Valueerror: no axis named 1 for object type series

ValueError: No axis named 1 for object type series

This error occurs when trying to perform an operation on a pandas Series using the axis parameter with the value of 1.

Series in pandas is a one-dimensional labeled array capable of holding any data type.

By default, when trying to apply functions or methods on a Series, the axis parameter is set to 0 which represents the rows (axis 0 is vertical).

However, a Series has only one dimension (no columns), so specifying axis 1 (which represents columns and is horizontal) will raise a ValueError.

Examples:

Let’s take some examples to illustrate this error.

Example 1:

import pandas as pd

# Creating a Series
data = pd.Series([1, 2, 3, 4, 5])

# Trying to apply sum along column axis
result = data.sum(axis=1)  # ValueError: No axis named 1 for object type series
        

In the above example, we are trying to compute the sum of the Series data along the column axis (axis=1). However, as mentioned earlier, a Series has only one dimension (axis 0) and doesn’t have any columns, so trying to use axis 1 will raise a ValueError.

Example 2:

import pandas as pd

# Creating a Series with column labels
data = pd.Series([1, 2, 3, 4, 5], name='numbers')

# Trying to apply mean along column axis
result = data.mean(axis=1)  # ValueError: No axis named 1 for object type series
        

In this example, we have a Series with a column label ‘numbers’. We try to calculate the mean along the column axis using axis=1. However, since a Series only has one dimension (axis 0), using axis 1 will raise a ValueError.

Solution:

To fix this error, you need to remove the axis parameter or change it to 0 when applying functions or methods on a Series. Here are the corrected versions of the examples:

Example 1 (corrected):

import pandas as pd

# Creating a Series
data = pd.Series([1, 2, 3, 4, 5])

# Computing the sum along the correct axis
result = data.sum(axis=0)
print(result)  # Output: 15
        

In this corrected example, we have removed the axis parameter when calculating the sum of the Series ‘data’. Since the Series only has one dimension (axis 0), we don’t need to specify the axis parameter.

Example 2 (corrected):

import pandas as pd

# Creating a Series with column labels
data = pd.Series([1, 2, 3, 4, 5], name='numbers')

# Computing the mean along the correct axis
result = data.mean(axis=0)
print(result)  # Output: 3.0
        

In this corrected example, we have also removed the axis parameter when calculating the mean of the Series ‘data’. Since the Series only has one dimension (axis 0), we don’t need to specify the axis parameter.