HackerRank Linear Algebra problem solution in Python

HackerRank Linear Algebra problem solution in Python – In this Linear Algebra problem, you are given a square matrix A with dimensions N X N. Your task is to find the determinant. Note: Round the answer to 2 places after the decimal.

The NumPy module also comes with a number of built-in routines for linear algebra calculations. These can be found in the sub-module linalg.

linalg.det

The linalg.det tool computes the determinant of an array.

print numpy.linalg.det([[1 , 2], [2, 1]])       #Output : -3.0

linalg.eig

The linalg.eig computes the eigenvalues and right eigenvectors of a square array.

vals, vecs = numpy.linalg.eig([[1 , 2], [2, 1]])
print vals                                      #Output : [ 3. -1.]
print vecs                                      #Output : [[ 0.70710678 -0.70710678]
                                                #          [ 0.70710678  0.70710678]]

linalg.inv

The linalg.inv tool computes the (multiplicative) inverse of a matrix.

print numpy.linalg.inv([[1 , 2], [2, 1]])       #Output : [[-0.33333333  0.66666667]
                                                #          [ 0.66666667 -0.33333333]]

HackerRank Linear Algebra problem solution in Python 2.

import numpy
import sys

lineNum = 0
matrix = []
for line in sys.stdin:
    if lineNum==0:
        m_size = int(line)
    else:
        matrix.append(map(float,line.split()))
    lineNum+=1

print numpy.linalg.det(matrix)

Linear Algebra solution in Python 3.

import numpy
n=int(input())
a=numpy.array([input().split() for _ in range(n)],float)
numpy.set_printoptions(legacy='1.13') #important
print(numpy.linalg.det(a))

Problem solution in pypy programming.

# Enter your code here. Read input from STDIN. Print output to STDOUT
import numpy
n = int(raw_input())
arr = [map(float, raw_input().split()) for _ in range(n)]
print numpy.linalg.det(arr)

Problem solution in pypy3 programming.

# Enter your code here. Read input from STDIN. Print output to STDOUT
import numpy

n = int(input().strip())
array = []
for _ in range(n):
    array.append([float(x) for x in input().strip().split(' ')])
print(numpy.linalg.det(array))