Eigenvalues and Eigenvectors in MATLAB
Eigenvalues and Eigenvectors are properties of a square matrix.
Let is an N*N matrix, X be a vector of size N*1 and be a scalar.
Then the values X, satisfying the equation are eigenvectors and eigenvalues of matrix A respectively.
- A matrix of size N*N possess N eigenvalues
- Every eigenvalue corresponds to an eigenvector.
Matlab allows the users to find eigenvalues and eigenvectors of matrix using eig() method. Different syntaxes of eig() method are:
- e = eig(A)
- [V,D] = eig(A)
- [V,D,W] = eig(A)
- e = eig(A,B)
Let us discuss the above syntaxes in detail:
e = eig(A)
- It returns the vector of eigenvalues of square matrix A.
[V,D] = eig(A)
- It returns the diagonal matrix D having diagonals as eigenvalues.
- It also returns the matrix of right vectors as V.
- Normal eigenvectors are termed as right eigenvectors.
- V is a collection of N eigenvectors of each N*1 size(A is N*N size) that satisfies A*V = V*D
[V,D,W] = eig(A)
- Along with the diagonal matrix of eigenvalues D and right eigenvectors V, it also returns the left eigenvectors of matrix A.
- A left eigenvector u is a 1*N matrix that satisfies the equation u*A = k*u, where k is a left eigenvalue of matrix A.
- W is the collection of N left eigenvectors of A that satisfies W’*A = D*W’.
e = eig(A,B)
- It returns the generalized eigenvalues of two square matrices A and B of the same size.
- A generalized eigenvalue λ and a corresponding eigenvector v satisfy Av=λBv.
Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready. To complete your preparation from learning a language to DS Algo and many more, please refer Complete Interview Preparation Course.