NAG Library Function Document

nag_rngs_init_repeatable (g05kbc)

1  Purpose

2  Specification

3  Description

4  References

5  Arguments

1:     igen – Integer *Input/Output

On entry: must contain the identification number for the generator to be used to return a pseudorandom number and should remain unchanged until a re-initialization by a call to one of the functions nag_rngs_init_repeatable (g05kbc) or nag_rngs_init_nonrepeatable (g05kcc). The values that may be chosen are:

• $\mathbf{igen}=0$, the basic generator;
• $1\le \mathbf{igen}\le 273$, a Wichman–Hill generator.

See the g05 Chapter Introduction for details.

On exit: if $\mathbf{igen}<0$ on input then igen is set to $0$, if $\mathbf{igen}>273$ on input then igen is set to $\left(\mathbf{igen}-1\right)\mathrm{ mod }273+1$.

2:     iseed[$4$] – IntegerCommunication Array

On entry: must contain values which are used to obtain an initial state for the generator selected by the argument igen. The treatment of the array iseed differs depending on the value of igen input. As a result, the requirements for meaningful values of the elements of iseed also depend on igen; these requirements are as follows:

• if $\mathbf{igen}=0$, only $\mathbf{iseed}\left[0\right]$ need be set to any non-negative integer;
• otherwise, all elements of iseed must be set and should be positive and are recommended to be at least five digits in length.

On exit: contains initial seeds for the selected generator.

6  Error Indicators and Warnings

7  Accuracy

8  Further Comments

9  Example

9.1  Program Text

Program Text (g05kbce.c)

9.2  Program Data

9.3  Program Results

Program Results (g05kbce.r)