'numpy.ndarray' object has no attribute 'to_csv'

The error message suggests that you are trying to call the `to_csv` method on a NumPy array object, which does not have such a method. The `to_csv` method is a pandas method used to write a DataFrame to a CSV file.

To fix the error, you need to convert your NumPy array to a pandas DataFrame first, and then call the `to_csv` method on the DataFrame object. Here is an example code snippet:

import pandas as pd
import numpy as np

# create a NumPy array
arr = np.array([[1, 2], [3, 4]])

# convert the NumPy array to a pandas DataFrame
df = pd.DataFrame(arr)

# write the DataFrame to a CSV file
df.to_csv("output.csv", index=False)

In this example, we first create a NumPy array `arr`, and then convert it to a pandas DataFrame `df`. Finally, we use the `to_csv` method to write the DataFrame to a CSV file named "output.csv". Note that we set `index=False` to exclude the index column in the output file.