I have an experience in java and c++ for 7 years now. I recently started learning python. Can someone please help me on how to read the input for the matrix and display the same in matrix format. This is the code I wrote:
import sys
# no of rows are equal to the number of columns.
n = int(input("Enter the number of rows in a matrix"))
a = [[0 for x in range (n)] for y in range(n)]
for i in range (n):
for j in range(n):
a[i][j]=int(input())
print (a[i][j])
print("\n")
If you use pandas, and make a dataframe... if you enter 4 for the number of rows, and the numbers 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16... the script below
import pandas as pd
n = int(input("Enter the number of rows in a matrix: "))
a = [[0] * n for i in range(n)]
col_names = []
row_names = []
for i in range(n):
col_names.append('col ' + str(i+1))
row_names.append('row ' + str(i+1))
for j in range(n):
a[i][j] = int(input())
print(pd.DataFrame(a,columns = col_names, index = row_names))
...will produce the following output.
col 1 col 2 col 3 col 4
row 1 1 2 3 4
row 2 5 6 7 8
row 3 9 10 11 12
row 4 13 14 15 16
Another option... using numpy... and the same values from the first option...
import numpy as np
n = int(input("Enter the number of rows in a matrix: "))
a = [[0] * n for i in range(n)]
for i in range(n):
for j in range(n):
a[i][j] = int(input())
print(np.matrix(a))
...would produce
[[ 1 2 3 4]
[ 5 6 7 8]
[ 9 10 11 12]
[13 14 15 16]]
#program to print matirx by row and column input
a,b = map(int,input("Enter row and column of matrix separated by a space ").split())
# empty list for matrix
m=[]
# taking matrix input
for i in range(1,a+1):
l=[]
for j in range(1,b+1):
n=int(input(f"Enter a[{i}][{j}] element "))
l.append(n)
m.append(l)
#printing in matrix form
for i in range(a):
for j in range(b):
if(j==b-1):
print(m[i][j], end="")
else:
print(m[i][j], end=" ")
if i!=a-1:
print()
This example from a program I use for calculating bigger matrices:
matrix = []
rows = int(input("Num rows: "))
cols = int(input("Num columns: "))
for r in range(rows):
row = []
for c in range(cols):
row.append(int(input("M1-> R: {} C: {}\n>>>".format(r+1, c+1))))
matrix.append(row)
print(matrix)
This will work for non-square matrices as well. I also use Sympy for doing matrix calculations, but that's besides the point:)
print"ENter r and c"
r = int(input("Enter the number of rows in a matrix"))
c = int(input("Enter the number of columns in a matrix"))
a = [[int(input()) for x in range (c)] for y in range(r)]
import numpy as np
#Taking the number of rows and columns from user
n=int(input("Enter the number of Rows\n"))
m=int(input("Enter the number of Columns\n"))
"""
You can either use this loop method for below list comprehension;
a=[]
for i in range(n):
a.append([0] * m )
"""
#Creating a Empty matrix as as per the instruction of user;
a = [ [0] * m for i in range(n) ]
#Taking the element for a matrix from user;
for i in range (n):
for j in range(m):
print("Enter Element No:",i,j)
a[i][j] = int(input())
print(np.matrix(a))
r = int(input("Enter Number of Rows : "))
c = int(input("Enter Number of Cols : "))
a = []
for i in range(r):
b = []
for j in range(c):
j = int(input("Enter Number in pocket [" + str(i) + "][" + str(j) + "]"))
b.append(j)
a.append(b)
print("Matrix is ......")
for i in range(r):
for j in range(c):
print(a[i][j], end=" ")
print()
r = int(input("Enter the number of rows in a matrix"))
c = int(input("Enter the number of columns in a matrix"))
a = [list(map(int,input().split())) for _ in range(r)]
for i in a:
print(*i)
list = []
for i in range(3):
list.append([])
for j in range(3):
list[i].append(2)
for i in range(3):
for j in range(3):
print(list[i][j],end=" ")
print()
