Checking if string contains values of nested lists - python

You should try to debug these kinds of problems yourself by breaking down what happens at each step. Printing the variables at each stage or playing around with a shell or debugger such as pdb are very helpful. In this case:

>>> Bill_Gates = ["bill gates","1955", "Co-founder of Microsoft"]
>>> Steve_Jobs = ["steve jobs","1955", "Co-Founder of Apple"]
>>> Albert_Einstein = ["albert einstein","1879", "Phycisist"]
>>> 
>>> PEOPLE = [Bill_Gates, Steve_Jobs, Albert_Einstein]
>>> things = [j for i in PEOPLE for j in i]
>>> things
['bill gates', '1955', 'Co-founder of Microsoft', 'steve jobs', '1955', 'Co-Founder of Apple', 'albert einstein', '1879', 'Phycisist']
>>> 'steve jobs' in things
True
>>> 'when was steve jobs born' in things
False

So the if userInput in [j for i in PEOPLE for j in i] fails because the right hand side is just a list of strings and Python isn't magic.

Your code is almost there anyway, as it works without the initial check. So this works:

for person in PEOPLE:
    if person[0] in userInput and "when was" in userInput and "born" in userInput:
        print(person[0] + " was born in " + person[1])

Note that a direct for loop works in this situation; there is no need to use range and index manually. Using the and operator is also cleaner than nested if statements.

This is plenty efficient as is unless PEOPLE has some tens of millions of elements. If you get to that stage you can look into search engine indexing techniques.

'when was steve jobs born' isn't in that list you made, whatever it is; since the outer if fails, nothing inside it gets executed.

What about making a Person class? It's simple, readable and easy to manage.

For example, I've written a Person class with a get_role method. Write your own get_name() and get_year_of_birth method.

class Person:
    def __init__(self, name, year_of_birth, role):
        self.name = name
        self.year_of_birth = year_of_birth
        self.role = role

    def get_role(self):
        return self.role

Bill_Gates = Person("bill gates","1955", "Co-founder of Microsoft")
Steve_Jobs = Person("steve jobs","1955", "Co-Founder of Apple")
Albert_Einstein = Person("albert einstein","1879", "Phycisist")


person_list= [Bill_Gates,Steve_Jobs,Albert_Einstein]


for person in person_list:
    print person.get_role()

Output:

Co-founder of Microsoft
Co-Founder of Apple
Phycisist