How to create matrix in Python

A Matrix is a rectangular array of data or numbers. The horizontal entries in a matrix are called as ‘rows’ while the vertical entries are called as ‘columns’. If matrix has m number of rows and n number of columns, then the order of the matrix is given as m x n.

Lets go through some methods for creating matrix in Python.

Method 1:

m = int(input("No. of rows: "))
n = int(input("No. of columns: "))

matr = []
print("Enter the entries rowwise:")

for i in range(m):          #loop for row entries
    x = []
    for j in range(n):       #loop for column entries
        x.append(int(input()))
    matr.append(x)

#printing matrix
for i in range(m):
    for j in range(n):
        print(matr[i][j], end=" ")
    print()
 

Output:

No. of rows: 2
No. of columns: 3
Enter the entries rowwise:
1
2
3
4
5
5
1 2 3
4 5 5

Method 2: Using map() function and Numpy.

NumPy is a Python library for scientific computations and multidimensional arrays. We can use NumPy to create matrix.

import numpy as np

m = int(input("No. of rows: "))
n = int(input("No. of columns: "))

matr = []
print("Enter the entries in single line separated by space:")

ele = list(map(int,input().split()))

#printing matrix
matrix = np.array(ele).reshape(m, n)
print(matrix)

Output:

No. of rows: 3
No. of columns: 4
Enter the entries in single line separated by space:
1 2 3 4 5 6 7 8 9 10 11 12
[[ 1  2  3  4]
 [ 5  6  7  8]
 [ 9 10 11 12]]