Lambda Functions

Which of the following built-in functions can be used to find the length of a list of strings using a lambda function?

A:

len()

B:

map()

C:

reduce()

D:

filter()

Answer: A

The len() function can be used with a lambda function to find the length of a list of strings.

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What is the output of the following code?

numbers = [1, 2, 3, 4, 5]
result = list(filter(lambda x: x % 2 == 0, numbers))
print(result)

A:

[2, 4]

B:

[1, 3, 5]

C:

[1, 2, 3, 4, 5]

D:

[1, 4]

Answer: A

The filter() function with the lambda filters even numbers from the list.

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What does the following lambda function accomplish?

lambda x: x.split()[0]

A:

Splits a string into a list.

B:

Extracts the first word from a string.

C:

Concatenates two strings.

D:

Reverses a string.

Answer: B

The lambda function extracts the first word from a string using the split() method.

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How is a lambda function different from a regular function?

A:

Lambda functions can have multiple expressions.

B:

Regular functions are always more memory-efficient.

C:

Lambda functions can have named parameters.

D:

Regular functions cannot be used as arguments in higher-order functions.

Answer: A

Lambda functions are limited to a single expression, making them concise for short tasks.

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What is the purpose of the functools.partial() function in relation to lambda functions?

A:

To create a partial application of a lambda function.

B:

To create a filter object based on the lambda function's condition.

C:

To sort the elements of an iterable using the lambda function.

D:

To apply the lambda function to each element of an iterable.

Answer: A

functools.partial() is used to create a partial application of a function, including lambda functions, by fixing certain arguments.

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Questions for: Lambda Functions