Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Matrix product of a 1D (first argument) and a 2D array (second argument) in Numpy
To find the matrix product of a 2D and a 1D array, use the numpy.matmul() method in Python Numpy. If the first argument is 1-D, it is promoted to a matrix by prepending a 1 to its dimensions. After matrix multiplication the prepended 1 is removed.
Returns the matrix product of the inputs. This is a scalar only when both x1, x2 are 1-d vectors. The out is a location into which the result is stored. If provided, it must have a shape that matches the signature (n,k),(k,m)->(n,m). If not provided or None, a freshly-allocated array is returned.
Steps
At first, import the required library −
import numpy as np
Create a 1D and a 2D array −
arr1 = np.array([25, 35]) arr2 = np.array([[5, 7], [10, 15]])
Display the arrays −
print("Array 1 (Two Dimensional)...
", arr1)
print("
Array 2 (One Dimensional)...
", arr2)Get the type of the arrays −
print("
Our Array 1 type...
", arr1.dtype)
print("
Our Array 2 type...
", arr2.dtype)Get the dimensions of the Arrays −
print("
Our Array 1 Dimensions...
",arr1.ndim)
print("
Our Array 2 Dimensions...
",arr2.ndim)Get the shape of the Arrays −
print("
Our Array 1 Shape...
",arr1.shape)
print("
Our Array 2 Shape...
",arr2.shape)To find the matrix product of a 2D and a 1D array, use the numpy.matmul() method in Python Numpy. If the first argument is 1-D, it is promoted to a matrix by prepending a 1 to its dimensions. After matrix multiplication the prepended 1 is removed −
print("
Result (matrix product)...
",np.matmul(arr1, arr2))
Example
import numpy as np
# Create a 1D and a 2D array
arr1 = np.array([25, 35])
arr2 = np.array([[5, 7], [10, 15]])
# Display the arrays
print("Array 1 (Two Dimensional)...
", arr1)
print("
Array 2 (One Dimensional)...
", arr2)
# Get the type of the arrays
print("
Our Array 1 type...
", arr1.dtype)
print("
Our Array 2 type...
", arr2.dtype)
# Get the dimensions of the Arrays
print("
Our Array 1 Dimensions...
",arr1.ndim)
print("
Our Array 2 Dimensions...
",arr2.ndim)
# Get the shape of the Arrays
print("
Our Array 1 Shape...
",arr1.shape)
print("
Our Array 2 Shape...
",arr2.shape)
# To find the matrix product of a 2D and a 1D array, use the numpy.matmul() method in Python Numpy
# If the first argument is 1-D, it is promoted to a matrix by prepending a 1 to its dimensions.
# After matrix multiplication the prepended 1 is removed.
print("
Result (matrix product)...
",np.matmul(arr1, arr2))Output
Array 1 (Two Dimensional)... [25 35] Array 2 (One Dimensional)... [[ 5 7] [10 15]] Our Array 1 type... int64 Our Array 2 type... int64 Our Array 1 Dimensions... 1 Our Array 2 Dimensions... 2 Our Array 1 Shape... (2,) Our Array 2 Shape... (2, 2) Result (matrix product)... [475 700]
194 Views
