eigh Interface

public interface eigh

This interface overloads the eigh interface from stdlib_linalg to compute the eigenvalues and eigenvectors of a matrix whose type is SymTridiagonal.

Syntax

   call eigh(A, lambda [, vectors])

Arguments

  • A : Matrix of SymTridiagonal. It is an intent(in) argument.

  • lambda : Rank-1 real array returning the eigenvalues of A in increasing order. It is an intent(out) argument.

  • vectors (optional) : Rank-2 array of the same kind as A returning the eigenvectors of A. It is an intent(out) argument.


Subroutines

private module subroutine eigh_rdp(A, lambda, vectors)

Compute the eigenvalues and eigenvectors of a SymTridiagonal matrix.

Arguments

Type IntentOptional Attributes Name
type(SymTridiagonal), intent(in) :: A

Input matrix.
real(kind=dp), intent(out), allocatable :: lambda(:)

Eigenvalues.
real(kind=dp), intent(out), optional, allocatable, target :: vectors(:,:)

Eigenvectors.