Week 16 agenda -- last class and quiz

We'll have one last quiz, which will cover all the major Python concepts we've talked about:

• variables and types
• for loops
• lists
• conditionals
• working with files

You'll have to have all homework in by Thursday night.

Quiz examples

1. Recall that sys.argv is a list containing all the words you type on the command line. What does the following program do?

   import sys
   num = 1
   for x in sys.argv:
       print(num, x)
       num = num + 1
   

2. Fill in the definition of the following function so that it prints even if the input is an even number, and odd if the input is an odd number. The % operator can be used to compute the remainder when dividing one number by another -- for example, 11 % 3 gives 2, because 11 divided by 3 has remainder 2.

   def print_parity(x):
       ...
   

3. Explain in words (you don't have to write any code) how to write a program that reads a file, and then overwrites the file with the same contents except all in uppercase.

4. What is the value of x at the end of the following program?

   a = 1
   b = 2
   if a > b:
       x = a
   else:
       x = b
   

5. Write a function that takes 2 numbers as input and returns the largest of the 2 numbers.

6. Fill in the following function so that it takes as list of numbers as input, and returns a new list consisting of the original numbers that were positive.

   def positives(numbers):
       output = []
       for n in numbers:
          if ...:
              ...
       return ...
   

7. Define a function called triangle that prints a triangle of height n when given input n. For example, triangle(4) should print something like:

   *
   **
   ***
   ****