Fall 2018, Siena College

Distance BlueJ Project

Distance Source Code

The Java source code for Distance is below. Click on a file name to download it.

### Distance.java

/*
* Example Distance -- includes a method that returns the distance
* between two points in the plane
*
* Jim Teresco, The College of Saint Rose, CSC 202, Fall 2012
* Updated for Siena College, CSIS 210, Fall 2016
*
* \$Id\$
*/

import java.text.DecimalFormat;
import java.util.Random;

public class Distance {

// a method to compute the distance between two points -- takes 4 parameters
// first two are (x,y) of one point, last two are (x,y) of the other
public static double distance(double x1, double y1, double x2, double y2) {

double xDiff = x1 - x2;
double yDiff = y1 - y2;

return Math.sqrt(xDiff*xDiff + yDiff*yDiff);
}

// a main method to try this out
public static void main(String[] args) {

// compute the distance between the origin and (1,0)
double dist1 = distance(0,0,1,0);
System.out.println("(0,0) to (1,0) is " + dist1);

// compute the distance between the origin and (1,1)
double dist2 = distance(0,0,1,1);
System.out.println("(0,0) to (1,1) is " + dist2);

// we can print the result immediately without storing it in a
// variable
System.out.println("(3,4) to (-2,9.7) is " + distance(3,4,-2,9.7));

// setup for random number generation and result formatting
Random randGen = new Random();
DecimalFormat df = new DecimalFormat("0.000");

// now we'll compute some random distances between points in
// (0,0) to (1,1)
for (int count = 0; count < 10; count++) {
// it's important that we generate and save random numbers
// in variables for our points, because we want to make
// sure we use the SAME random numbers for both the
// distance computation and the printout of the points!
double x1 = randGen.nextDouble();
double y1 = randGen.nextDouble();
double x2 = randGen.nextDouble();
double y2 = randGen.nextDouble();
System.out.println("(" + df.format(x1) + "," + df.format(y1) +
") to (" + df.format(x2) + "," +
df.format(y2) + ") is " +
df.format(distance(x1,y1,x2,y2)));
}

}
}