hide long namesshow long names
hide short namesshow short names
Integer type:  int32  int64  nag_int  show int32  show int32  show int64  show int64  show nag_int  show nag_int

PDF version (NAG web site, 64-bit version, 64-bit version)
Chapter Contents
Chapter Introduction
NAG Toolbox

NAG Toolbox: nag_sort_permute_check (m01zb)

 Contents

    1  Purpose
    2  Syntax
    7  Accuracy
    9  Example

Purpose

nag_sort_permute_check (m01zb) checks the validity of a permutation.

Syntax

[iperm, ifail] = m01zb(iperm, m1, 'm2', m2)
[iperm, ifail] = nag_sort_permute_check(iperm, m1, 'm2', m2)

Description

nag_sort_permute_check (m01zb) can be used to check the validity of user-supplied ranks or indices, without the ranks or indices being corrupted.

References

None.

Parameters

Compulsory Input Parameters

1:     ipermm2 int64int32nag_int array
Elements m1 to m2 of iperm must be set to values which are supposed to be a permutation of the integers m1 to m2. If they are a valid permutation, the function exits with ifail=0.
2:     m1 int64int32nag_int scalar
The range of elements used in the array iperm and the range of values in the permutation, as specified under iperm.
Constraint: 0<m1m2.

Optional Input Parameters

1:     m2 int64int32nag_int scalar
Default: the dimension of the array iperm.
The range of elements used in the array iperm and the range of values in the permutation, as specified under iperm.
Constraint: 0<m1m2.

Output Parameters

1:     ipermm2 int64int32nag_int array
Used as internal workpsace prior to being restored and hence is unchanged.
2:     ifail int64int32nag_int scalar
ifail=0 unless the function detects an error (see Error Indicators and Warnings).

Error Indicators and Warnings

Errors or warnings detected by the function:
   ifail=1
On entry,m2<1,
orm1<1,
orm1>m2.
   ifail=2
Elements m1 to m2 of iperm contain a value outside the range m1 to m2.
   ifail=3
Elements m1 to m2 of iperm contain a repeated value.
   ifail=-99
An unexpected error has been triggered by this routine. Please contact NAG.
   ifail=-399
Your licence key may have expired or may not have been installed correctly.
   ifail=-999
Dynamic memory allocation failed.
If ifail=2 or 3, elements m1 to m2 of iperm do not contain a permutation of the integers m1 to m2.

Accuracy

Not applicable.

Further Comments

None.

Example

This example reads in a vector of real numbers, and a vector of ranks; it calls nag_sort_permute_check (m01zb) to check the validity of the ranks before calling nag_sort_realvec_rank_rearrange (m01ea) to rearrange the real numbers into the specified order.
function m01zb_example


fprintf('m01zb example results\n\n');

rv    = [      5.3  4.6  7.8 1.7 5.3  9.9 3.2 4.3  7.8 4.5 1.2 7.6];
iperm = [int64(7) 6   10   2   8   12   3   4   11   5   1   9];

m1 = int64(1);
[iperm, ifail] = m01zb(iperm, m1);

[rv, iperm, ifail] = m01ea(rv, m1, iperm);

disp('Numbers in rank order');
fprintf('%5.1f%5.1f%5.1f%5.1f%5.1f%5.1f\n',rv);


m01zb example results

Numbers in rank order
  1.2  1.7  3.2  4.3  4.5  4.6
  5.3  5.3  7.6  7.8  7.8  9.9

PDF version (NAG web site, 64-bit version, 64-bit version)
Chapter Contents
Chapter Introduction
NAG Toolbox

© The Numerical Algorithms Group Ltd, Oxford, UK. 2009–2015