Kenneth says that "like dictionaries", we can use the update function. What does he mean by that?

Question

I watched the dictionaries video but i don't remember using any update function on dictionaries. what does Kenneth mean by that? How can we use the update function on a dictionary similar to the one we use on sets? thanks

Answer 1 · 2019-04-05T14:15:51Z

April 5, 2019 2:15pm

I think he means that you can use the update() method on sets and dictionaries.

Of course sets will add unique values while dictionaries will update existing keys.

Here's some code to play with and hopefully clear things up a bit:

list1 = [1, 2, 3, 1, 2, 3]
list2 = [5, 6, 7, 5, 6, 7, 'zzz']

set1 = set(list1)
set2 = set(list2)
set3 = set(list1)
set4 = set(list2)

print('Set1 is ---> {}'.format(set1))
print('Set2 is ---> {}'.format(set2))
print('Set3 is ---> {}'.format(set3))
print('Set4 is ---> {}'.format(set4))

set2.update(set1)

print('Updated Set2 is ---> {}'.format(set2))

dict1 = {x: y for x, y in enumerate(set3)}
dict2 = {x: y for x, y in enumerate(set4)}

for k, v in dict1.items():
    print('Before Update Key is {} and value is {}'.format(k, v))

dict1.update(dict2)

for k, v in dict1.items():
    print('After Update Key is {} and value is {}'.format(k, v))

#outputs
Set1 is ---> {1, 2, 3}
Set2 is ---> {'zzz', 5, 6, 7}
Set3 is ---> {1, 2, 3}
Set4 is ---> {'zzz', 5, 6, 7}
Updated Set2 is ---> {1, 2, 3, 5, 6, 7, 'zzz'}
Before Update Key is 0 and value is 1
Before Update Key is 1 and value is 2
Before Update Key is 2 and value is 3
After Update Key is 0 and value is zzz
After Update Key is 1 and value is 5
After Update Key is 2 and value is 6
After Update Key is 3 and value is 7

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Siddesh Gannu

Siddesh Gannu

Kenneth says that "like dictionaries", we can use the update function. What does he mean by that?

1 Answer

Dave StSomeWhere

Dave StSomeWhere