import javax.swing.*;

public class Variance
{
	public static void main(String[] args)
	{
		// code for algorithm goes here
		
		// declare and initialize the inputs
		
		double data1 = 0.320;
		double data2 = 0.270;
		double data3 = 0.310;
		
		double mean;
		double variance;
		
		// compute the mean -- this intermediate value is a
                // variable because we use it so often
		
		mean = (data1 + data2 + data3) / 3;
		
		// compute the variance using variables to hold
		// intermediate results so the expression
                // for variance is easier to read
		
		double var1 = (data1 - mean) * (data1 - mean);
		double var2 = (data2 - mean) * (data2 - mean);
		double var3 = (data3 - mean) * (data3 - mean);
		
		variance = (var1 + var2 + var3) / 3;

		// display the result

		System.out.println(variance);
	}
}

This code can also be downloaded from the file Variance.java.