数组常用操作实现

    /**
     * 求数组中的最大值
     * 
     * @param a
     */
    public double maxElement(double a[]) {
        double max = a[0];
        for (int i = 0; i < a.length; i++) {
            if (a[i] > max) {
                max = a[i];
            }
        }
        return max;
    }

    /**
     * 求数组中的平均值
     * 
     * @param a
     */
    public double average(double a[]) {
        int len = a.length;
        double sum = 0.0;
        for (int i = 0; i < len; i++) {
            sum += a[i];
        }
        return sum / len;
    }

    /**
     * 复制数组
     * @param a
     */
    public void copyArray(double a[]) {
        int len = a.length;
        double[] b = new double[len];
        for (int i = 0; i < len; i++) {
            b[i] = a[i];
        }
    }
    
    /**
     * 数组反转
     * @param a
     */
    public void reverse(double a[]){
        int len = a.length;
        for(int i=0;i<len/2;i++){
             double temp = a[i];
             a[i] = a[len-1-i];
             a[len-1-i] = temp;
        }
    }