CSC 110 Final Exam. ID checked

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1 ID checked CSC 110 Final Exam Name: Date: 1. Write a Python program that asks the user for a positive integer n and prints out n evenly spaced values between 0 and 10. The values should be printed with 3 places following the decimal point. Invalid values shall print an error message instead. Here is an example with the input value 5. Enter a number: Write a Python function named mean. This function takes a single parameter, a list of integer values. It returns the arithmetic mean of the values in the list. For full credit, use only one loop and do not use any built-in functions. For extra-credit, create a second implementation using built-in functions. (Hint: the e-c one is two lines long, including the def line.) For example, mean([1, 2, 3, 4]) 2.5

2 CSC 110 Final Exam 2 Initials The following three (3) questions are related. 3. Write a Python function named word_count that takes one str parameter: the input filename. The function shall open the input file, read its contents, and print out the line count, word count, character count, and input filename (to standard output). This same text should be written into a log file named word_count.log. Each call to the word_count function adds a single line to word_count.log. (For extra credit, only open the file once per function call.) For example, if the input file is seuss.txt, the printed line should be: seuss.txt. seuss.txt (the newline character immediately follows the last letter in each line one fish two fish red fish blue fish I am Sam, Sam I am. Do you like green eggs and ham?

3 CSC 110 Final Exam 3 Initials 4. In the space below, update the module to include a testing main function that calls your function. For the input file, use seuss.txt. The testing main should run when the module itself is run, but not when the module is imported. 5. There are exceptions (errors) that could possibly occur when running this function. Describe the conditions that could cause errors. There is no need to write handling code in your function for these errors. For extra-credit, list the Python keywords that would be used to handle these exceptions. 6. Which of the following is true about the global keyword? (Mark with T or F.) The global keyword makes it possible for a function to use the value of a global variable. The global keyword creates a global variable even if the variable is not named outside of any function. The global keyword can only be used outside of functions. The global keyword is used to create Python constants. The global keyword creates a variable that can be shared between different Python programs. 7. Write a Python function that takes two parameters, r and h, that returns the volume of a right circular cone of radius r and height h. You may assume that r and h are floats. volume = ⅓π r² h

4 CSC 110 Final Exam 4 Initials The following four (4) questions are related. 8. Complete the code to draw following window. Each of the four figures is 100x100 pixels. The yellow background is 240x240 pixels overall. The borders of the magenta square, the cyan circle, and the green square are 5 pixels wide. The lines in the red > are 12 pixels wide. Unless otherwise given, assume the color is black. (This can be done in less than 10 additional lines of code). import Gui3 win = Gui3.Gui() canvas = win.ca(250, 250) win.mainloop() 9. What is the effect of the first line of code? import Gui3 10. What is the effect of the last line of code? win.mainloop()

5 CSC 110 Final Exam 5 Initials 11. How would the code have to change, if it all, if the first line were rewritten as: from Gui3 import Gui 12. Tuples in Python are described as immutable. What does this term mean? What is the corresponding mutable structure in Python? For extra credit, give an example of what immutability allows/prohibits when working with tuples in Python. For the following 4 questions, consider the following declaration: text = 'widescreen' 13. Write Python code to get the letter r from the string text. 14. Write Python code to get the letter sequence ides as a single unit from the string text. (Extra credit: what is the term for this process.) 15. Write Python code to create the string wren, using the fewest sections of the string text. 16. What is the value of the following expression: text[1::3] 17. Write a Python function that takes three parameters, a, b, and c, that returns the positive root of a quadratic equation: ax 2 + bx +c. You may assume a, b, and c are floats. b root b 2 4ac 2a

6 CSC 110 Final Exam 6 Initials 18. Briefly describe the differences between syntax errors and logical errors. Example can be very helpful here, but are not required. For the following 4 questions, consider the following code fragment: text = 'ab = a*b' for c in text: print(c, sep=' ', end='\n') for c in text: print(c, sep='\n', end=' ') print(text) 19. Give the output that will be printed by these lines of code. Use an underscore _ to indicate a space; an arrow to indicate a newline 20. How many visible characters (characters that have black in them) are output? 21. How many spaces are output? 22. How many newline characters are output?