Python Sets - Adding to a Set
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Let's say the Burger King wasn't having things his way and decided to quit and join the McDonald's gang. After a rough initiation (he gunned down Jack from Jack in the Box), he is allowed in. Since Ronald is a demanding boss, we want to add him to our Set. We could do so this way:
#!/usr/local/bin/python
mcdonaldgang = Set (['Grimace', 'Hamburglar', 'Mayor Mccheese'])
print mcdonaldgang
mcdonaldgang.add('Burger King')
print mcdonaldgang
The above would first print out our original set, then add the Burger King to it, and print it once more:
Hamburglar, Grimace, Mayor Mccheese
Hamburglar Burger King Grimace Mayor Mccheese
Let's say not only the Burger King, but Wendy herself wanted to join the gang. To add more than one new element at the same time, we would use the Update function:
!/usr/local/bin/python
mcdonaldgang = Set (['Grimace', 'Hamburglar', 'Mayor Mccheese'])
print mcdonaldgang
mcdonaldgang.update(['Burger King', 'Wendy'])
print mcdonaldgang
Again, we set the initial values for the set mcdonaldgang, printed those values, then used the update function to add two more elements to the set. The resulting print out would be:
Grimace Mayor Mccheese Hamburglar
Hamburglar Mayor Mccheese Grimace Wendy Burger King
Again note that Sets do not allow for duplicate values. Let's say the Fry Guys all wanted to join the McDonald's Gang. Let's add them to our database and see what happens.
/usr/local/bin/python
mcdonaldgang = Set (['Grimace', 'Hamburglar', 'Mayor Mccheese', 'Burger King', 'Wendy'])
print mcdonaldgang
mcdonaldgang.update(['Fry Guy', 'Fry Guy', 'Fry Guy'])
print mcdonaldgang
This will result in the print out:
Grimace Mayor Mccheese Hamburglar Burger King Wendy
Fry Guy Grimace Mayor Mccheese Hamburglar Burger King Wendy
As you can see it only adds the one Fry Guy. Too bad for the rest of them. That's what you get for all having the same name.
Next: Copying Sets and Testing for Membership >>
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