dtrttp()

subroutine dtrttp	(	character	uplo,
		integer	n,
		double precision, dimension( lda, * )	a,
		integer	lda,
		double precision, dimension( * )	ap,
		integer	info )

DTRTTP copies a triangular matrix from the standard full format (TR) to the standard packed format (TP).

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Purpose:

!>
!> DTRTTP copies a triangular matrix A from full format (TR) to standard
!> packed format (TP).
!> 

Parameters

[in]	UPLO	!> UPLO is CHARACTER*1 !> = 'U': A is upper triangular. !> = 'L': A is lower triangular. !>
[in]	N	!> N is INTEGER !> The order of the matrices AP and A. N >= 0. !>
[in]	A	!> A is DOUBLE PRECISION array, dimension (LDA,N) !> On exit, the triangular matrix A. If UPLO = 'U', the leading !> N-by-N upper triangular part of A contains the upper !> triangular part of the matrix A, and the strictly lower !> triangular part of A is not referenced. If UPLO = 'L', the !> leading N-by-N lower triangular part of A contains the lower !> triangular part of the matrix A, and the strictly upper !> triangular part of A is not referenced. !>
[in]	LDA	!> LDA is INTEGER !> The leading dimension of the array A. LDA >= max(1,N). !>
[out]	AP	!> AP is DOUBLE PRECISION array, dimension (N*(N+1)/2) !> On exit, the upper or lower triangular matrix A, packed !> columnwise in a linear array. The j-th column of A is stored !> in the array AP as follows: !> if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j; !> if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n. !>
[out]	INFO	!> INFO is INTEGER !> = 0: successful exit !> < 0: if INFO = -i, the i-th argument had an illegal value !>

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.