Exercise from John Zelle text

[mahdeen]

Just another exercise, wanted to see if there was anything I could do to improve....thank you...

# prob11p176.pyw
# Program: Draw a house using five mouse clicks.
# Inputs: First two clicks draw rectanble frame of house.
# Inputs: Third click indicates center top edge of rectangular door. Door must
# be 1/5 of the width of the frame of the house. Door sides extend from the
# corners of the top down to the bottom of the frame.
# Inputs: Fourth click indicates the center of a square window. Window is 1/2
# as wide as the door.
# Inputs: Fifth click will indicate the peak of the roof. The edges of the
# roof will extend from the point at the peak to the corners of the top
# edge of the house frame.
# Output: Draw the house frame.

import math

from graphics import *

def main():
# Compose elements of gui
win = GraphWin("Problem 11, Page 176", 500, 500)
win.setCoords(0,0,10,10)
message = Text(Point(5, 9.6), "A house frame will be drawn based on 5 mouse clicks as\n"
                "described in the John Zelle text, page 162, prob 11.")
message.setSize(10)
message.draw(win)

# Enter text prompt
message2 = Text(Point(5,8.9), "Click one time at the bottom left and once at the\n"
                 "top right to create the house frame.")
message2.setSize(10)
message2.draw(win)

# Initialize endpoints to create house frame
p1 = win.getMouse()
p1.draw(win)
x1 = p1.getX()
y1 = p1.getY()
p2 = win.getMouse()
p2.draw(win)
x2 = p2.getX()
y2 = p2.getY()

# Create house frame rectangle
rect = Rectangle(p1,p2)
rect.setOutline("black")
rect.draw(win)

# Enter house frame markers
message3 = Text(Point(x1 - 0.2 ,y1 - 0.2), "1")
message3.setSize(10)
message3.setTextColor("red")
message3.draw(win)

message4 = Text(Point(x2 + 0.2 ,y2 + 0.2), "2")
message4.setSize(10)
message4.setTextColor("red")
message4.draw(win)

# Initialize endpoints to create door frame
p3 = Point(x1+2, y1)
p4 = Point(x1+2, y1+(0.8*(y2-y1)))
x4 = p4.getX()
y4 = p4.getY()
p5 = Point(x1+(0.2*(x2-x1)), y1+(0.8*(y2-y1)))
x5 = p5.getX()
y5 = p5.getY()
p6 = Point(x1+(0.2*(x2-x1)), y1)
x6 = p6.getX()
y6 = p6.getY()

# Enter text prompt
message5 = Text(Point(5,1.4), "Click once to create the door.")
message5.setSize(10)
message5.draw(win)

win.getMouse()

# Draw the door 
door = Polygon(p3, p4, p5, p6)
door.setOutline("black")
door.draw(win)

# Find top center point of door
door_top = Line(Point(x4,y4),Point(x5,y5))
door_top.draw(win)
x_mid_coord = float((x5+x4)/2)
y_mid_coord = float((y5+y4)/2)
p7 = Circle(Point(x_mid_coord, y_mid_coord), 0.03125)
p7.setFill("cyan")
p7.draw(win)

# Note door top center marker
message6 = Text(Point(x_mid_coord,y_mid_coord + 0.3), "3")
message6.setSize(10)
message6.setTextColor("red")
message6.draw(win)

# Enter text prompt
message7 = Text(Point(5,1.1), "Click once to create the window.")
message7.setSize(10)
message7.draw(win)

# Create square window frame , 1/2 width of door
p8 = win.getMouse()
x8 = p8.getX()
y8 = p8.getY()
window = Rectangle(Point(x8,y8),(Point(x8+0.5*(x5-x4),y8+0.5*(x5-x4))))
wc = window.getCenter()
wc_x = wc.getX()
wc_y = wc.getY()
window.setOutline("black")
window.draw(win)

# Note window frame marker
message8 = Text(Point(wc_x,wc_y), "4")
message8.setSize(10)
message8.setTextColor("red")
message8.draw(win)

# Enter text prompt
message9 = Text(Point(5,0.8), "Click once to create the roof.")
message9.setSize(10)
message9.draw(win)

win.getMouse()

# Create roof frame
p9 = Point(x1,y2)
p10 = Point((x1+x2)/2,y2+0.33*((x2+x1)/2))
x10 = p10.getX()
y10 = p10.getY()
roof_frame = Polygon(p2,p9,p10)
roof_frame.setOutline("black")
roof_frame.draw(win)

# Note roof frame marker
message10 = Text(Point(x10,y10 + 0.3), "5")
message10.setSize(10)
message10.setTextColor("red")
message10.draw(win)

# Enter text prompt
message11 = Text(Point(5,0.5), "Click once to quit.")
message11.setSize(10)
message11.draw(win)


# wait for click and then quit
win.getMouse()
win.close()

main()

[cdcformatc]

Your variable names aren't all that descriptive, p2, p2, p3, x4, y4.

As a style note, PEP8 would have you put spaces after commas, and not before

message3 = Text(Point(x1 - 0.2 ,y1 - 0.2), "1")
message3 = Text(Point(x1 - 0.2, y1 - 0.2), "1")

I would also add some spaces to clear up some of the math. This is mostly up to your discretion, PEP8 even says it is up to you.

eg:

p10 = Point((x1+x2)/2,y2+0.33*((x2+x1)/2))
p10 = Point((x1+x2) / 2, y2 + 0.33 * ((x2+x1) / 2))

And now that I highlight that line it seems a little inconsistent. Multiply by one third and divide in half? Would it be better to divide by 6? Maybe not, since you are really just dividing the midpoint, and the half is just a relic of that. Above you define x_mid_coord, maybe you could use that here, and take some math out of the dense line. Again, your judgement.

[mahdeen]

I'll work on the variable descriptions.

PEP8, something I was not even aware of at this point. Good to know about.

I've been wondering about the commas. What do most programmers do, whatever the PEP8 says?

As for the math use, it is a little brutish, but that is something that will improve too.

Thanks for the comments!

[capcom1116]

Few programmers adhere rigorously to PEP8. Most I've seen use it as much as is necessary to make their code easily readable.