DTRTTP(3)
copies a triangular matrix A from full format (TR) to standard packed format (TP)
SYNOPSIS
 SUBROUTINE DTRTTP(

UPLO, N, A, LDA, AP, INFO )

CHARACTER
UPLO

INTEGER
INFO, N, LDA

DOUBLE
PRECISION A( LDA, * ), AP( * )
PURPOSE
DTRTTP copies a triangular matrix A from full format (TR) to standard
packed format (TP).
ARGUMENTS
 UPLO (input) CHARACTER

= 'U': A is upper triangular.
= 'L': A is lower triangular.
 N (input) INTEGER

The order of the matrices AP and A. N >= 0.
 A (input) DOUBLE PRECISION array, dimension (LDA,N)

On exit, the triangular matrix A. If UPLO = 'U', the leading
NbyN 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 NbyN 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.
 LDA (input) INTEGER

The leading dimension of the array A. LDA >= max(1,N).
 AP (output) DOUBLE PRECISION array, dimension (N*(N+1)/2

On exit, the upper or lower triangular matrix A, packed
columnwise in a linear array. The jth column of A is stored
in the array AP as follows:
if UPLO = 'U', AP(i + (j1)*j/2) = A(i,j) for 1<=i<=j;
if UPLO = 'L', AP(i + (j1)*(2nj)/2) = A(i,j) for j<=i<=n.
 INFO (output) INTEGER

= 0: successful exit
< 0: if INFO = i, the ith argument had an illegal value