h02bvf prints the solution to a linear or integer programming problem computed by e04mff/e04mfa or h02bbf and h02bzf, with user-supplied names for the rows and columns.

2 Specification

Fortran Interface

Subroutine h02bvf (

n, m, a, lda, bl, bu, x, clamda, istate, crname, ifail)

Integer, Intent (In)	::	n, m, lda, istate(n+m)
Integer, Intent (Inout)	::	ifail
Real (Kind=nag_wp), Intent (In)	::	a(lda,*), bl(n+m), bu(n+m), x(n), clamda(n+m)
Character (8), Intent (In)	::	crname(n+m)

C Header Interface

#include <nag.h>

void	h02bvf_ (const Integer n, const Integer m, const double a[], const Integer lda, const double bl[], const double bu[], const double x[], const double clamda[], const Integer istate[], const char crname[], Integer ifail, const Charlen length_crname)

The routine may be called by the names h02bvf or nagf_mip_ilp_print.

3 Description

h02bvf prints the solution to a linear or integer programming problem with user-supplied names for the rows and columns. All output is written to the current advisory message unit (as defined by x04abf). The routine must be preceded in the same program by calls to h02buf and either e04mff/e04mfa (if an LP problem has been solved) or h02bbf and h02bzf (if an IP problem has been solved). The documents for e04mff/e04mfa, h02buf and/or h02bbf and h02bzf should be consulted for further details.

4 References

IBM (1971) MPSX – Mathematical programming system Program Number 5734 XM4 IBM Trade Corporation, New York

5 Arguments

1: $n$ – Integer Input: On entry: the number of variables, as returned by h02buf.

Constraint: $n > 0$ .
2: $m$ – Integer Input: On entry: the number of general linear constraints, as returned by h02buf.

Constraint: $m \geq 0$ .
3: $a (lda, *)$ – Real (Kind=nag_wp) array Input: Note: the second dimension of the array a must be at least $n$ if $m > 0$ and at least $1$ if $m = 0$ .

On entry: the matrix of general linear constraints, as returned by h02buf.
4: $lda$ – Integer Input: On entry: this must be the same argument maxm as supplied to h02buf.

Constraint: $lda \geq \max (1, m)$ .
5: $bl (n + m)$ – Real (Kind=nag_wp) array Input: On entry: the lower bounds for all the constraints, as returned by e04mff/e04mfa or h02bzf.
6: $bu (n + m)$ – Real (Kind=nag_wp) array Input: On entry: the upper bounds for all the constraints, as returned by e04mff/e04mfa or h02bzf.
7: $x (n)$ – Real (Kind=nag_wp) array Input: On entry: the solution to the problem, as returned by e04mff/e04mfa or h02bbf.
8: $clamda (n + m)$ – Real (Kind=nag_wp) array Input: On entry: the Lagrange-multipliers (reduced costs) for each constraint with respect to the working set, as returned by e04mff/e04mfa or h02bzf.
9: $istate (n + m)$ – Integer array Input: On entry: the status of every constraint in the working set at the solution, as returned by e04mff/e04mfa or h02bzf.
10: $crname (n + m)$ – Character(8) array Input: On entry: the user-defined names for all the variables and constraints, as returned by h02buf.
11: $ifail$ – 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

−1

, explanatory error messages are output on the current error message unit (as defined by x04aaf).

Errors or warnings detected by the routine:

$ifail = 1$: On entry, $lda = ⟨ value ⟩$ and $m = ⟨ value ⟩$ .
Constraint: $lda \geq \max (1, m)$ .

On entry, $m = ⟨ value ⟩$ .
Constraint: $m \geq 0$ .

On entry, $n = ⟨ value ⟩$ .
Constraint: $n > 0$ .

$ifail = - 99$: 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.

$ifail = - 399$: 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.

$ifail = - 999$: 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

Background information to multithreading can be found in the Multithreading documentation.

h02bvf is not thread safe and should not be called from a multithreaded user program. Please see Section 1 in FL Interface Multithreading for more information on thread safety.

h02bvf makes calls to BLAS and/or LAPACK routines, which may be threaded within the vendor library used by this implementation. Consult the documentation for the vendor library for further information.

Please consult the X06 Chapter Introduction for information on how to control and interrogate the OpenMP environment used within this routine. Please also consult the Users' Note for your implementation for any additional implementation-specific information.