Chapter 10 - Summary¶

Chapter 10 included the following concepts from computing.

Loop Body - The statement or statements that are repeated in a loop. In Python indention is used to show the statements that are part of the body of a loop.
Total Turtle Trip Theorem - The total turtle trip theorem states that the turtle will draw a closed figure with n sides when the sum of the angles turned is a multiple of 360.
Turtle Geometry - Turtle Geometry is a book by Hal Abelson and Andrea diSessa that explores math using turtles.

Summary of Python Keywords and Functions¶

def - The def keyword is used to define a procedure or function in Python. The line must also end with a : and the body of the procedure or function must be indented 4 spaces.
for - A for loop is a programming statement that tells the computer to repeat a statement or a set of statements. It is one type of loop.
print - The print statement in Python will print the value of the items passed to it.
range - The range function in Python returns a list of consecutive values. If the range function is passed one value it returns a list with the numbers from 0 up to and not including the passed number. For example, range(5) returns a list of [0, 1, 2, 3, 4]. If the range function is passed two numbers separated by a comma it returns a list including the first number and then up to but not including the second number. For example, range(1, 4) returns the list [1, 2, 3]. If it is passed three values range(start,end,step) it returns all the numbers from start to one less than end changing by step. For example, range(0, 10, 2) returns [0, 2, 4, 6, 8].
while - A while loop is a programming statement that tells the computer to repeat a statement or a set of statements. It repeats the body of the loop while a logical expression is true.

The table below shows the turtle functions and procedures that we have covered so far.

Name	Input	Description
backward	amount	Moves the turle backward by the specified amount
color	colorname	Sets the color for drawing. Use ‘red’, ‘black’, etc
forward	amount	Moves the turtle forward by the specified amount
goto	x,y	Moves the turtle to position x,y
left	angle	Turns the turtle counter clockwise by the specified angle
pendown	None	Puts down the turtles tail so that it draws when it moves
penup	None	Picks up the turtles tail so that it doesn’t draw when it moves
pensize	width	Sets the width of the pen for drawing
right	angle	Turns the turtle clockwise by the specified angle
setheading	angle	Turns the turtle to face the given heading. East is 0, north is 90, west is 180, and south is 270.
shape	shape name	Takes a shape name as a string to use for the turtle. The allowed values are “arrow”, “turtle”, “circle”, “square”, “triangle”, and “classic”.
stamp	None	Leaves a copy of the turtle shape at the current location
Turtle	None	Creates and returns a new turtle object