# dtpttr.f - Man Page

SRC/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

NAG Ltd.

Definition at line 103 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 28 2023 12:08:42 Version 3.12.0 LAPACK