g05 Chapter Contents
g05 Chapter Introduction
NAG C Library Manual

NAG Library Function Documentnag_rand_logical (g05tbc)

1  Purpose

nag_rand_logical (g05tbc) generates a vector of pseudorandom logical values – Nag_TRUE with probability $p$ and Nag_FALSE with probability $\left(1-p\right)$.

2  Specification

 #include #include
 void nag_rand_logical (Integer n, double p, Integer state[], Nag_Boolean x[], NagError *fail)

3  Description

nag_rand_logical (g05tbc) generates $n$ logical values ${x}_{i}$ from the relation
 $yi
where ${y}_{i}$ is a pseudorandom number from a uniform distribution over $\left(0,1\right]$, generated by nag_rand_basic (g05sac) using the values of state as input to this function.
One of the initialization functions nag_rand_init_repeatable (g05kfc) (for a repeatable sequence if computed sequentially) or nag_rand_init_nonrepeatable (g05kgc) (for a non-repeatable sequence) must be called prior to the first call to nag_rand_logical (g05tbc).

4  References

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

5  Arguments

1:     nIntegerInput
On entry: $n$, the number of pseudorandom logical values to be generated.
Constraint: ${\mathbf{n}}\ge 0$.
2:     pdoubleInput
On entry: must contain the probability of nag_rand_logical (g05tbc) returning Nag_TRUE.
Constraint: $0.0\le {\mathbf{p}}\le 1.0$.
3:     state[$\mathit{dim}$]IntegerCommunication Array
Note: the actual argument supplied must be the array state supplied to the initialization functions nag_rand_init_repeatable (g05kfc) or nag_rand_init_nonrepeatable (g05kgc).
On entry: contains information on the selected base generator and its current state.
On exit: contains updated information on the state of the generator.
4:     x[n]Nag_BooleanOutput
On exit: the $n$ logical values.
5:     failNagError *Input/Output
The NAG error argument (see Section 3.6 in the Essential Introduction).

6  Error Indicators and Warnings

NE_ALLOC_FAIL
Dynamic memory allocation failed.
On entry, argument $〈\mathit{\text{value}}〉$ had an illegal value.
NE_INT
On entry, ${\mathbf{n}}=〈\mathit{\text{value}}〉$.
Constraint: ${\mathbf{n}}\ge 0$.
NE_INTERNAL_ERROR
An internal error has occurred in this function. Check the function call and any array sizes. If the call is correct then please contact NAG for assistance.
NE_INVALID_STATE
On entry, state vector has been corrupted or not initialized.
NE_REAL
On entry, ${\mathbf{p}}=〈\mathit{\text{value}}〉$.
Constraint: $0.0\le {\mathbf{p}}\le 1.0$.

Not applicable.

None.

9  Example

This example prints the first $20$ pseudorandom logical values generated by nag_rand_logical (g05tbc) after initialization by nag_rand_init_repeatable (g05kfc), when the probability of a Nag_TRUE value is $0.5$.

9.1  Program Text

Program Text (g05tbce.c)

None.

9.3  Program Results

Program Results (g05tbce.r)