Numpy.prod() in Python

numpy.prod() is used to calculate the product of array elements. It can multiply all elements of an array or multiply elements along a specific axis in multi-dimensional arrays. It is commonly used in numerical computing when we need the multiplication result of multiple values stored in a NumPy array.

Example: This example multiplies all elements of a NumPy array using np.prod().

24

Explanation: np.prod(arr) multiplies all elements of arr: 1 × 2 × 3 × 4 = 24.

Syntax

numpy.prod(a, axis=None, dtype=None, out=None, keepdims=False)

Parameters:

• a: Input array whose elements are multiplied.
• axis: Axis along which the product is calculated. By default, product of all elements is returned.
• dtype: Data type of the returned result.
• out: Alternative output array to store the result.
• keepdims: If True, reduced axes are kept as dimensions with size 1.

Examples

Example 1: This example finds the product of all elements in a 1D array using np.prod().

24

Explanation: np.prod(arr) multiplies all array elements: 2 × 3 × 4 = 24.

Example 2: This example calculates the product of elements row-wise in a 2D array using axis=1.

[ 2 12]

Explanation: axis=1 calculates the product across each row:

• First row: 1 × 2 = 2
• Second row: 3 × 4 = 12

Example 3: This example shows the result when np.prod() is applied to an empty array.

1.0

Explanation: For an empty array, np.prod() returns 1.0, which is the neutral value for multiplication.