f01vl copies a real triangular matrix stored in a Rectangular Full Packed (RFP) format to packed format. The RFP storage format is described in [] in the F07 class Chapter Introduction and the packed storage format is described in [] in the F07 class Chapter Introduction.

Syntax

C#
```public static void f01vl(
string transr,
string uplo,
int n,
double[] arf,
double[] ap,
out int info
)```
Visual Basic
```Public Shared Sub f01vl ( _
transr As String, _
uplo As String, _
n As Integer, _
arf As Double(), _
ap As Double(), _
<OutAttribute> ByRef info As Integer _
)```
Visual C++
```public:
static void f01vl(
String^ transr,
String^ uplo,
int n,
array<double>^ arf,
array<double>^ ap,
[OutAttribute] int% info
)```
F#
```static member f01vl :
transr : string *
uplo : string *
n : int *
arf : float[] *
ap : float[] *
info : int byref -> unit
```

Parameters

transr
Type: System..::..String
On entry: specifies whether the RFP representation of $A$ is normal or transposed.
${\mathbf{transr}}=\text{"N"}$
The matrix $A$ is stored in normal RFP format.
${\mathbf{transr}}=\text{"T"}$
The matrix $A$ is stored in transposed RFP format.
Constraint: ${\mathbf{transr}}=\text{"N"}$ or $\text{"T"}$.
uplo
Type: System..::..String
On entry: specifies whether $A$ is upper or lower triangular.
${\mathbf{uplo}}=\text{"U"}$
$A$ is upper triangular.
${\mathbf{uplo}}=\text{"L"}$
$A$ is lower triangular.
Constraint: ${\mathbf{uplo}}=\text{"U"}$ or $\text{"L"}$.
n
Type: System..::..Int32
On entry: $n$, the order of the matrix $A$.
Constraint: ${\mathbf{n}}\ge 0$.
arf
Type: array<System..::..Double>[]()[][]
An array of size [${\mathbf{n}}×\left({\mathbf{n}}+1\right)/2$]
On entry: the triangular matrix $A$ in RFP format, as described in [] in the F07 class Chapter Introduction.
ap
Type: array<System..::..Double>[]()[][]
An array of size [${\mathbf{n}}×\left({\mathbf{n}}+1\right)/2$]
On exit: the $n$ by $n$ triangular matrix $A$, packed by columns.
More precisely,
• if ${\mathbf{uplo}}=\text{"U"}$, the upper triangle of $A$ is stored with element ${A}_{ij}$ in ${\mathbf{ap}}\left[i+j\left(j-1\right)/2\right]$ for $i\le j$;
• if ${\mathbf{uplo}}=\text{"L"}$, the lower triangle of $A$ is stored with element ${A}_{ij}$ in ${\mathbf{ap}}\left[i+\left(2n-j\right)\left(j-1\right)/2\right]$ for $i\ge j$.
info
Type: System..::..Int32%
On exit: ${\mathbf{info}}=0$ unless the method detects an error (see [Error Indicators and Warnings]).

Description

f01vl packs a real $n$ by $n$ triangular matrix $A$ stored in RFP format to packed format. This method is intended for possible use in conjunction with methods from F06 class F07 class where some methods that use triangular matrices store them in RFP format.

None.

Error Indicators and Warnings

${\mathbf{info}}<0$
If ${\mathbf{info}}=-i$, argument $i$ had an illegal value. An explanatory message is output, and execution of the program is terminated.
${\mathbf{ifail}}=-9000$
An error occured, see message report.
${\mathbf{ifail}}=-6000$
Invalid Parameters $〈\mathit{\text{value}}〉$
${\mathbf{ifail}}=-8000$
Negative dimension for array $〈\mathit{\text{value}}〉$
${\mathbf{ifail}}=-6000$
Invalid Parameters $〈\mathit{\text{value}}〉$

Not applicable.

None.

None.

Example

This example reads in a triangular matrix in RFP format and copies it to packed format.

Example program (C#): f01vle.cs

Example program data: f01vle.d

Example program results: f01vle.r