Let’s say we have a dataset. We want to know the total number of non-null values in each column of the dataset. We can use the count() function in the pandas Python library to find out the same.

import pandas

df = pandas.read_csv("iris.csv")
print(df.head())

print("The total number of non-null values in each column: \n", df.count())

Here, we are first reading the iris dataset from a CSV file and creating the DataFrame df. After that, we are calling the DataFrame.count() function to find out the total number of non-null values in each column of the DataFrame.

The output of the above program will be:

   sepal_length  sepal_width  petal_length  petal_width species
0           5.1          3.5           1.4          0.2  setosa
1           4.9          3.0           1.4          0.2  setosa
2           4.7          3.2           1.3          0.2  setosa
3           4.6          3.1           1.5          0.2  setosa
4           5.0          3.6           1.4          0.2  setosa
The total number of non-null values in each column: 
sepal_length    150
sepal_width     150
petal_length    150
petal_width     150
species         150
dtype: int64