Comments on Assignment/PS 3

The assignment was graded out of 40 points. (We will normalize the grades for the problem sets at the end.) There was only a software lab this week.

• State Machines = 20 points
  • Question 1 (Counter) = 2 points
  • Question 2 (Mod 4) = 2 points
  • Question 3 (Mod n) = 2 points
    A common error was using the input as the modulus instead of using n.
  • Question 4 (transduce) = 2 points
    transduce needs to return a list of the outputs generated by the state machine as it steps through its states.
  • Question 5 (delay state machine) = 2 points
  • Question 6 (make delay SM procedure) = 2 points
  • Question 7 (make double delay SM) = 2 points
  • Question 8 (Average SM) = 2 points
    • Average all the inputs seen
    • Check for divide-by-zero on the first output
    • The first output should be zero (since the initial state is zero)
    • Don't store every value ever seen.
  • Question 9 (SR Flip-Flop) = 2 points
    Make sure to test the flip-flop with all possible values.
  • Question 10 (Fibonacci) = 2 points
    The output sequence starts 1, 1, 2...
  
  
• Polynomial Class = 20 points
  • Question 11 (Init and str) = 2 points
  • Question 12 (Add) = 5 points
    • A common error was to modify one or both of the original polynomials (it's still possible to do this even if you return a new polynomial).
    • add needs to return a Polynomial object.
    • It's necessary to deal with the case where the polynomials are not of the same order (by padding or something similar).
  • Question 13 (Overloading +) = 1 points
  • Question 14 (Val) = 3 points
  • Question 15 (Multiply) = 6 points
    • Again, a common error was to modify one or both of the original polynomials.
    • multiply needs to return a Polynomial object.
  • Question 16 (Root finding) = 3 points
    • The root finder needs to deal with polynomials of degree greater than 3. Some people only dealt with linear, quadratic, and cubic polynomials.
    • When you return complex roots, you need to actually return a number. Concatenating a "j" (like this: (str(a) + "+" + str(b) + "j") ) does not make a number complex.