CSC111 Lab 6 2014

--D. Thiebaut (talk) 15:00, 3 March 2014 (EST)

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Old MacDonald's Farm

Old MacDonald's farm is a song (almost) all American kids learn at one point in their life. I certainly never heard it when I grew up in France, but I think most of you will be familiar with it. If you don't know it, this YouTube video will get you acquainted with it. :-)

The goal of this problem is for you to add a section to the program below so that it prints parts of the lyrics of the famous song using a for-loop and functions.

Here's the beginning program which you have to modify:

# start with four animals in the farm
farm = [ "horse", "pig", "dog", "cat" ]

# sing(): a function that simulates singing a refrain for the song
# using the animal name.     
def sing( word ):
     print( word )

# "sing" all the names of the animals
for animal in farm:
     sing( animal )

• Create the program in lab6.py and run it.

Challenge 1

• Modify the function so that the output looks like the lyrics of the song:

    And on his farm he had a horse, E-I-E-I-O
    
    And on his farm he had a pig, E-I-E-I-O
    
    And on his farm he had a dog, E-I-E-I-O
    
    And on his farm he had a cat, E-I-E-I-O

• Make sure there's a blank line between each line with an animal name.

Challenge 2

• Modify the function some more so that the output looks like the lyrics of the song:

    Old MacDonald had a farm, E-I-E-I-O
    And on his farm he had a horse, E-I-E-I-O
    Here a horse, there a horse, everywhere a horse!
    
    Old MacDonald had a farm, E-I-E-I-O
    And on his farm he had a pig, E-I-E-I-O
    Here a pig, there a pig, everywhere a pig!
    
    Old MacDonald had a farm, E-I-E-I-O
    And on his farm he had a dog, E-I-E-I-O
    Here a dog, there a dog, everywhere a dog!
    
    Old MacDonald had a farm, E-I-E-I-O
    And on his farm he had a cat, E-I-E-I-O
    Here a cat, there a cat, everywhere a cat!

Challenge 3

• Modify your program a third time, and introduce a new function that will receive 4 animals as parameters, and will call the function sing( ) for each one.
• Then call your new function and give it four animals, and it should "sing" the whole song for you.

Here is an outline of what your final program should look like (you have to figure out what to replace the ellipses with!)

def sing( word ):
     print( ... )
     print( ...  word ... )
     print( ... )

def singSong( animal1, animal2, animal3, animal4 ):
     sing( animal1 )
     sing( animal2 )
     sing( animal3 )
     sing( animal4 )


singSong( "horse" ... )  # add three more animals after horse...

Disney's Dwarves in Boxes

• We have seen before how to print the name of Disney's seven dwarves:

seven = [ "Sleepy", "Sneezy", "Bashful", "Happy", "Grumpy", "Dopey", "Doc" ]

for name in seven:
    print( name )

• We saw in class a function that puts a box around a string:

def box( string ):
    line = "+"  +  ("-"*len( string ) )  + "+" 
    print( line )
    print( "|" + string + "|" )
    print( line )
    print()

• Create a program that uses the code snipets above and prints the names of the 7 dwarves in boxes:

+------+
|Sleepy|
+------+

+------+
|Sneezy|
+------+

+-------+
|Bashful|
+-------+

+-----+
|Happy|
+-----+

+------+
|Grumpy|
+------+

+-----+
|Dopey|
+-----+

+---+
|Doc|
+---+

Minions, Theater Production, and Functions

• Review the games we played in class about directing a play with students who say sentences... This section asks you to write the code for more script.

Game 6

Here's a new game. Read it, figure out what the minions are supposed to do, and translate it into Python code.

• Student 1 ( sentence )
  • Get sentence
  • say the sentence in UPPERCASE

• Student 2 (sentence )
  • get sentence
  • say the sentence in lowercase

• Student 3 (sentence1, sentence2 )
  • get sentence1 and sentence2
  • ask Student 1 to say "shhhhhhh!"
  • ask Student 1 to say sentence1
  • ask Student 2 to say setnence2
  • ask Student 2 to say "thank you"

• Call Student 3 and pass "Welcome" and "to CSC111 Lab 6!"

To get you started, below is the implementation of Student1 in Python:

def student1( sentence ):
     print( sentence.upper() )

Chessboard

Something Different

• Paste the code below in Idle. Figure out what it does before running it. Then run it.

 isGood = True
 for i in range( 5 ):
	print( isGood )
	isGood = not isGood

We have seen how to modify integer variables inside for-loops. We can also use boolean variables and "flip" them every loop to make them have opposite values one loop to the next. This may come in handy at some point :-)

Printing a Simple Small Chessboard

• Copy/paste the program below in Idle:

def printBlock( visible ):
    if visible==True:
        print( "#", end="" )
    else:
        print( ".", end="" )

def printLine( visibility ):
    printBlock( visibility )
    printBlock( not visibility )
    printBlock( visibility )
    printBlock( not visibility )
    print()

printLine( True )

• Run the program.
• Figure out how it generated the line #.#. Make sure you understand how this happened.

• Now change the last line of the program and replace True by False.
• Observe the new output. Figure out how the program reverses the output to .#.#

Challenge 4

Modify the program (including the functions) so that the output becomes:

#.#.#.#.#.#.#.#.
.#.#.#.#.#.#.#.#
#.#.#.#.#.#.#.#.
.#.#.#.#.#.#.#.#
#.#.#.#.#.#.#.#.
.#.#.#.#.#.#.#.#
#.#.#.#.#.#.#.#.
.#.#.#.#.#.#.#.#

which represents an 8x8 chessboard where the while cells are represented by dots and the black cells by hash-tags.

Challenge 5

Same as Challenge 4, but make sure your program uses a for-loop to print the 8 symbols on each line, and a for-loop to print the 8 lines.

Submission

Submit your program to this URL: | http://cs.smith.edu/~thiebaut/111b/submitL6.php