University of Toronto - Spring 2002
Department of Computer Science

Assignment 6
Loops
FAQ Page

March 12:
Question: I need a little clarification on this paragraph: "That class must include a toString method that has a return that produces a String equivalent to the following:
return "high temperature: " + high + "\nlow temperature: " + low;
Your variable names may be different from those used above. This toString method must be used to print the program output. "
I thought the output would be the day with the largest span and the day with the lowest span, and what the span is, is that what the paragraph says? because to me it seems like you just want the highest and lowest temperature... which doesn't make much sense... so i was wondering.
Answer: Yes all I want are the temperatures for the two days, NOT the temperature span or the number of the day. OK that may not make total sense (to a meteorologist). For the moment just think of its purpose as a 108 loops assignment. Please follow the instructions from the assignment: "The output is the high and low temperatures for the day with the maximum span, followed by the high and low temperatures for the day with the minimum span." And please use a toString method that includes the following statement:
return "high temperature: " + high + "\nlow temperature: " + low;

Question: Do I need to deal with blank lines?
Answer: No. There will not be blank lines in the test samples. Also don't worry about punctuation immediately preceeding an a or an. There will not be a test like the following: Here is 'a example.'

March 11:
Question: When I subtract two different (but apparently equal) expressions, I get a small difference. Why? and What do I do?
Answer: (This is what is called roundoff error. You will learn all about it in the 270 course next year.) You may lose digits of precision when doing operations because computers store a limited number of digits and computers store values in binary even though the values are entered in decimal form. We will test your program with values of limited precision so this should not be a problem.

Question: I drove myself crazy over this, until I discovered that Java thought that 1.3 - 1.0 is *NOT* the same as 0.7 - 0.4 (it thinks the first is larger). I read the "hints and tips" on roundoff, but it doesn't seem to clear this up.
Answer: Obviously the two differences above are equal. Sorry, I am not surprised that you were going crazy. To fix this problem include and use the following method in the part of your program that updates the day with the minimum temperature span and the day with the maximum temperature span.

March 6:
Question: Under Part A of Assignment 6 in the Details paragraph you mentioned "There are no prompts printed", does this mean you don't want a method that will prompt the user for the days of the month and the high and low temperatures?
Answer: Your program will have no output other than the final result. There will be no messages printed on the screen requesting input from the user.

Further clarification to a question from March 5:
As it says in the assignment: "In addition to your ArticleTester class you must have a class that stores and corrects a line of text." The intention is that your program reads a line of text, stores the line of text in an object, corrects it in that object and prints the corrected line. Of course to finish that line (if the line ends in an article) your program may have to read the next line. Your program then goes on to store, correct and print the next line, etc.

March 5:
Question: Can we store the months temperature data in an array and then compare?
Answer: No. Do your comparisons when you read a day's data then there is no need to waste space by storing all the data when all you need is to store a few current values.

Question: What am I supposed to do in Part 2? I could store all the input in one string.
Answer: No that is not the intention. Similar to the question about Part A above do your processing as you go along. By storing all the input in a single String you would probably lose the formating in the original text.
As it says in the assignment: "In addition to your ArticleTester class you must have a class that stores and corrects a line of text." The intention is that your program reads a line of text, stores the line of text in an object, corrects it in that object and prints the corrected line. Of course to finish that line (if the line ends in an article) your program may have to read the next line. Your program then goes on to store, correct and print the next line, etc.