orthonormal matrix

[LA] Orthogonal matrix (직교행렬)

Orthogonal MatrixMatrix의 row vector (and column vector)들이자기자신을 제외한 나머지 row vector (and column vector)들과 orthonormal인 square matrix.$$A^{-1}=A^T \\ A^TA = I \\ \mathbf{a}_i^T \mathbf{a}_j = \mathbf{a}_i \cdot \mathbf{a}_j = 0, \quad \text{ where } i\ne j \\ \mathbf{a}_i^T \mathbf{a}_j = \mathbf{a}_i \cdot \mathbf{a}_j = 0, \quad \text{ where } i = j$$엄격히 애기해서 orthogonal matrix는 $A^{-1}=A^T$인 경우로 ..