel's Built in Commands

move()

turn_left()

put_ball()

take_ball()

Functions

Writing a function is like teaching karel a new word.

Naming Functions: You can name your functions whatever you want, but you can't have spaces in the function name.

Remember that commands in functions must be indented one level

def turn_right():
	turn_left()
	turn_left()
	turn_left()

def turn_around():
	turn_left()
	turn_left()

def your_function_name():
  # Code that will run when you make a call to
  # this function.

Calling a Function

You call a function to tell the computer to actually carry out the new command.

# Call the turnn_around() function once
turn_around()

# Call the turn_right() function 2 times
turn_right()
turn_right()

Conditional Statements

if condition:
  #code that will run if the condition is true

if condition:
  #code that will run if the condition is true
else:
  #code that will run if condition is not true

Example of if statements

if front_is_clear():
  move()

if balls_present():
  take_ball()
else:
  move()

Karel Conditions

front_is_clear()
left_is_clear()
right_is_clear()

facing_north()
facing_south()
facing_east()
facing_west()

balls_present()
			

front_is_blocked()
left_is_blocked()
right_is_blocked()

not_facing_north()
not_facing_south()
not_facing_east()
not_facing_west()

no_balls_present()
			

Loops

While Loops

while CONDITION:
  # Code that will run while the CONDITION is true.
  # Once the CONDITION is no longer true,
  # it will stop.

Example of while loops

# This moves Karel to a wall
while front_is_clear():
	move()

For Loops

for i in range(COUNT):
  # Code that will run 'COUNT' times

Example of for loops

# This puts down 10 balls */
for i in range(10):
	put_ball()

# This puts down five balls and moves after each one
for i in range(5):
	put_ball()
	move()

Comments

"""
A multi-line comment describes your code
to someone who is reading it.
"""

# Use single line comments to clarify code.

Slides and Notes

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Collaborate on this sandbox program!

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A collaborative program is a program you can work on with a partner or group of people. The program shows up in all of your sandbox pages, and when any of you save code, it will save it for each person.

Embed Your Code On an HTML Page

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How to Use

Version 1: On Your Computer

1. Create a file called codehs.html on your desktop
2. Put the html below into the codehs.html file and save it
3. Now double click the file to open it in a web browser

Version 2: Online

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2. Put the html below into the codehs.html file and save it
3. Upload this file to the internet
4. Visit your web page

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