x04cc is an easy-to-use method to print a real triangular matrix stored in a packed one-dimensional array.

Syntax

C#
public static void x04cc(
	string uplo,
	string diag,
	int n,
	double[] a,
	string title,
	out int ifail
)
Visual Basic
Public Shared Sub x04cc ( _
	uplo As String, _
	diag As String, _
	n As Integer, _
	a As Double(), _
	title As String, _
	<OutAttribute> ByRef ifail As Integer _
)
Visual C++
public:
static void x04cc(
	String^ uplo, 
	String^ diag, 
	int n, 
	array<double>^ a, 
	String^ title, 
	[OutAttribute] int% ifail
)
F#
static member x04cc : 
        uplo : string * 
        diag : string * 
        n : int * 
        a : float[] * 
        title : string * 
        ifail : int byref -> unit 

Parameters

uplo
Type: System..::..String
On entry: indicates the type of the matrix to be printed
uplo="L"
The matrix is lower triangular. In this case, the packed array a holds the matrix elements in the following order: 1,1,2,1,,n,1,2,2,3,2,,n,2, etc.
uplo="U"
The matrix is upper triangular. In this case, the packed array a holds the matrix elements in the following order: 1,1,1,2,2,2,1,3,2,3,3,3,1,4, etc.
Constraint: uplo="L" or "U".
diag
Type: System..::..String
On entry: indicates whether the diagonal elements of the matrix are to be printed.
diag="B"
The diagonal elements of the matrix are not referenced and not printed.
diag="U"
The diagonal elements of the matrix are not referenced, but are assumed all to be unity, and are printed as such.
diag="N"
The diagonal elements of the matrix are referenced and printed.
Constraint: diag="B", "U" or "N".
n
Type: System..::..Int32
On entry: the order of the matrix to be printed.
If n is less than 1, x04cc will exit immediately after printing title; no row or column labels are printed.
a
Type: array<System..::..Double>[]()[][]
An array of size [dim1]
Note: the dimension of the array a must be at least max1,n×n+1/2.
On entry: the matrix to be printed. Note that a must have space for the diagonal elements of the matrix, even if these are not stored.
More precisely,
  • if uplo="U", the upper triangle of A must be stored with element Aij in a[i+jj-1/2] for ij;
  • if uplo="L", the lower triangle of A must be stored with element Aij in a[i+2n-jj-1/2] for ij.
If diag="U", the diagonal elements of A are assumed to be 1, and are not referenced; the same storage scheme is used whether diag="N" or ‘U’.
title
Type: System..::..String
On entry: a title to be printed above the matrix.
If title=' ', no title (and no blank line) will be printed.
If title contains more than 80 characters, the contents of title will be wrapped onto more than one line, with the break after 80 characters.
Any trailing blank characters in title are ignored.
ifail
Type: System..::..Int32%
On exit: ifail=0 unless the method detects an error or a warning has been flagged (see [Error Indicators and Warnings]).

Description

x04cc prints a real triangular matrix stored in packed form. It is an easy-to-use driver for (X04CDF not in this release). The method uses default values for the format in which numbers are printed, for labelling the rows and columns, and for output record length. The matrix must be packed by column.
x04cc will choose a format code such that numbers will be printed with an F8.4, an F11.4 or a 1PE13.4 format . The F8.4 code is chosen if the sizes of all the matrix elements to be printed lie between 0.001 and 1.0. The F11.4 code is chosen if the sizes of all the matrix elements to be printed lie between 0.001 and 9999.9999. Otherwise the 1PE13.4 code is chosen.
The matrix is printed with integer row and column labels, and with a maximum record length of 80.
The matrix is output to the unit defined by (X04ABF not in this release).

References

None.

Error Indicators and Warnings

Errors or warnings detected by the method:
ifail=1
On entry,uplo"L" or "U".
ifail=2
On entry,diag"N", "U" or "B".
ifail=-9000
An error occured, see message report.
ifail=-6000
Invalid Parameters value
ifail=-8000
Negative dimension for array value
ifail=-6000
Invalid Parameters value

Accuracy

Not applicable.

Parallelism and Performance

None.

Further Comments

A call to x04cc is equivalent to a call to (X04CDF not in this release) with the following argument values:

Example

The example program calls x04cc twice, first to print a 4 by 4 lower triangular matrix, and then to print a 5 by 5 upper triangular matrix.

Example program (C#): x04cce.cs

Example program results: x04cce.r

See Also