# dtpttr.f man page

dtpttr.f

## Synopsis

### Functions/Subroutines

subroutine **dtpttr** (UPLO, **N**, AP, A, **LDA**, INFO)**DTPTTR** copies a triangular matrix from the standard packed format (TP) to the standard full format (TR).

## Function/Subroutine Documentation

### subroutine dtpttr (character UPLO, integer N, double precision, dimension( * ) AP, double precision, dimension( lda, * ) A, integer LDA, integer INFO)

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

**Purpose:**

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

**Parameters:***UPLO*UPLO is CHARACTER*1 = 'U': A is upper triangular. = 'L': A is lower triangular.

*N*N is INTEGER The order of the matrix A. N >= 0.

*AP*AP is DOUBLE PRECISION array, dimension ( N*(N+1)/2 ), On entry, 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.

*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.

*LDA*LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N).

*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.

**Date:**December 2016

Definition at line 106 of file dtpttr.f.

## Author

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

The man page dtpttr(3) is an alias of dtpttr.f(3).

Tue Nov 14 2017 Version 3.8.0 LAPACK