Inverse Matrix

  import numpy as np

2x2 example

  A = np.array([[7, 4], [5, 7]])
  A_inv = np.linalg.inv(A)
  print(A_inv)

3x3 example

  B = np.array([[1, 2, 3], [0, 1, 4], [5, 6, 0]])
  B_inv = np.linalg.inv(B)
  print(B_inv)

properties

A^-1 * A = A * A^-1 = I
  I1 = np.dot(A, A_inv)
  print(I1)
  I2 = np.dot(A_inv, A)
  print(I2)
(AB)^−1=B^−1A^−1
  A = np.array([[2, 1], [5, 3]])
  B = np.array([[1, 2], [3, 4]])
  A_inv = np.linalg.inv(A)
  B_inv = np.linalg.inv(B)
  AB = np.dot(A, B)
  AB_inv = np.linalg.inv(AB)
  result = np.dot(B_inv, A_inv)
  print(AB_inv)
  print(result)
(A^T)^−1=(A^−1)^T
  A_T = np.transpose(A)
  A_T_inv = np.linalg.inv(A_T)
  A_inv_T = np.transpose(A_inv)
  print(A_T_inv)
  print(A_inv_T)
(kA)^−1=(1/k)(​A^−1)
  k = 2
  kA = k * A
  kA_inv = np.linalg.inv(kA)
  scaled_result = (1 / k) * A_inv
  print(kA_inv)
  print(scaled_result)
(A^−1)^−1=A
  A_double_inv = np.linalg.inv(A_inv)
  print(A_double_inv)

Ryan is a Data Scientist at a fintech company, where he focuses on fraud prevention in underwriting and risk. Before that, he worked as a Data Analyst at a tax software company. He holds a degree in Electrical Engineering from UCF.

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