Professor: Peter Pacheco
Office: Harney 540
Phone: 422-6630
Email: domain: cs.usfca.edu, user: peter
Office Hours: M 4-5, W and F 10-11, and by appointment

TA: Haley Smith
Email: domain: usfca.edu, user: hrsmith
Office Hour: R 1:30-2:30

TA: Simon Piel
Email: domain: dons.usfca.edu, user: spiel
Office Hour: W 3:30-4:30

Class mailing list: The earlier instructions for joining the list were incorrect. Please send your preferred email address to the instructor, and he'll add you to the list. Once you're a member of the list you can also post messages by sending email to user cs110-03 in the domain cs.usfca.edu.

Course Syllabus (Here's a PDF Version.)

Programming Assignments:

• Programming Assignment 1 Here's a solution.
• Programming Assignment 2. Here's a solution.
• Programming Assignment 3. Here's a function that you can use to format floats in the histogram. Here's a program that you can use to generate input data for the histogram program. If you're going to try to get the extra credit, here are links to two programs from the text that may be useful: letters.py and polygon.py. Here's a solution.
• Programming Assignment 4. Here's some test data: dir0, dir1, dir2, dir3, dir4. Here's some sample output for printing the dictionaries created for the first four data sets: out0.txt, out1.txt, out2.txt, out3.txt. (Note: the order in which Python stores dictionary items is unpredictable. So your program may list the items in a different order.)
• Programming Assignment 5. Here's some code you can use. Here's a solution.

Lab Assignments:

• Assignment 1
  1. Part A (Nothing to turn in.)
  2. Part B (Add lab1b.py to your SVN repository.)
• Assignment 2.
  1. Part A: modify the final average program so that it takes as input all the scores except the final exam score. It also takes as input the desired final average. From this information it computes the score needed on the final exam to get the desired grade. This should be submitted to the l2 directory of your SVN repository as exam_score.py. Here's a solution.
  2. Part B: modify your solution to Part A so that it uses a function to compute the weighted average of the student's scores prior to the final exam. Use the value computed by this function to find the grade needed on the final exam in order to get the desired grade. Here's a partial solution Here's a solution.
• Assignment 3. All parts are due on Monday, September 19.
  1. Part A: Write a Python program that reads three lines of input. The first and third lines are numbers. The second line is an arithmetic operator (+, -, *, /). After reading the three lines, and converting the first and third to floats, the program should call a function that carries out the indicated operation and returns the result. When the call returns, the program should print the result. For example, if the user entered

              17 
              /
              2
           

     The program should print something like this

              The result is 8.5
           

     Here's a solution.
  2. Part B: Modify your solution to Part A so that it accepts input (number, operation, number) and prints the result until the user enters an 'x' for the operation. Here's a solution.
  3. Part C: Modify the average program so that it also finds and prints the variance and standard deviation of the user-input numbers. The variance can be calculated using the formula:

              sum_sq = val1**2 + val2**2 + . . . + valN**2
              variance = (sum_sq - N*average**2)/(N-1)
           

     The standard deviation is the square root of the variance. Be sure to check whether N-1 is 0 before doing the division. Here's a solution.
• Assignment 4. All parts are due on Friday, September 23.
  1. Part A. Fix the bug in the program that prints a triangle of asterisks. Then modify the program so that it prints the triangle ``upside down'': longest row first, then next longest row, etc. Only turn in the second program. Here's a solution
  2. Part B. Write a program that uses the TurtleWorld module to draw a regular polygon with n sides. The user will enter the number of sides and the length of the sides. Here's a solution
• Assignment 5. All parts are due on Friday, September 30.
  1. Part A. Use the random walk program as the basis for a program that draws a collection of randomly located circles with random radii. Let the user enter the delay between moves, the number of circles and the maximum radius (which you can assume is less than or equal to 50). Here's a solution.
  2. Part B. This program is an attempt to implement Newton's method. However, it doesn't check on the number of passes through the while loop. So it could enter an infinite loop. Modify it so that it gets from the user the maximum allowable number of passes, and checks this in the while statement. Here's a solution.
  3. Part C. Write a program that sorts the characters in a string into increasing alphabetic order. For example, if the string is "peter", then the program should create the new string "eeprt". You should assume that the only characters in the string are lowercase letters. Here's a solution.
• Assignment 6. All parts are due on Friday, October 14.
  1. Part A. Write a Python function del_char that deletes all occurrences of a character from a string. The parameters should be the character to delete and the string. The function should return a new string that's identical to the string parameter except the character is deleted. For example if the character is 'e' and the string is "peter", then the function should return the string "ptr". Use your function in a program that gets a string and a character from the user and prints the string with the character deleted. Here's a solution.
  2. Part B. Modify the sort_list function in the selection sort program so that it uses bubble sort. Here's a solution.
• Assignment 7. All parts are due on Friday, October 21.
  1. Part A. Modify the insertion sort program so that it sorts the input list in decreasing order. Here's a solution.
  2. Part B. Write a Python program that uses a recursive function to compute Fibonacci numbers. Input will be a nonnegative int n, output should be the nth Fibonacci number. Here's a solution
  3. Part C. Write a Python program that uses a recursive function to reverse a string that's input by the user. For example, if the user inputs "recursive", the program should print "evisrucer". Your program should not use any for or while statements. Here's a solution.
• Assignment 8. All parts are due on Monday, October 31.
  1. Part A. Write a recursive version of the regular polygon program. When the program ends the turtle should return to the same position and have the same direction that it had when the program started (center of window facing right). Your program should not use any for or while statements. Here's a solution.
  2. Part B. Write a Python program that stores information on a musician or musical group as a dictionary. The program should prompt the user for the name of the musician or group. It should also prompt the user for a list of the musician's songs. The information on each song should include the song's title, year, and length (in seconds), and this information should also be stored as a dictionary. When the user has finished entering information, the program should print the information he or she entered.
  3. Part C. Modify your solution to Part B so that after creating the database, it gives the user four options: Add a new song to the musician's song dictionary, delete a song from the musician's song dictionary, print information on a song -- its length and year --, and quit. Your program should prompt the user for a single character -- 'a', 'd', 'p', 'q'-- and it should continue prompting for and executing the user's commands until he or she types 'q'. Here's a solution to parts B and C.
• Assignment 9. All parts are due on Friday, November 4.
  1. Part A. Add the remaining reverse lookups to the movie database program (movie_d_use.py, movie_db.py, and movie_db1.py). Your program should find all movies made in a user-specified year, all movies made by a user-specified director, and all movies with a user-specified rating. Here's a solution.
  2. Part B. Use pickle and Python files to modify the musician database program so that it has options to write the database to a file and to read the database from a file. (See the movie database program for an example.) Here's a solution.
• Assignment 10. All parts are due on Friday, November 11.
  1. Part A. Add a depth-first search function to the program that reads and prints a square matrix. Your depth-first search function should print the number of each vertex when the vertex is "visited." Here's a solution.
  2. Part B. Write a Python program that will build a list of the ``words'' in an HTML file in this directory. Input to the program will be the name of the html file. Output should be a list of all strings that are not part of an HTML tag. For example, the words in virions.html are

                 virions, righties, mongos, ashy, trowing, manioca
           

     (Note that the title, virions, should be included in the list.) Here's a solution.
  3. Part C. Write a Python program that takes as input a ``root'' URL (e.g., http://cs.usfca.edu/~peter/cs110/dir) and the name of one of the files in this directory. It should open the file and create a list of absolute URLs for all of the links in the file. For example, if the root URL is http://cs.usfca.edu/~peter/cs110/dir and the input file is ariette.html then it should build the list

               http://cs.usfca.edu/~peter/cs110/dir/sorcerer.html
               http://cs.usfca.edu/~peter/cs110/dir/manioca.html
           

     Note: your program doesn't need to access the internet, just read the input, open the file, create the list, and print the list. Here's a solution.
• Assignment 11. All parts are due on Friday, December 2.
  1. Part A. Write a driver program for the sort_by_length function taken from Section 12.7 of the text. Your program should read in a list of words, one word per line. End of input will be indicated by an empty word (enter a carriage return). It should then sort the list by word length, and print the resulting list, one word per line. Here's a solution.
  2. Part B. Add functions deal_hands and print_hands to the code in the cards program. The first function should deal one card at a time to each player until each player has two cards. The second function should print out the cards in each hand. Here's a solution.
• Assignment 12. All parts are due on Monday, December 5.
  1. Part A. Write a gen_world function that can be used with the Life program. Its arguments are the number of rows and columns in the world, and a probability p (a float between 0 and 1). Use the random function from the random module to generate a random float for each cell in the world. If the random float is less than p, the cell should be alive. Otherwise it should be vacant. Include a driver for the function that gets the number of rows and columns and the probability p from the user. It should print the world returned by gen_world. You can use the life code that we've written so far in class. For a solution see the complete life program.
  2. Part B. Write a somethings_alive function that can be used in the Life program. Its arguments are the world and the number of rows and columns in the world. It should return True if there's at least one living cell. Otherwise it should return False. Include a driver for the function: it should get the number of rows and columns and the initial configuration from the user. It should print the world and the result of the call to somethings_alive. You can use the life code that we've written so far in class. For a solution see the complete life program.

Code Examples:

• Convert Celsius to Fahrenheit
• Find final average in CS 110
• Find an amount invested at simple interest
• Find an amount invested at compound interest
• Some programs that convert a single character Roman numeral into a Hindu-Arabic numeral
  • This version does no error handling
  • This version returns None if it finds erroneous input
  • This version exits if it finds erroneous input
  • This version accepts lower case as well as upper case characters
  • This version prints a message and asks for new input if the original input was incorrect
  • This version enters a loop if the input is incorrect.
• Running sum programs
  • Find the sum of a user-input list of numbers.
  • Find the average of a user-input list of numbers.
• Print patterns of asterisks
  • Print a row of asterisks using a while loop.
  • Print a row of asterisks using a for loop.
  • Print a rectangle of asterisks using nested for loops.
  • Print a rectangle of asterisks using nested while loops.
  • Print a rectangle of asterisks using nested while loops and a function for a row of asterisks.
  • Print a rectangle of asterisks using nested for loops and a function for a row of asterisks.
  • Print a triangle of asterisks using nested for loops and a function for a row of asterisks. This version has a bug.
• TurtleWorld Graphics
  • Draw a square with sidelength 100
  • Draw a square with user-specified sidelength
  • Draw an equilateral triangle with user-specified sidelength
  • Draw a regular polygon with user-specified sidelength and number of sides.
  • Draw a circle with user-specified radius.
  • Draw a random walk in which the path is always vertical or horizontal.
• Solving Equations
  • This program attempts to implement Newton's method, but it could have problems with an infinite loop.
• Strings
  • This program counts the number of times a character appears in a string.
  • This program finds the character that appears most often in a string.
• More Roman Numerals
  • A buggy program for converting a Roman Numeral to a Hindu-Arabic number.
  • A program for converting a Roman Numeral to a Hindu-Arabic number. This version fixes the bug in the previous version.
  • A program for converting a Roman Numeral to a Hindu-Arabic number. This version handles the final character outside the loop.
  • A program for converting a Roman Numeral to a Hindu-Arabic number. This version also converts the first character before the loop.
  • A program for converting a Roman Numeral to a Hindu-Arabic number. This version adjusts the subscripts.
  • A program for converting a Roman Numeral to a Hindu-Arabic number. This version handles erroneous input characters.
• Selection sort
  • A buggy program that tries to sort a list of ints.
  • A buggy program that tries to sort a list of ints. This version prints the list as it's changed by the program.
  • A buggy program that tries to sort a list of ints. This version attempts to swap two elements in the list.
  • A program that sorts a list of ints.
  • A program that sorts a list of ints. This version eliminates an unnecessary pass through the main for loop.
• Insertion sort
  • A buggy program that tries to sort a list of ints using insertion sort.
  • A program that sorts a list of ints using insertion sort.
• A program that looks at what happens when a function changes its parameters.
• Recursion
  • A buggy program that attempts to use recursion to print hello repeatedly.
  • A program that uses recursion to print hello repeatedly.
  • A buggy program that attempts to use recursion to add the first n positive ints.
  • A program that uses recursion to add the first n positive ints.
  • A program that uses recursion to add the first n positive ints. This version prints out where the program is in the sequence of recursive calls.
  • A program that uses binary search to search a sorted list. This version has a bug.
  • A program that uses binary search to search a sorted list.
  • A program that compares the performance of binary and linear search.
  • A program that draws a Koch curve.
  • A program that draws a Koch curve that will extend across the window.
• Dictionaries
  • A program that stores information on a movie as a list.
  • A program that stores information on a movie as a dictionary.
  • A program that stores information on a movie as a dictionary. This version has create_movie_d function that takes the title as a parameter.
  • A program that allows the user to create a database of movies.
  • A program that allows the user to create a database of movies, modify the database, and get some information from the database.
  • A program that allows the user to create a database of movies, modify the database, and get some information from the database. This version reads and writes the database using basic file operations.
  • A program that allows the user to create a database of movies, modify the database, and get some information from the database. This version reads and writes the database using the pickle module.
  • A program that compares the performance of binary and linear searching and using a dictionary. This version prints the list, the dictionary, the keys to be searched, and the results of each search.
  • A program that compares the performance of binary and linear searching and using a dictionary. This version only prints run-times.
• Life
  • A program that plays John Conway's game of life.
  • Another program that plays John Conway's game of life. This version doesn't print a traceback if a user enters Ctrl-C
  • A function for reading in ints

Other Information:

• A list of topics for the first midterm
• A key to the first version of midterm 1.
• A key to the second version of midterm 1.
• A list of topics for the second midterm
• A key to the first version of midterm 2.
• A key to the second version of midterm 2.
• A list of topics covered since the second midterm
• Some useful information