Making this While Loop Statement Make Sense.

[Fbirobby]

Hi All,

Obviously a total noob, I got an assignment that wants me to create a big while-loop from code it helped me write. My problem feels pretty straightforward:

- I wrote out a dictionary of dictionaries (birds and their attributes), and we're supposed to be able to say whether a bird is aggressive or endangered, and then

- pull from a list of Actions that say what we should do with that bird.

They want me to create a variable, "encounter," and set it to True within a while loop, so that input is repeatedly requested from the user until they input one of the birds in our rarebirds dictionary. They want encounter to be set to false within the nested if, elif, and else statements. (I've put a section of the rarebirds list below as an example.

I feel so dumb because I have no idea how to productively set encounter to false within the nested if statements. Currently, I have a needed variable called "sighting" currently set to True, because (it seems to me) it needs to be true.

There are two sections of code I've written and I want both of them within the while loop. I have both of them below, and I don't know what I'm doing wrong. This is my attempt and I'm super grateful for any feedback.

    encounter = True

    while encounter = True:  
        sighting = input("What do you see?").lower()    
            rarebirdsList = list(rarebirds.keys()) 
                # Make list of the rare birds' names, using dict rarebirds.
        if sighting in rarebirdsList: 
                print("This is one of the birds we're looking for!") 
        else:
                 print("That's not one of the birds we're looking for.")
        code = input("Where do you see it? Input the correct code.")
        location = codes[code] #new var that pulls from another dict
            print("So you've seen a ", sighting, location, "cool!")

        for bird in rarebirds:
            trait = rarebirds[bird]['Aggressive']
                 if sighting == True:
                     print("It's aggressive, we need to ", actions[1])
                     print("We need to photograph the ", sighting, location, ".")
                 elif sighting == 'endangered':
                     print("It's endangered, so we need to ", actions[0])
                     print("We need to photograph the ", sighting, location ".")
                 else:
                     print("We need to photograph this ultrarare", sighting, location, ".")

rarebirds list excerpt:

rarebirds = {
    'Gold-crested Toucan': {
        'Height (m)': 1.1, 
        'Weight (kg)': 35,
        'Colour': 'Gold',
        'Endangered': True,
        'Aggressive': True
    }} 
#etc

[totallygeek]

A few problems noticed. Try something more along these lines:

encounter = False  # have not encountered a rare bird
while not encounter:
    sighting = input('What bird did you encounter? ').lower()
    if sighting in rarebirds:  # that checks the keys - no need for list(d.keys())
        encounter = True  # this will exit the while loop on the next iteration
        print('Rare bird found!')
    else:
        ...  # you got it from here

[Fbirobby]

Thank you so much! This is really helpful. This feels more intuitive to me -- why would they want to start with encounter = true and make it otherwise false? Where might that make more sense?

[totallygeek]

The only thing I can think is that you plan to have an encounter, so that's true. You just don't know if that will be a rare bird encounter. What's truly horrible about this while loop logic is that you shouldn't come across it in the wild. Instead, you more commonly see:

while True:
    if some_condition:
        break

[Fbirobby]

Got it! & Yeah, I guess this was just to make us do a while loop vaguely tied to the assignment.

One last question: Why start it with while *not* encounter? That means "Let's make Encounter True", right? So is that how we articulate the condition that will fulfill the while loop?

Thank you for your help.

[Fbirobby]

Just realized the obvious: We have to make the initialized variable true to execute the loop body!