upgtr Interface

public interface upgtr

UPGTR generates a complex unitary matrix Q which is defined as the product of n-1 elementary reflectors H(i) of order n, as returned by CHPTRD using packed storage: if UPLO = 'U', Q = H(n-1) . . . H(2) H(1), if UPLO = 'L', Q = H(1) H(2) . . . H(n-1).


Subroutines

public pure subroutine cupgtr(uplo, n, ap, tau, q, ldq, work, info)

Arguments

Type IntentOptional Attributes Name
character(len=1), intent(in) :: uplo
integer(kind=ilp), intent(in) :: n
complex(kind=sp), intent(in) :: ap(*)
complex(kind=sp), intent(in) :: tau(*)
complex(kind=sp), intent(out) :: q(ldq,*)
integer(kind=ilp), intent(in) :: ldq
complex(kind=sp), intent(out) :: work(*)
integer(kind=ilp), intent(out) :: info

public pure subroutine zupgtr(uplo, n, ap, tau, q, ldq, work, info)

Arguments

Type IntentOptional Attributes Name
character(len=1), intent(in) :: uplo
integer(kind=ilp), intent(in) :: n
complex(kind=dp), intent(in) :: ap(*)
complex(kind=dp), intent(in) :: tau(*)
complex(kind=dp), intent(out) :: q(ldq,*)
integer(kind=ilp), intent(in) :: ldq
complex(kind=dp), intent(out) :: work(*)
integer(kind=ilp), intent(out) :: info

Module Procedures

public interface stdlib_cupgtr()

Arguments

None

public interface stdlib_zupgtr()

Arguments

None