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_rand_logical (g05tb)

## Purpose

nag_rand_logical (g05tb) generates a vector of pseudorandom logical values – true with probability p$p$ and false with probability (1p)$\left(1-p\right)$.

## Syntax

[state, x, ifail] = g05tb(n, p, state)
[state, x, ifail] = nag_rand_logical(n, p, state)

## Description

nag_rand_logical (g05tb) generates n$n$ logical values xi${x}_{i}$ from the relation
 yi < p $yi
where yi${y}_{i}$ is a pseudorandom number from a uniform distribution over (0,1]$\left(0,1\right]$, generated by nag_rand_dist_uniform01 (g05sa) using the values of state as input to this function.
One of the initialization functions nag_rand_init_repeat (g05kf) (for a repeatable sequence if computed sequentially) or nag_rand_init_nonrepeat (g05kg) (for a non-repeatable sequence) must be called prior to the first call to nag_rand_logical (g05tb).

## References

Knuth D E (1981) The Art of Computer Programming (Volume 2) (2nd Edition) Addison–Wesley

## Parameters

### Compulsory Input Parameters

1:     n – int64int32nag_int scalar
n$n$, the number of pseudorandom logical values to be generated.
Constraint: n0${\mathbf{n}}\ge 0$.
2:     p – double scalar
Must contain the probability of nag_rand_logical (g05tb) returning true.
Constraint: 0.0p1.0$0.0\le {\mathbf{p}}\le 1.0$.
3:     state( : $:$) – int64int32nag_int array
Note: the actual argument supplied must be the array state supplied to the initialization routines nag_rand_init_repeat (g05kf) or nag_rand_init_nonrepeat (g05kg).
Contains information on the selected base generator and its current state.

None.

None.

### Output Parameters

1:     state( : $:$) – int64int32nag_int array
Note: the actual argument supplied must be the array state supplied to the initialization routines nag_rand_init_repeat (g05kf) or nag_rand_init_nonrepeat (g05kg).
Contains updated information on the state of the generator.
2:     x(n) – logical array
The n$n$ logical values.
3:     ifail – int64int32nag_int scalar
${\mathrm{ifail}}={\mathbf{0}}$ unless the function detects an error (see [Error Indicators and Warnings]).

## Error Indicators and Warnings

Errors or warnings detected by the function:
ifail = 1${\mathbf{ifail}}=1$
On entry, n < 0${\mathbf{n}}<0$.
ifail = 2${\mathbf{ifail}}=2$
 On entry, p < 0.0${\mathbf{p}}<0.0$, or p > 1.0${\mathbf{p}}>1.0$.
ifail = 3${\mathbf{ifail}}=3$
 On entry, state vector was not initialized or has been corrupted.

Not applicable.

None.

## Example

```function nag_rand_logical_example
% Initialize the seed
seed = [int64(1762543)];
% genid and subid identify the base generator
genid = int64(1);
subid =  int64(1);
n = int64(20);
p = 0.5;
% Initialize the generator to a repeatable sequence
[state, ifail] = nag_rand_init_repeat(genid, subid, seed);
[state, x, ifail] = nag_rand_logical(n, p, state)
```
```

state =

17
1234
1
0
6694
27818
10435
15383
17917
13895
19930
8
0
1234
1
1
1234

x =

0
1
0
0
1
1
1
0
1
0
1
1
0
1
0
1
1
0
0
0

ifail =

0

```
```function g05tb_example
% Initialize the seed
seed = [int64(1762543)];
% genid and subid identify the base generator
genid = int64(1);
subid =  int64(1);
n = int64(20);
p = 0.5;
% Initialize the generator to a repeatable sequence
[state, ifail] = g05kf(genid, subid, seed);
[state, x, ifail] = g05tb(n, p, state)
```
```

state =

17
1234
1
0
6694
27818
10435
15383
17917
13895
19930
8
0
1234
1
1
1234

x =

0
1
0
0
1
1
1
0
1
0
1
1
0
1
0
1
1
0
0
0

ifail =

0

```

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

© The Numerical Algorithms Group Ltd, Oxford, UK. 2009–2013