These are extra exercises that you can work on if you've got extra time
at the end of the lab. Write your code in a file named extra.py
.
writeReport
writeReport
should have two parameters: a list of tuples which each
consist of a string followed by a number, and a string which is a
filename. It should open the target file, erase any old contents (this
happens automatically if you open in write mode) and write out the
strings and numbers from the report, one pair per line. The string should
come first, then a colon, then a space, and then the number. So for
example, if you call:
writeReport(
[("titanium", 4.507), ("iron", 7.874), ("copper", 8.96)],
"metals.txt"
)
Then the file 'metals.txt' should contain the following text:
titanium: 4.507
iron: 7.874
copper: 8.96
readReport
readReport
does the opposite of writeReport
: it reads data from a
file into a list of tuples. It should accept one argument, which is a
filename, and it must read information from that filename and return a
list of tuples, each consisting of a string followed by a number. The
format in the file will be the same as the format shown in writeReport
:
a string, then a colon followed by a space, and finally the associated
number. If you already got writeReport
working using the test above,
then calling:
readReport("metals.txt")
should return the following value:
[("titanium", 4.507), ("iron", 7.874), ("copper", 8.96)]
Hint: you can use the .split
method of
strings with an argument to specify what character or sequence of
characters should be the split point. For this part, using ": "
as the
split point is quite efficient.
swapFiles
swapFiles
should take two filenames as arguments, and it should swap
the contents of the files. This is not too hard, but it's a bit more
challenging than it might seem at first :)
listEvents
listEvents
should take a single argument which is a string naming a
file to read data from. It should read data from that file specifying
calendar events, and then print out a listing of each event in a modified
format.
The events.txt
and events2.txt
files each have data which lists
events as three comma-separated fields: an event name, a start time in
hour:minute format, and a duration as a floating-point number of hours.
The start times use hours in a 24-hour format, so 3 p.m. would be listed
as 15. If listEvents
is called like this:
listEvents("events.txt")
the table it prints should look like this:
CS 111 (9:30-10:30)
Major advising (11:00-12:00)
Department meeting (12:30-1:30)
Research time (15:30-17:00)
Home with baby (18:00-6:30)
Note that even after you've figured out how to extract information from the file and convert it to numbers, you will have to do some math to convert the duration-in-hours into an end-time... one strategy is to first convert the number of hours and minutes into a time-in-fractional-hours and then convert that back to hours-and-minutes afterwards.
Table of Contents
- Lab 8 Home
- Part 0: Warm-Up
- Part 1: Tests & List Comprehensions
- Part 2: File Exercises
- Part 3: Secret Message
- Extra: Additional Exercises
- Knowledge Check