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The NumPy library is very helpful for solving linear systems in python. For how to install NumPy look here

Importing NumPy

All the code-snippets below has numpy importet as np. To learn how see the installation of NumPy

Matrixes in Python

Creating a matrix
a = np.array([[1,2],[3,4]])

In Python rows and columns start at 0. For example index the data at first row second column : 

Indexing matrix
b = a[0,1]


Linear algebra using NumPy

NumPy has several useful functions for linear algebra built-in. For full list look check the NumPy documentation.


Solve()
np.linalg.solve(a,b) #where a and b is matrixs


#returns a array with solutions to the system


Eigenvalues and eigenvectors
np.linalg.eig(a) # where a is a square matrix


#returns two arrays [v,w]
#v containing the eigenvalues of a
#w containing the eigenvectors of a


Determinant
np.linalg.det(a) # where a is a square matrix


#returns the determinant of the matrix a
Finding the inverse
np.linalg.inv(a) # where a is the matrix to be inverted


#Returns the inverse matrix of a

Example

Solving set of equations
import numpy as np

# Solving following system of linear equation
# 5a + 2b = 35
# 1a + 4b = 49

a = np.array([[5, 2],[1,4]]) # Lefthand-side of the equation
b = np.array([35, 94]) #Righthand-side

print(np.linalg.solve(a,b)) #Printing the solution


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