How to Solve Python AttributeError: ‘numpy.float64’ object has no attribute ‘isna’

This error occurs if you try to call isna() on a numpy.float64 object. If you want to evaluate whether a value is NaN or not in a Series or DataFrame object, you use can use the Series.isna() and DataFrame.isna() methods respectively. For example,

import pandas as pd
import numpy as np

ser = pd.Series([np.nan, np.nan, 3, 4 , 7])

ser_2 = np.where(ser.isna()==False, ser, 0) 

You can also use Series.isnull() and DataFrame.isnull() which are aliases for the isna() methods.

This tutorial will go through the error in detail and how to solve it with code examples.

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How to Solve AttributeError: ‘numpy.float64’ object has no attribute ‘isna’

AttributeError occurs in a Python program when we try to access an attribute (method or property) that does not exist for a particular object. The part “‘numpy.float64’ object has no attribute ‘isna’” tells us that the numpy.float64 object we are handling does not have the isna attribute. isna() is a pandas DataFrame and Series method which returns a boolean object the same size as the original, indicating which values are NA.

Example

Let’s look at an example to reproduce the error.

# Import Pandas and NumPy libraries

import pandas as pd
import numpy as np

# Create Series object

ser = pd.Series([np.nan, np.nan, 3, 4 , 7])

# For loop over elements in Series

for ele in ser:

# Check if element is NaN

    if ele.isna():

# Replace NaN with 0

        ser = ser.replace(ele,0)

# Print 0

print(ser)

Let’s run the code to see what happens:

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
Input In [19], in <cell line: 6>()
      4 ser = pd.Series([np.nan, np.nan, 3, 4 , 7])
      6 for ele in ser:
----> 7     if ele.isna():
      8         ser = ser.replace(ele,0)
     10 print(ser)

AttributeError: 'float' object has no attribute 'isna'

The error occurs because we are trying to call the isna() method on the elements in the Series object, which are numpy.float64.

Solution

We can solve the error by using the Series method isna(). Let’s look at the revised code:

# Import Pandas and NumPy libraries

import pandas as pd
import numpy as np

# Create Series object

ser = pd.Series([np.nan, np.nan, 3, 4 , 7])

# Create numpy array using where function

arr = np.where(ser.isna()==False, ser, 0) 

# Convert array to Series

ser_2 = pd.Series(arr)

# Print Series object

print(ser_2)

# Confirm type of object

print(type(ser_2))

The numpy where method returns the element from the original series if the condition ser.isna()==False otherwise it returns 0. Let’s run the code to get the result:

0    0.0
1    0.0
2    3.0
3    4.0
4    7.0
dtype: float64

<class 'pandas.core.series.Series'>

We successfully retrieved a Series object derived from the original, where the NaN values are replaced by 0 and the non NaN are left unchanged.

Summary

Congratulations on reading to the end of this tutorial!

For further reading on AttributeErrors, go to the article;

How to Solve Python AttributeError: ‘Series’ object has no attribute ‘lower’

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Have fun and happy researching!