IT 116: Introduction to Scripting

IT 116: Introduction to Scripting
Homework 7

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, October 27th 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
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

This script will print a Celsius to Fahrenheit conversion table
The Celsius temperature must range between a minimum and a maximum temperature
The table must have the same format as the table in homework 5
Each temperature in the table must be aligned with the label in the header table

Specification

Your script must print two conversion tables
One from Fahrenheit to Celsius
The other from Celsius to Fahrenheit
You convert Fahrenheit to Celsius like this
```
Celsius = (Fahrenheit - 32) * 5/9
```
To go from Kelvin to Fahrenheit
```
Fahrenheit = Celsius * 9/5 + 32
```
The script must contain five functions
- get_int
- fahrenheit_to_celsius_table
- fahrenheit_to_celsius
- celsius_to_fahrenheit_table
- celsius_to_fahrenheit

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

fahrenheit_to_celsius_table

Header

def fahrenheit_to_celsius_table(min, max):

The function must print "Fahrenheit" and "Celsius" with a tab character in between
Underneath these labels should be a line of dashes
This is followed by a for loop creating Fahrenheit values between min and max
Inside the loop the function will print the Fahrenheit and corresponding Celsius values
The Fahrenheit value will be obtained by a call to fahrenheit_to_celsius

fahrenheit_to_celsius

Header
```
def fahrenheit_to_celsius(fahr):
```
The function computes the Celsius temperature
Using the value contained in the parameter fahr
It must convert this Celsius value into an integer
And return it

celsius_to_fahrenheit_table

Header

def celsius_to_fahrenheit_table(min, max):

The function must print "Celsius" and "Fahrenheit" with a tab character in between
Underneath these labels should be a line of dashes
This is followed by a for loop creating Celsius values between min and max
Inside the loop the function will print the Celsius and corresponding Fahrenheit values
The Fahrenheit value will be obtained by a call to celsius_to_fahrenheit

celsius_to_fahrenheit

Header
```
def celsius_to_fahrenheit(celsius):
```
The function computes the Fahrenheit temperature
Using the value contained in the parameter celsius
It must convert this Fahrenheit value into an integer
And return it

Test Code

Your script must contain the following statements

min_fahrenheit = get_int("Minimum Fahrenheit: ")
max_fahrenheit = get_int("Maximum Fahrenheit: ")
print()
fahrenheit_to_celsius_table(min_fahrenheit, max_fahrenheit)
print()  
min_celsius = get_int("Minimum Celsius: ")
max_celsius = get_int("Maximum Celsius: ")
print()
celsius_to_fahrenheit_table(min_celsius, max_celsius)

They should appear at the bottom of your script

Output

The output should look something like this

Minimum Fahrenheit: 30
Maximum Fahrenheit: 40

Fahrenheit	Celsius
-----------------------
30		-1
31		-1
32		0
33		1
34		1
35		2
36		2
37		3
38		3
39		4
40		4

Minimum Celsius: 0
Maximum Celsius: 10

Celsius	Fahrenheit
------------------
0	32
1	34
2	36
3	37
4	39
5	41
6	43
7	45
8	46
9	48
10	50

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

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.
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.
Remove the pass statement from fahrenheit_to_celsius_table.
Replace it with a statement that prints the labels "Fahrenheit" and "Celsius".
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.
Write a for loop that gives the loop variable fahr 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 fahr.
Run the script.
Fix any errors you find.
Add a second argument to the print statement in fahrenheit_to_celsius_table.
This argument will be a call to the function fahrenheit_to_celsius with fahr as the argument.
Remove the pass statement from fahrenheit_to_celsius.
Replace it with a statement that returns the parameter fahr.
Run the script.
You should see two values for fahr on each line.
Fix any errors you find.
Remove the return statement in fahrenheit_to_celsius.
Replace it with an assignment statement that gives the variable celsius the converted value of fahr.
You will do this using the formula
```
celsius = (fahr - 32) * 5/9
```
Turn the value of celsius into an integer with an assignment statement using round.
Return the value of celsius.
Run the script.
You should see both the fahr and celsius values on the same line.
Fix any errors you find.
Now you have to make sure the celsius values align with the "Celsius" label.
This can be done using the escape sequence for the tab character, \t.
Replace the space between "Fahrenheit" and "Celsius" in the label with \t.
Now we need to print fahr and celsius 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 fahr and celsius.
Then we can use concatenation to put \t between them.
Run the script.
Fix any errors you find.
Repeat steps 3 - 7 for the last two functions making appropriate changes.
Use the conversion formula
```
fahr = celsius * 9/5 + 32
```

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 Fahrenheit: 30
Maximum Fahrenheit: 40

Fahrenheit	Celsius
-----------------------
30		-1
31		-1
32		0
33		1
34		1
35		2
36		2
37		3
38		3
39		4
40		4

Minimum Celsius: 0
Maximum Celsius: 10

Celsius	Fahrenheit
------------------
0	32
1	34
2	36
3	37
4	39
5	41
6	43
7	45
8	46
9	48
10	50

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

$ python3 hw7.py
Minimum Fahrenheit: 30
Maximum Fahrenheit: 40

Fahrenheit	Celsius
-----------------------
30		-1
31		-1
32		0
33		1
34		1
35		2
36		2
37		3
38		3
39		4
40		4

Minimum Celsius: 0
Maximum Celsius: 10

Celsius	Fahrenheit
------------------
0	32
1	34
2	36
3	37
4	39
5	41
6	43
7	45
8	46
9	48
10	50

The text in blue is what the user enters