Random Number Generator Project (ht09)

This project implements a random number generation program, printrandom, which uses two types of random number generators: a Linear Congruential Generator (LCG) and a Mersenne Twister (MT). The program is designed to be compiled with a Makefile, using shared code organization and dynamic linking.

Table of Contents

• Overview
• Compilation
• Usage
• Detailed Description
• Example

Overview

printrandom generates uniformly distributed random numbers in the range [0, 1), with support for two types of random number generators:

1. Linear Congruential Generator (LCG)
2. Mersenne Twister (MT)

The program accepts the generator type, count of numbers to generate, and a seed as command-line arguments. It then initializes the specified generator, produces the requested count of random numbers, and outputs them in a formatted manner.

Compilation

To compile the program, ensure that all files are in the project directory, then run:

make

This will produce an executable called printrandom. To clean up object files and the executable, run:

make clean

Usage

The program requires three command-line arguments:

1. Generator type (mt or linear)
2. Number of random numbers to generate (integer between 0 and 100000)
3. Seed for initializing the generator

Example Usage

./printrandom linear 5 12345

This example runs the program with the Linear Congruential Generator, generating 5 random numbers using the seed 12345.

Detailed Description

Random Number Generators

1. Linear Congruential Generator (LCG):

   • Uses multiplier 1103515245, increment 12345, and modulus 2^31.
   • Seed is specified as a positive integer, with only the lower 31 bits used.

2. Mersenne Twister (MT):

   • Uses a 32-bit Mersenne Twister algorithm.
   • Seed is a 32-bit unsigned integer.
   • As stated in the task, its implementation was taken from here

RandomSource Interface

The RandomSource interface allows seamless switching between different generator implementations. Each generator type implements:

• double next(RandomSource *src): Generates the next random number.
• RandomSource *destroy(RandomSource *src): Cleans up and frees resources associated with the generator.

random_factory Functions

Each generator has a specific factory function to initialize it:

• random_linear_factory: Initializes an LCG generator.
• random_mt_factory: Initializes an MT generator.

The main.c file loads the correct factory function using dlsym based on the command-line argument.

Example

To generate 5 random numbers using the Mersenne Twister generator with seed 123456:

./printrandom mt 5 123456

Expected output:

0.491462737
0.5018269304
0.2805587475
0.2943618261
0.347394317

Each line is a new random number formatted to 10 significant figures.