Transcript 03. Modulesx

142-253 Computer
Programming
BSc in Digital Media, PSUIC
Aj. Andrew Davison, CoE, PSU Hat Yai Campus
E-mail: [email protected]
3. Modules
Using modules to give Python even more POWER
Look at built-in modules: random, math, turtle, winsound
Start turtle graphics.
Look at installing easygui using pip
Using easygui
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1. What is a Module?
A module is a program that adds extra features
to Python
 e.g. for 3D graphics, for writing games
There are lots of modules that come with Python
 called built-in or standard modules
It is easy to add more
 called third-party modules
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Python's Design
A small
language …
… plus lots
of modules
turtle
math
winsound
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2. Using the random Module
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List Modules Already in Python
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Help on any Modules using the
word "random"
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click on "modules"
Module Documentation
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Information on random
Look under 'r' in the Python Module Index
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3. The math Module
Function name
abs(value)
Description
Constant
Description
absolute value
e
2.7182818...
ceil(value)
rounds up
pi
3.1415926...
cos(value)
cosine, in radians
degrees(value)
convert radians to degrees
floor(value)
rounds down
log(value, base)
logarithm in any base
log10(value)
logarithm, base 10
max(value1, value2, ...) larger of two (or more) values
min(value1, value2, ...) smaller of two (or more) values
radians(value)
convert degrees to radians
round(value)
nearest whole number
sin(value)
sine, in radians
sqrt(value)
square root
tan(value)
tangent
import math
or
from math import *
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Information on math
Look under 'm' in the Python Module Index
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4. The turtle Module
 The turtle moves about in a drawing window with a pen
for drawing lines.
 The turtle can be told to turn a number of degrees,
move a distance, move to a new position, and change
its pen's color and line width
 If the turtle’s pen is down, it draws a line; otherwise, it
moves without drawing
The Turtle Drawing Window
 The turtle is an icon
 Initial position: (0, 0)
 Initial direction: East (0°)
 Color: black
 Line width: 1 pixel
 Pen: down (ready to draw)
90°
x-axis
(0,0)
180°
0°
y-axis
270°
Create a Turtle
>>> from turtle import Turtle
>>> sleepy = Turtle()
Tell Python to add the
Turtle command to its
built-in commands
Some turtle Commands
home()
# Return to (0, 0) and 0° (east)
down()
# Enable drawing
up()
# Disable drawing
forward(distance)
# Go distance in current direction
goto(x, y)
# Go to (x, y)
left(degrees)
# Add degrees to current direction
setheading(degrees)
# Make degrees the new direction
width(width)
# Set width of pen in pixels
color(color)
# Red, green, blue, etc.
Move a Distance
>>> from turtle import Turtle
>>> sleepy = Turtle()
>>> sleepy.forward(50)
Move 50 pixels in the current direction.
There's also a backward() command.
Turning Left or Right
A turtle can turn left or right by a number of
degrees
 e.g. sleepy.left(45)
This angle is offset from the turtle's current
forward direction.
left(45)
forward
left(45)
forward
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Tell the turtle to draw a square
Square.py
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Draw a House
House.py
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A Blue Equilateral Triangle
Triangle.py
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Why those Angle?
Why does the square need 4 turns of 90*?
Why does the triangle need 3 turns of 120*?
Look for a pattern...
 4 * 90 == 3 * 120
== 360 degrees
How would you get the turtle to draw a fivesided shape (a pentagon)?
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A Faster Turtle
Square.py
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Filling the Shape with Color
Square.py
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Drawing (Bits of) Circles
Circles.py
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Writing Text
HelloWorld.py
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goto(x,y)
Also used in setpos(x,y)
The usual turtle window has
-200 ≤ x ≤ 200 and
-150 ≤ y ≤ 150
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Print Information about the Turtle
>>> from turtle import Turtle
>>> sleepy = Turtle()
>>> sleepy.goto(0, 50)
>>> print(sleepy.position(), sleepy.pencolor(), \
sleepy.heading(), sleepy.isdown())
(0.00,50.00) black 0.0 True
Information on turtle
Look under 't' in the Python Module Index
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6. Windows Sound: winsound
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Have you seen Star Wars?
Run the programs:
 March.py
 playSound.py
Python Gangnam Style:
 Gangnam.py
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7. Getting More Modules
https://pypi.python.org/pypi
I'll search for "GUI"
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lots more off the bottom of this picture
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the "easygui" looks good; click on it for
lots more details
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Info on easygui
The easygui webpage:
 http://easygui.sourceforge.net/
 you can also download easygui from there
 then use pip on the downloaded zip file
An easygui tutorial:
 http://www.ferg.org/easygui/tutorial.html
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8. Installing a PyPI Module
Use the pip program that comes as part of the
Python download.
Use it from the Command window.
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Use pip to Search PyPI
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Use pip to Install easygui
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More pip commands
pip help
 gives help on using pip
pip list
 lists the extra (thitd-party) modules that you have
added to Python
pip install <downloaded file>
 installs a module that you've downloaded yourself
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9. Use easygui in Python
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Use easygui with Less Typing
Tell Python to add all the
easygui commands to
Python's built-in commands
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Getting the "OK" Input
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Dialog Box with Buttons
IceButtons.py
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(Ugly) Choice Box
IceChoice.py
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Text Input
IceEnter.py
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Response
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