NAG FL Interface
x04eaf (print_​matrix_​integer)

1 Purpose

x04eaf is an easy-to-use routine to print an integer matrix stored in a two-dimensional array.

2 Specification

Fortran Interface
Subroutine x04eaf ( matrix, diag, m, n, a, lda, title, ifail)
Integer, Intent (In) :: m, n, a(lda,*), lda
Integer, Intent (Inout) :: ifail
Character (*), Intent (In) :: title
Character (1), Intent (In) :: matrix, diag
C Header Interface
#include <nag.h>
void  x04eaf_ (const char *matrix, const char *diag, const Integer *m, const Integer *n, const Integer a[], const Integer *lda, const char *title, Integer *ifail, const Charlen length_matrix, const Charlen length_diag, const Charlen length_title)
The routine may be called by the names x04eaf or nagf_file_print_matrix_integer.

3 Description

x04eaf prints an integer matrix. It is an easy-to-use driver for x04ebf. The routine uses default values for the format in which numbers are printed, for labelling the rows and columns, and for output record length.
x04eaf will choose a format code such that numbers will be printed with the smallest I edit descriptor that is large enough to hold all the numbers to be printed.
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.

4 References


5 Arguments

1: matrix Character(1) Input
On entry: indicates the part of the matrix to be printed.
The whole of the rectangular matrix.
The lower triangle of the matrix, or the lower trapezium if the matrix has more rows than columns.
The upper triangle of the matrix, or the upper trapezium if the matrix has more columns than rows.
Constraint: matrix='G', 'L' or 'U'.
2: diag Character(1) Input
On entry: unless matrix='G', diag must specify whether the diagonal elements of the matrix are to be printed.
The diagonal elements of the matrix are not referenced and not printed.
The diagonal elements of the matrix are not referenced, but are assumed all to be unity, and are printed as such.
The diagonal elements of the matrix are referenced and printed.
If matrix='G', then diag need not be set.
Constraint: if matrix'G', diag='B', 'U' or 'N'.
3: m Integer Input
4: n Integer Input
On entry: the number of rows and columns of the matrix, respectively, to be printed.
If either m or n is less than 1, x04eaf will exit immediately after printing title; no row or column labels are printed.
5: alda* Integer array Input
Note: the second dimension of the array a must be at least max1,n.
On entry: the matrix to be printed. Only the elements that will be referred to, as specified by arguments matrix and diag, need be set.
6: lda Integer Input
On entry: the first dimension of the array a as declared in the (sub)program from which x04eaf is called.
Constraint: ldamax1,m.
7: title Character(*) Input
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.
8: ifail Integer Input/Output
On entry: ifail must be set to 0, -1 or 1 to set behaviour on detection of an error; these values have no effect when no error is detected.
A value of 0 causes the printing of an error message and program execution will be halted; otherwise program execution continues. A value of -1 means that an error message is printed while a value of 1 means that it is not.
If halting is not appropriate, the value -1 or 1 is recommended. If message printing is undesirable, then the value 1 is recommended. Otherwise, the value 0 is recommended. When the value -1 or 1 is used it is essential to test the value of ifail on exit.
On exit: ifail=0 unless the routine detects an error or a warning has been flagged (see Section 6).

6 Error Indicators and Warnings

If on entry ifail=0 or -1, explanatory error messages are output on the current error message unit (as defined by x04aaf).
Errors or warnings detected by the routine:
On entry, matrix is not valid: matrix=value.
On entry, matrix=value, but diag is not valid: diag=value.
On entry, m=value and lda=value.
Constraint: mlda.
An unexpected error has been triggered by this routine. Please contact NAG.
See Section 7 in the Introduction to the NAG Library FL Interface for further information.
Your licence key may have expired or may not have been installed correctly.
See Section 8 in the Introduction to the NAG Library FL Interface for further information.
Dynamic memory allocation failed.
See Section 9 in the Introduction to the NAG Library FL Interface for further information.

7 Accuracy

Not applicable.

8 Parallelism and Performance

x04eaf is not threaded in any implementation.

9 Further Comments

A call to x04eaf is equivalent to a call to x04ebf with the following argument values:

10 Example

This example calls x04eaf twice, first to print a 3 by 5 rectangular matrix, and then to print a 5 by 5 triangular matrix.

10.1 Program Text

Program Text (x04eafe.f90)

10.2 Program Data


10.3 Program Results

Program Results (x04eafe.r)