Calculate Missing Percents
Automation is the future of data science. Learning to automate some of your data preparation pays dividends. In this exercise, we will automate dropping columns if they are missing data beyond a specific threshold.
Este exercício faz parte do curso
Feature Engineering with PySpark
Instruções do exercício
- Define a function
column_dropper()
that takes the parametersdf
a dataframe andthreshold
a float between 0 and 1. - Calculate the percentage of values that are missing using
where()
,isNull()
andcount()
- Check to see if the percentage of missing is higher than the threshold, if so, drop the column using
drop()
- Run
column_dropper()
ondf
with the threshold set to .6
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
def column_dropper(df, threshold):
# Takes a dataframe and threshold for missing values. Returns a dataframe.
total_records = df.____()
for col in df.columns:
# Calculate the percentage of missing values
missing = df.____(df[col].____()).____()
missing_percent = ____ / ____
# Drop column if percent of missing is more than threshold
if ____ > ____:
df = df.____(col)
return df
# Drop columns that are more than 60% missing
df = ____(____, ____)