• Due
• What You Need to Do
• Setup On Your Machine
• Specification
• Functions
• Test Code
• Output
• Suggestions
• Testing on Your Machine
• Copy the Script to Unix
• Testing the Script on Unix (Optional)

Due

Sunday, March 24th at 11:59 PM

What You Need to Do

• Create the script hw7.py
• Make sure it obeys the rules in Rules for Homework Scripts
• Make sure the script has a hashbang line and is executable
• Move it to an an hw7 directory on pe15.cs.umb.edu

Setup On Your Machine

• Open a text editor.
  I would suggest the text editor built into the program IDLE.
• Save the file as hw7.py

Specification

• Your script must print two conversion tables
• One from miles to kilometers
• The other from kilometers to miles
• You convert miles to kilometers like this

  kilometers = miles * 1.609344

• To go from kilometers to miles

  miles = kilometers / 1.609344

• The script must contain 5 functions
  • get_int
  • miles_to_kilometers_table
  • miles_to_kilometers
  • kilometers_to_miles_table
  • kilometers_to_miles

Functions

get_int

• Header

  def get_int(prompt):

• This function has one parameter, prompt, a string
• The function uses this prompt in a call to input to get a value
• It converts this value into an integer and returns the converted value

miles_to_kilometers_table

• Header

  def miles_to_kilometers_table(min, max):

• This function prints a miles to kilometers conversion table with miles values running from min to max
• Before printing the table, the function prints the labels "Miles" and "Kilometers", followed by a line of dashes
• The function prints each line of the table calling miles_to_kilometers to get the kilometer value
• The kilometer values should align with the "Kelvin" label

miles_to_kilometers

• Header

  def miles_to_kilometers(miles):

• This function converts a miles value to kilometers and returns that value
• The kilometers value must be an integer

kilometers_to_miles_table

• Header

  def kilometers_to_miles_table(min, max):

• This function prints an kilometers to miles conversion table with miles values running from min to max
• Before printing the table, the function prints the labels "Miles" and "Kilometers", followed by a line of dashes
• The function prints each line of the table calling kilometers_to_miles to get the kilometers value
• The miles values should align with the "Miles" label
• See the example below

kilometers_to_miles

• Header

  def kilometers_to_miles(km):

• This function converts a kilometers value to miles and returns that value
• The miles value must be an integer

Test Code

• Your script must contain the following statements

  min_miles = get_int("Minimum Miles: ")
  max_miles = get_int("Maximum Miles: ")
  print()
  miles_to_kilometers_table(min_miles, max_miles)
  print()
  min_km = get_int("Minimum Kilometers: ")
  max_km = get_int("Maximum Kilometers: ")
  print()
  kilometers_to_miles_table(min_km, max_km)

• They should appear at the bottom of your script

Output

• The output should look something like this

  Minimum Miles: 1
  Maximum Miles: 10
  
  Miles	Kilometers
  -------------------
  1		2
  2		3
  3		5
  4		6
  5		8
  6		10
  7		11
  8		13
  9		14
  10		16
  
  Minimum Kilometers: 10
  Maximum Kilometers: 20
  
  Kilometers	Miles
  ----------------------
  10			6
  11			7
  12			7
  13			8
  14			9
  15			9
  16			10
  17			11
  18			11
  19			12
  20			12

• The text in blue is what the user enters

Suggestions

• Write this script in stages
• Test your script at each step
• Print the steps below
• And check them off as you finish each one

1. Copy only the function headers for the five functions listed above into your script file.
   Under each header, write pass.
   Make sure this statement is indented.
   Run the script.
   Fix any errors you find.
2. Remove the pass statement from get_int.
   Replace it with an assignment statement that uses input to give the variable number a value.
   Use the parameter prompt as the argument to input.
   Use an assignment statement to convert number into an integer.
   Return number.
   Copy the test code to the bottom of the script file.
   Comment out all but the first two lines of the test code.
   Run the script.
   Fix any errors you find.
3. Remove the pass statement from miles_to_kilometers_table.
   Replace it with a statement that prints the labels "Miles" and "Kilometers".
   Then write a statement that prints a line of dashes, -.
   Uncomment the next two lines in the test code.
   Run the script.
   Fix any errors you find.
4. Write a for loop that gives the loop variable miles values from min to max.
   You will have to use range to do this, and be careful about the 2nd argument.
   Inside the loop print the value of miles.
   Run the script.
   Fix any errors you find.
5. Add a second argument to the print statement in miles_to_kilometers_table.
   This argument will be a call to the function miles_to_kilometers with miles as the argument.
   Remove the pass statement from miles_to_kilometers.
   Replace it with a statement that returns the parameter miles.
   Run the script.
   You should see two values for miles on each line.
   Fix any errors you find.
6. Remove the return statement in miles_to_kilometers.
   Replace it with an assignment statement that gives the variable km the converted value of miles.
   You will do this using the formula

   km = miles * 1.609344

   Turn the value of km into an integer with an assignment statement using round.
   Return the value of km.
   Run the script.
   You should see both the miles and km values on the same line.
   Fix any errors you find.
7. Now you have to make sure the km values align with the "Kilometers" label.
   This can be done using the escape sequence for the tab character, \t.
   Replace the space between "Miles" and "Kilometers" in the label with \t.
   Now we need to print miles and km with \t in between.
   To make this work we will need to concatenate the three values.
   But numbers cannot be concatenated with strings.
   So we have to run the str string conversion function on both miles and km.
   Then we can use concatenation to put \t between them.
   Run the script.
   Fix any errors you find.
8. Repeat steps 3 - 7 for the last two function making appropriate changes.
   Use the conversion formula

   miles = km / 1.609344

Testing on Your Machine

• Open IDLE
• Use the Open command in IDLE to open hw7.py
• Run your script inside IDLE
• Your output should look something like this

  Minimum Miles: 1
  Maximum Miles: 10
  
  Miles	Kilometers
  -------------------
  1		2
  2		3
  3		5
  4		6
  5		8
  6		10
  7		11
  8		13
  9		14
  10		16
  
  Minimum Kilometers: 10
  Maximum Kilometers: 20
  
  Kilometers	Miles
  ----------------------
  10			6
  11			7
  12			7
  13			8
  14			9
  15			9
  16			10
  17			11
  18			11
  19			12
  20			12

• The text in blue is what you enter at the command line

Copy the Script to Unix

• Open FileZilla and connect to pe15.cs.umb.edu
• Go to your it116 directory
• Go to your hw directory
• Right-click in the whitespace inside the hw directory
• Enter hw7 in the dialog box
• Click and drag your script from the bottom left panel to the bottom right panel

Testing the Script on Unix (Optional)

• Connect to pe15.cs.umb.edu using an ssh client like putty.exe (Windows) or ssh (Mac)
• Go to the directory for this exercise

  cd  it116/hw/hw7

• Run this script

  python3 hw7.py

• You should see something like this

  Minimum Miles: 1
  Maximum Miles: 10
  
  Miles	Kilometers
  -------------------
  1		2
  2		3
  3		5
  4		6
  5		8
  6		10
  7		11
  8		13
  9		14
  10		16
  
  Minimum Kilometers: 10
  Maximum Kilometers: 20
  
  Kilometers	Miles
  ----------------------
  10			6
  11			7
  12			7
  13			8
  14			9
  15			9
  16			10
  17			11
  18			11
  19			12
  20			12

• The text in blue is what you enter at the command line

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