Exercises: Booleans and Conditionals

For the exercises, open up the booleans-and-conditionals directory in data-analysis-projects.

To answer questions 1 and 2, code your work in exercises01.py.

Assign the following variables for our space shuttle

Variable Name	Value
`engine_indicator_light`	red blinking
`space_suits_on`	True
`shuttle_cabin_ready`	True
`crew_status`	`space_suits_on` and `shuttle_cabin_ready`
`computer_status_code`	200
`shuttle_speed`	15000

Check your solution

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engine_indicator_light = "red blinking"
space_suits_on = True
shuttle_cabin_ready = True
crew_status = space_suits_on and shuttle_cabin_ready
computer_status_code = 200
shuttle_speed = 15000

Examine the code below. What will be printed to the console?

Use the value of engine_indicator_light defined above to answer this question.

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if engine_indicator_light == "green": 
   print("engines have started")
elif engine_indicator_light == "green blinking": 
   print("engines are preparing to start")
else:
   print("engines are off")

For questions 3 and 4, code in exercises02.py.

Write conditional expressions to satisfy the safety rules.

Use the variables defined from the table above to satisfy the rules listed below.

crew_status
- If the value is True, print "Crew Ready"
- Else print "Crew Not Ready"

Check your solution

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if crew_status:
   print("Crew Ready")
else:
   print("Crew Not Ready")

computer_status_code
- If the value is 200, print "Please stand by. Computer is rebooting."
- Else if the value is 400, print "Success! Computer online."
- Else print "ALERT: Computer offline!"

Check your solution

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if computer_status_code == 200:
   print("Please stand by. Computer is rebooting.")
elif computer_status_code == 400:
   print("Success! Computer online.")
else:
   print("ALERT: Computer offline!")

shuttle_speed
- If the value is > 17500, print "ALERT: Escape velocity reached!"
- Else if the value is < 8000, print "ALERT: Cannot maintain orbit!"
- Else print "Stable speed"

Check your solution

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if shuttle_speed > 17500:
   print("ALERT: Escape velocity reached!")
elif shuttle_speed < 8000:
   print("ALERT: Cannot maintain orbit!")
else:
   print("Stable speed.")

PREDICT

Do these code blocks produce the same result? Answer Yes or No.

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if crew_status and computer_status_code == 200 and space_suits_on:
   print("all systems go")
else:
   print("WARNING. Not ready")

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if crew_status != True or computer_status_code != 200 or not(space_suits_on):
   print("WARNING. Not ready")
else:
   print("all systems go")

For exercises 5 and 6, code in exercises03.py.

Monitor the shuttle’s fuel status.

Implement the checks below using if / elif / else statements. Order is important when working with conditionals, and the checks below are NOT written in the correct sequence. Please read ALL of the checks before coding and then decide on the best order for the conditionals.

If fuel_level is above 20000 AND engine_temperature is at or below 2500, print "Full tank. Engines good."
If fuel_level is above 10000 AND engine_temperature is at or below 2500, print "Fuel level above 50%. Engines good."
If fuel_level is above 5000 AND engine_temperature is at or below 2500, print "Fuel level above 25%. Engines good."
If fuel_level is at or below 5000 OR engine_temperature is above 2500, print "Check fuel level. Engines running hot."
If fuel_level is below 1000 OR engine_temperature is above 3500 OR engine_indicator_light is red blinking, print "ENGINE FAILURE IMMINENT!"
Otherwise, print "Fuel and engine status pending..."

Check your solution

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if fuel_level < 1000 or engine_temperature > 3500 or engine_indicator_light == "red blinking":
   print("ENGINE FAILURE IMMINENT!")
elif fuel_level <= 5000 or engine_temperature > 2500:
   print("Check fuel level. Engines running hot.")
elif fuel_level > 20000 and engine_temperature <= 2500:
   print("Full tank. Engines good.")
elif fuel_level > 10000 and engine_temperature <= 2500:
   print("Fuel level above 50%. Engines good.")
elif fuel_level > 5000 and engine_temperature <= 2500:
   print("Fuel level above 25%. Engines good.")
else:
   print("Fuel and engine status pending...")

Final bit of fun!
The shuttle should only launch if the fuel tank is full and the engine check is OK. However, let’s establish an override command to ignore any warnings and send the shuttle into space anyway!
1. Create the variable command_override, and set it to be true or false.
  If command_override is False, then the shuttle should only launch if the fuel and engine check are OK.
  If command_override is True, then the shuttle will launch regardless of the fuel and engine status.
2. Code the following if / else check:
  If fuel_level is above 20000 AND engine_indicator_light is NOT red blinking OR command_override is true print "Cleared to launch!"
  Else print "Launch scrubbed!"

Submitting Your Work

Commit and push your work to GitHub. Copy and paste the URL to your GitHub repository on the submission page for the exercises in Canvas.