How to Fix ValueError: operands could not be broadcast together with shapes

To fix the ValueError: operands could not be broadcast together with shapes error, you can use the “numpy.reshape()” function to ensure that the shapes of the arrays are compatible.

Python raises ValueError: operands could not be broadcast together with shapes error when operating on two NumPy arrays with incompatible shapes. For example, you might try to add two arrays with different dimensions or multiply two arrays with different rows and columns.

Here’s an example of the error:

import numpy as np

x = np.array([1, 2, 3, 4])
y = np.array([[1, 2], [3, 4]])

result = x + y
print(result)

Output

ValueError: operands could not be broadcast together with shapes (3,) (2,2)

In this example, array a has shape (3,), and array b has shape (2, 2). The shapes are incompatible for broadcasting, and the addition operation raises a ValueError.

Python code that fixes the error

Use the np.reshape() function to make both arrays compatible with each other.

import numpy as np

x = np.array([1, 2, 3, 4])
y = np.array([[1, 2], [3, 4]])

x = x.reshape(2, 2)
result = x + y
print(result)

Output

[[2 4]
 [6 8]]

We reshaped the x array to have the same shape as the y array and then performed the addition operation.

Since both x and y arrays have the same shape (2, 2), the addition operation can be performed element-wise, resulting in a new (2, 2) array with the summed values.

That’s it.