g05ejf

g05ejf © Numerical Algorithms Group, 2002.

Purpose

G05EJF Pseudo-random sample from an integer vector

Synopsis

[ib,ifail] = g05ejf(ia,m<,ifail>)

Description

 
 The routine selects m elements from vector IA of length n and 
 places them in vector IB. Their order in IA will be preserved in 
                 (n)                                            
 IB. Each of the (m) possible combinations of elements of IA may 
 be regarded as being equiprobable.
 
 If n is greater than 60, it is theoretically impossible that all 
 combinations of size m may occur, unless m is near 1 or near n. 
                 (n)                                        
 This is because (m) exceeds the cycle length of G05CAF. For 
 practical purposes this is irrelevant, as the time taken to 
 generate all possible combinations is many millenia.

Parameters

g05ejf

Required Input Arguments:

ia (:)                                integer
m                                     integer

Optional Input Arguments:                       <Default>

ifail                                 integer  -1

Output Arguments:

ib (m)                                integer
ifail                                 integer