e01 : Midterm Exam E01
|e01||true||Midterm Exam E01||Wed 10/25 12:30PM|
Midterm Exam E01
A link to the actual exam will appear here after the the exam is graded.
The page typos and hints will show any typo corrections or hints offered while the exam is in progress, along with a countdown clock showing the time remaining.
What is covered
- H00 through H05
- Textbook Chapter 1 through 4.1
- Lectures up to day of the exam
- lab00 through lab03
- Python numeric data types and expressions: int, float, bool
- Other types of data: str, list and tuple
- Python objects and classes, and the use of class constructors to create new objects
- Variables and assignment
- Python functions - difference between function definition and function call
- Difference between print vs return
- Ability to generalize a given function and trace through code involving functions
- Local vs. global variables
- Designing functions the test driven approach and the use of stub functions
- Turtle graphics
- for loops
- Writing an interactive program using input and print
- Using Python modules and creating your own module using the if
Links to past exams
Here are some exams from past offerings of CS8 that you can look at to get an idea of the style of exam questions I typically write.
Please note that this quarter we may have covered MORE MATERIAL or LESS MATERAL than the point at which midterm 1 was given in previous quarters. Also, these courses all used a different textbook, and there were different homeworks and different labs. So your exam may cover much more or much less material. Use these as guides for style of exam rather than precise content.
- E01: http://www.cs.ucsb.edu/~pconrad/cs8/10F/exams/E01/
- E02: http://www.cs.ucsb.edu/~pconrad/cs8/10F/exams/E02/actualExam
- E03: http://www.cs.ucsb.edu/~pconrad/cs8/10F/exams/E03/actualExam
- E01: http://www.cs.ucsb.edu/~pconrad/cs8/10M/exams/E01/
- E02: http://www.cs.ucsb.edu/~pconrad/cs8/10M/exams/E02/actualExam
- E03: http://www.cs.ucsb.edu/~pconrad/cs8/10M/exams/E03/actualExam
- E01: http://www.cs.ucsb.edu/~pconrad/cs8/09M/exams/E01/
- E01: Actual Exam http://www.cs.ucsb.edu/~pconrad/cs8/09M/exams/E01/actualExam/
- E01: Practice Exam 1 http://www.cs.ucsb.edu/~pconrad/cs8/09M/exams/E01/CS8_09M_E01_practiceExam_1.html
- E01: Practice Exam 1, partial answer key and discussion http://www.cs.ucsb.edu/~pconrad/cs8/09M/exams/E01/CS8_09M_E01_practiceExam_1_notes.html
- E02: http://www.cs.ucsb.edu/~pconrad/cs8/09M/exams/E02/
- E03: http://www.cs.ucsb.edu/~pconrad/cs8/09M/exams/E03/
ANSWER KEY FOR Fall 2010, E02, Question 2
>>> squared(7) 49 >>>
Answer: CAN’T TELL. If we name the two versions
squaredB and run them both, we see this:
>>> squaredA(7) 49 >>> squaredB(7) 49 >>>
Now, what about this one:
>>> for i in range (4): squared(i) 0 1 4 9 >>>
This one is much more subtle. As it turns out, the answer depends on whether you define the
squared function in the shell, interactively, or whether you define it in a file before you run!
Suppose you defined it in the shell, like this. Note that the
... characters are not what you type—those come up automatically when you hit return in the Python Shell while defining a function.
>>> def squaredA(x): ... return x * x ... >>> def squaredB(x): ... print(x * x) ... >>>
If you define the functions this way, then the answer is CAN’T TELL! See for yourself:
>>> for i in range(4): ... squaredA(i) ... 0 1 4 9 >>> for i in range(4): ... squaredB(i) ... 0 1 4 9 >>> squaredA(i)
BUT if you define the functions in a file, with
File => New File, then choose
Run Module and then type in exactly
the same thing at the Python prompt, you end up with DIFFERENT OUTPUT!
For example this file:
def squared(x): print( x * x) for i in range(4): squared(i)
produces this output:
>>> RESTART: /Users/pconrad/github/ucsb-cs8/Lecture7_0822/squaredA_vs_squaredB.py 0 1 4 9 >>>
But this file:
def squared(x): return x * x for i in range(4): squared(i)
produces this output (i.e. NO OUTPUT).
RESTART: /Users/pconrad/github/ucsb-cs8/Lecture7_0822/squaredA_vs_squaredB.py >>>
This is unsatisfying. But, it’s true. When function calls return a value and nothing is done with that value (i.e. it isn’t stored in a variable, it isn’t passed to another function), the result in the Python Prompt (i.e. the Python REPL) is that the value is printed. But inside a file, that value just disappears.
So, in the end, the answer to the question, as it appeared on the exam, is CAN’T TELL, because clearly the code was being typed in at the Python Prompt (Python REPL).
But, I have to confess that there was a moment when I thought the answer was B. If the code had appeared in a file, the answer would definitely have been B.
Ok, let’s move on.
>>> 2 * squared(3) 18 >>>
This one is easy. Must be A.
for i in range(4): print(squared(i))
This one must be B. NOTE that it does NOT produce any Python error messages (sometimes called “Python Vomit”.) Also note that there are two print statements involved here: the one inside the function definition and the one inside the code we are running.