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Ulm's Oberon Library:
PrimeGen

NAME

PrimeGen - implementation of a prime number generator

SYNOPSIS

PROCEDURE Generate(test: Primes.Test; n: INTEGER; 
                   pLeast: REAL;
                   VAR prime: IntOperations.Operand);

DESCRIPTION

PrimeGen is an implementation of a prime number generator using QuickPrimeTest to speed up the generation, and a probabilistic testing algorithm given as a parameter (see Lehmann and RabinMiller). Prime number generation, particularly if large prime numbers are wanted, is time-consuming. Large prime numbers means for example n set to 512.

Generate generates a prime number in $[ 2 sup {n-1}..2 sup n )$. The probability that the generated number is prime is greater or equal than pLeast. test specifies the used probabilistic testing algorithm and the result is stored in the already initialized value prime which must be large enough for n bits (check with IntOperations.IsLargeEnoughFor).

DIAGNOSTICS

PrimeGen asserts that the variable used for storing the prime number is already initialized and that the type of prime is large enough for n bits.

AUTHOR

Frank B.J. Fischer