NumPy Products
Products
To find the product of the elements in an array, use the
prod()
function.
ExampleGet your own Python Server
Find the product of the elements of this array:
import numpy as np
arr = np.array([1, 2, 3, 4])
x = np.prod(arr)
print(x)
Try it Yourself »
Returns: 24
because 1*2*3*4 = 24
Example
Find the product of the elements of two arrays:
import numpy as np
arr1 = np.array([1, 2, 3, 4])
arr2 = np.array([5,
6, 7, 8])
x = np.prod([arr1, arr2])
print(x)
Try it Yourself »
Returns: 40320
because 1*2*3*4*5*6*7*8 =
40320
Product Over an Axis
If you specify axis=1
, NumPy will return the
product of each array.
Example
Perform summation in the following array over 1st axis:
import numpy as np
arr1 = np.array([1, 2, 3, 4])
arr2 = np.array([5,
6, 7, 8])
newarr = np.prod([arr1, arr2], axis=1)
print(newarr)
Try it Yourself »
Returns: [24 1680]
Cummulative Product
Cummulative product means taking the product partially.
E.g. The partial product of [1, 2, 3, 4] is [1, 1*2, 1*2*3, 1*2*3*4] = [1, 2, 6, 24]
Perfom partial sum with the cumprod()
function.
Example
Take cummulative product of all elements for following array:
import numpy as np
arr = np.array([5,
6, 7, 8])
newarr = np.cumprod(arr)
print(newarr)
Try it Yourself »
Returns: [5 30 210 1680]
Exercise?What is this?
Test your skills by answering a few questions about the topics of this page
Consider the following code:import numpy as np
arr1 = np.array([5, 2, 3])
newarr = np.prod(arr1)
What will be the result of newarr
?