Python Data Science Tool Box -1

Question 1

Good to Remember : Tuples

Answer 1

Note that the return statement return x, y has the same result as return (x, y): the former actually packs x and y into a tuple under the hood!

Question 2

How would you write a lambda function add_bangs that adds three exclamation points ‘!!!’ to the end of a string a?

How would you call add_bangs with the argument ‘hello’?

Answer 2

The lambda function definition is:

add_bangs = (lambda a: a + ‘!!!’),

and the function call is: add_bangs(‘hello’).

Question 3

nums = [2, 4, 6, 8, 10]

result = map(lambda a: a ** 2, nums)

What does this piece of lambda code do?

Answer 3

You can see here that a lambda function, which raises a value a to the power of 2, is passed to map() alongside a list of numbers, nums. The map object that results from the call to map() is stored in result.

Question 4

Whar does the map() do?

Answer 4

map() applies a function over an object, such as a list.

Question 5

What does the filter () do?

Answer 5

The function filter() offers a way to filter out elements from a list that don’t satisfy certain criteria.

Question 6

What are the 2 ways of raising an exception?

Answer 6

try : except:

and using raise