Solve the eigenvalue problem of H(N,N) real symmetric matrix using dsyevx - matrix: real, H(N,N) - eigenvalues: real, E(num) - eigenvectors: real, Z(N,num) - num: number of eigenvectors and eigenvalues with lowest eigenvalues - epsilon: (optional) absolute tolerance Eigenvalues are stored in E(N)
| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| real(kind=long), | intent(inout) | :: | h(:,:) | |||
| real(kind=long), | intent(out) | :: | e(num) | |||
| real(kind=long), | intent(out) | :: | z(size(h,1),num) | |||
| integer, | intent(in) | :: | num | |||
| real(kind=long), | intent(in), | optional | :: | epsilon | ||
| logical, | intent(in), | optional | :: | yes_verbose |