DistDiscreteUniform.java
package nl.tudelft.simulation.jstats.distributions;
import org.djutils.exceptions.Throw;
import nl.tudelft.simulation.jstats.streams.StreamInterface;
/**
* The discrete Uniform distribution. For more information on this distribution see
* <a href="https://mathworld.wolfram.com/UnifomrDistribution.html"> https://mathworld.wolfram.com/UniformDistribution.html </a>
* <p>
* Copyright (c) 2002-2024 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See
* for project information <a href="https://simulation.tudelft.nl/" target="_blank"> https://simulation.tudelft.nl</a>. The DSOL
* project is distributed under a three-clause BSD-style license, which can be found at
* <a href="https://https://simulation.tudelft.nl/dsol/docs/latest/license.html" target="_blank">
* https://https://simulation.tudelft.nl/dsol/docs/latest/license.html</a>.
* </p>
* @author <a href="https://www.linkedin.com/in/peterhmjacobs">Peter Jacobs </a>
* @author <a href="https://www.tudelft.nl/averbraeck">Alexander Verbraeck</a>
*/
public class DistDiscreteUniform extends DistDiscrete
{
/** */
private static final long serialVersionUID = 1L;
/** min is the minimum value of this distribution. */
private final long min;
/** max is the maximum value of this distribution. */
private final long max;
/**
* constructs a new discrete uniform distribution, such as throwing dice with possible outcomes 1..6. Random occurrence with
* several possible outcomes, each of which is equally likely.
* @param stream StreamInterface; the random number stream
* @param min long; the minimal value
* @param max long; the maximum value
* @throws IllegalArgumentException when min >= max
*/
public DistDiscreteUniform(final StreamInterface stream, final long min, final long max)
{
super(stream);
Throw.when(min >= max, IllegalArgumentException.class, "Error Discrete Uniform - min >= max");
this.min = min;
this.max = max;
}
/** {@inheritDoc} */
@Override
public long draw()
{
return this.stream.nextInt((int) this.min, (int) this.max);
}
/** {@inheritDoc} */
@Override
public double probability(final long observation)
{
if (observation >= this.min && observation <= this.max)
{
return 1 / ((double) this.max - this.min + 1);
}
return 0.0;
}
/**
* @return min
*/
public long getMin()
{
return this.min;
}
/**
* @return max
*/
public long getMax()
{
return this.max;
}
/** {@inheritDoc} */
@Override
public String toString()
{
return "DiscreteUniform(" + this.min + "," + this.max + ")";
}
}