Moving Average : Math Functions « Development « Java Tutorial

Copyright (c) 2007 Erik Bengtson and others. All rights reserved. 
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you may not use this file except in compliance with the License.
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import java.util.LinkedList;

 * Math Utilities.
public class MathUtils
     * Simple Moving Average
    public static class SMA
        private LinkedList values = new LinkedList();

        private int length;

        private double sum = 0;

        private double average = 0;
         * @param length the maximum length
        public SMA(int length)
            if (length <= 0)
                throw new IllegalArgumentException("length must be greater than zero");
            this.length = length;

        public double currentAverage()
            return average;

         * Compute the moving average.
         * Synchronised so that no changes in the underlying data is made during calculation.
         * @param value The value
         * @return The average
        public synchronized double compute(double value)
            if (values.size() == length && length > 0)
                sum -= ((Double) values.getFirst()).doubleValue();
            sum += value;
            values.addLast(new Double(value));
            average = sum / values.size();
            return average;

6.17.Math Functions
6.17.1.Math Class Methods
6.17.2.Use math functions
6.17.3.Testing the Math class methods
6.17.4.Floating Point Number Enhancements in JDK 6
6.17.10.Demonstrate toDegrees() and toRadians().
6.17.11.Find absolute value of float, int, double and long using Math.abs
6.17.12.Find ceiling value of a number using Math.ceil
6.17.13.Find exponential value of a number using Math.exp
6.17.14.Find floor value of a number using Math.floor
6.17.15.Find maximum of two numbers using Math.max
6.17.16.Find natural logarithm value of a number using Math.log
6.17.17.Find power using Math.pow
6.17.18.Find square root of a number using Math.sqrt
6.17.19.Round Java float and double numbers using Math.round
6.17.21.Normalizes an angle to a relative angle.
6.17.22.Normalizes an angle to an absolute angle.
6.17.23.Normalizes an angle to be near an absolute angle
6.17.24.Calculate the floor of the log, base 2
6.17.25.Greatest Common Divisor (GCD) of positive integer numbers
6.17.26.Least Common Multiple (LCM) of two strictly positive integer numbers
6.17.27.Moving Average
6.17.28.Normalize an angle in a 2&pi wide interval around a center value.
6.17.29.Returns n!. Shorthand for n Factorial, the product of the numbers 1,...,n as a double.
6.17.30.Returns n!. Shorthand for n Factorial, the product of the numbers 1,...,n.
6.17.31.Returns the hyperbolic cosine of x.
6.17.32.Returns the hyperbolic sine of x.
6.17.33.Returns the natural log of the ( Binomial Coefficient
6.17.34.Returns the natural logarithm of n!.
6.17.35.Round the given value to the specified number of decimal places. The value is rounded using the BigDecimal.ROUND_HALF_UP method.
6.17.36.Value is rounded using the given method which is any method defined in BigDecimal
6.17.37.sqrt(a^2 + b^2) without under/overflow