Download COSC 235B Test 1: Computer Science Concepts and Python Programming - Prof. David A. Sykes and more Exams Computer Science in PDF only on Docsity!
Test 1: Chapters 1‐ 4
Name: ______________________________ Pledged: _________________________________
Answer all questions completely.
1. Match the best answer. (There are two extra answers in the right column.)
Computer science
A step‐by‐step process for achieving a desired result
A problem for which known algorithms to solve
them take too long to be of practical value
Notations for expressing computations in an exact
and unambiguous way
A set of values and operations on those values
In Python, must start with a letter or an underscore
Reflects the structure of constructs in a language
Reflects the meaning of constructs in a language
Intended for human readers of a program
Used to give a name to a value so it can be referred
to at other points in a program
A. variable
B. type
C. the study of what
can be computed.
D. syntax
E. semantics
F. programming
language
G. intractable
H. identifier
I. definite loop
J. CPU
K. comments
L. algorithm
M.
2. Complete the program given below according to what the comments specify
import string def main():
Get a name
name = raw_input("Enter your full name: ")
Print the name in the form First-initial. Last —e.g., B. Dunlap
main()
3. When the program shown below is executed, the result is as shown in the Python shell
window. Explain what the problem is and mark up the program to show how to fix the
problem.
Investment calculator
def main(): investment = input("Enter the initial investment: ") apr = input("Enter the APR: ") years = input("Enter the term of the investment (years): ")
Simulate the passing of years and accumulated interest
balance = float(investment) for year in range(years): balance = balance + (balance * apr) print "End of Year %2d: $%7.2" % (year, balance)
Display the ending amount of the investment
print "After %d years, an initial investment of $%0.2f at %0.1f"+ "interest yields $%0.2f." % (years, investment, apr*100, balance) main()
5. Using well chosen variable names and reasonable comments, write a program^1 to:
a. Prompt a user for the name N of a text file,
b. Prompt for some text T , and then
c. Display the number of lines in the text file named N and the number of occurrences of T
in the file. [Bonus: make the search for T case insensitive.]
For example, if a file foo.txt contains the text in
the box at the right and a user entered foo.txt
for N and pick for T , then the program would
determine there are 3 lines and 6 occurrences
of pick in the file.
The function count() should prove useful.
Function Meaning count(s, sub) Count the number of occurrences of sub in s (^1) By program I mean everything that would have to be typed into a .py file in order for Python to successfully run this code. This includes import statements and a call to main() if a function main() is defined. Peter Piper picked a peck of pickled peppers; If Peter Piper picked a peck of pickled peppers, How many pickled peppers did Peter Piper pick?
