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Python Python Collections (Retired) Dictionaries Teacher Stats

Posted by john larson
john larson
16,594 Points

is this logic of comparing len(value) to a count = 0 variable common in python?

or is it just to make us think?

def favorite_Food(fav):
    fav_count = 0
    favorite = None
    for food, stars in fav.items():
        if len(stars) > fav_count:
            fav_count = len(stars)
            favorite = food
    return favorite.title()

1 Answer

Andreas cormack
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.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points
Andreas cormack
.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points

Hi John

Yes, its a common way of comparing the length of a list. if i has a list with fruits and wanted to know the quantity of fruits i would do it like so.See below

fruits = []
fruits.append('bananas')
fruits.append('apples')
fruits.append('mangoes')
fruits.append('grapes')

print(len(fruits)) #this would print 4
john larson
john larson
16,594 Points

Hi Andreas, Thanks for responding. I'm aware of comparing lists, but this concept was introduced because there is an undetermined number of lists to be considered. So instead of comparing list to list, the concept is comparing the length of the value of a dict, to the count variable. This determines if the current length of the iterated value is the longest value. This bypasses the need to use an empty list for comparison sake. It works, I was just wondering if it was common. It has been a definite mind bender for me :D

john larson
john larson
16,594 Points

The dict to be passed in could look something like:

favorite_foods = {
"pizza": ["*", "*", "*"],
"burgers": ["*", "*"],
"salad": ["*", "*", "*", "*", "*"]
}

favorite_food(favorite_foods )

favorite_food(favorite_foods )