Data Science with Python Certification Introduction to Python for Data Science 3

Question 1

Which NumPy function is used to create an array of evenly spaced values over a specified interval?

Accepted Answer

np.linspace()

Answer

`np.linspace(start, stop, num)` returns `num` evenly spaced values between `start` and `stop` inclusive.

Question 2

What does the `shape` attribute of a NumPy array return?

Accepted Answer

A tuple of the array's dimensions

Answer

The `shape` attribute returns a tuple representing the size of each dimension of the array.

Question 3

Which pandas method is used to read a CSV file into a DataFrame?

Accepted Answer

pd.read_csv()

Answer

`pd.read_csv()` is the standard pandas function for reading comma-separated value files into a DataFrame.

Question 4

In a pandas DataFrame, what does `df.head(3)` return?

Accepted Answer

The first 3 rows

Answer

`df.head(n)` returns the first `n` rows of the DataFrame, defaulting to 5 if no argument is passed.

Question 5

What is broadcasting in NumPy?

Accepted Answer

Performing element-wise operations on arrays of different shapes

Answer

Broadcasting allows NumPy to perform arithmetic operations on arrays of different shapes by virtually expanding the smaller array.

Data Science with Python Certification Practice Test