unhr_col Interface

public interface unhr_col

UNHR_COL takes an M-by-N complex matrix Q_in with orthonormal columns as input, stored in A, and performs Householder Reconstruction (HR), i.e. reconstructs Householder vectors V(i) implicitly representing another M-by-N matrix Q_out, with the property that Q_in = Q_out*S, where S is an N-by-N diagonal matrix with diagonal entries equal to +1 or -1. The Householder vectors (columns V(i) of V) are stored in A on output, and the diagonal entries of S are stored in D. Block reflectors are also returned in T (same output format as CGEQRT).


Subroutines

public pure subroutine cunhr_col(m, n, nb, a, lda, t, ldt, d, info)

Arguments

Type IntentOptional Attributes Name
integer(kind=ilp), intent(in) :: m
integer(kind=ilp), intent(in) :: n
integer(kind=ilp), intent(in) :: nb
complex(kind=sp), intent(inout) :: a(lda,*)
integer(kind=ilp), intent(in) :: lda
complex(kind=sp), intent(out) :: t(ldt,*)
integer(kind=ilp), intent(in) :: ldt
complex(kind=sp), intent(out) :: d(*)
integer(kind=ilp), intent(out) :: info

public pure subroutine zunhr_col(m, n, nb, a, lda, t, ldt, d, info)

Arguments

Type IntentOptional Attributes Name
integer(kind=ilp), intent(in) :: m
integer(kind=ilp), intent(in) :: n
integer(kind=ilp), intent(in) :: nb
complex(kind=dp), intent(inout) :: a(lda,*)
integer(kind=ilp), intent(in) :: lda
complex(kind=dp), intent(out) :: t(ldt,*)
integer(kind=ilp), intent(in) :: ldt
complex(kind=dp), intent(out) :: d(*)
integer(kind=ilp), intent(out) :: info

Module Procedures

public interface stdlib_cunhr_col()

Arguments

None

public interface stdlib_zunhr_col()

Arguments

None