Chapter 7, Problem 9PE

Program Plan Intro

Population data

Program plan:

• • Declare a function named “main()”. Inside the function,
  • ○ Use the “try…except” block to read the population from the file.
  • ○ Create a file object “fileObj” for the file “USPopulation.txt”
  • ○ Now, read the populations from the file and store it in “populationList” and close the file.
  • ○ Use a “for” loop to convert the populations into “float” type.
  • ○ Create an empty list “populationChange” to hold the changes in the population.
  • ○ Now, use the “for” loop to find the population change for the successive years and store it in “populationChange”.
  • ○ Call the function “max()” to find the greatest population change.
  • ○ Call the function “index()” to find the position of the greatest population change.
  • ○ Call the function “min()” to find the lowest population change.
  • ○ Call the function “index()” to find the position of the lowest population change.
  • ○ Then, call the function “sum()” to find the sum of the population changes in the “populationChange”.
  • ○ Find the average annual change.
  • ○ Now, print the average annual change, greatest population change year, and lowest population change year using the “print()” function.
  • ○ Handle the exceptions if any occurred using the “except” blocks.
• • In the last, call the function “main()” to execute the program.