Dropping columns
Often, a DataFrame will contain columns that are not useful to your analysis. Such columns should be dropped from the DataFrame, to make it easier for you to focus on the remaining columns.
In this exercise, you'll drop the county_name column because it only contains missing values, and you'll drop the state column because all of the traffic stops took place in one state (Rhode Island). Thus, these columns can be dropped because they contain no useful information. The number of missing values in each column has been printed for you.
Este exercício faz parte do curso
Analyzing Police Activity with pandas
Instruções do exercício
- Examine the DataFrame's
.shapeto find out the number of rows and columns. - Drop both the
county_nameandstatecolumns by passing the column names to the.drop()method as a list of strings. - Examine the
.shapeagain to verify that there are now two fewer columns.
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
# Examine the shape of the DataFrame
print(ri.____)
# Drop the 'county_name' and 'state' columns
ri.____([____, ____], axis='columns', inplace=True)
# Examine the shape of the DataFrame (again)
print(____)