COS126

• Download MovingAverage3.java

/******************************************************************************
  *  Name:    Reference Solution
  *  NetID:   ref
  *  Precept: P00
  *
  *  Partner Name:    N/A
  *  Partner NetID:   N/A
  *  Partner Precept: N/A
  *
  *  Description:  Reads, prints, and plots stock prices.
  *
  *                Computes 3-day simple moving average starting on the 3rd
  *                day. Plots and prints stock price data and moving average.
  *
  *  Example:      java-introcs MovingAverage3 < TSLA.txt
  *
  ******************************************************************************/

public class MovingAverage3 {
    public static void main(String[] args) {

        // Number of trading days
        int n = StdIn.readInt();
        int DAYS = 3;

        // parallel arrays
        String[] date  = new String[n];
        double[] open  = new double[n];
        double[] high  = new double[n];
        double[] low   = new double[n];
        double[] close = new double[n];
        double[] ma   = new double[n];

        // Read in daily prices
        for (int i = 0; i < n; i++) {
            date[i]  = StdIn.readString();
            open[i]  = StdIn.readDouble();
            high[i]  = StdIn.readDouble();
            low[i]   = StdIn.readDouble();
            close[i] = StdIn.readDouble();


            // compute moving average if needed
            if (i >= DAYS - 1) {
                // sum of previous 3 days
                double sum = 0;
                for (int j = i; j > i - DAYS; j--) {
                    sum += close[j];
                }
                // compute moving average
                ma[i] = sum / DAYS;
            }

        }

        // Plot stock price data
        StockPlot.plot(open, high, low, close, ma, DAYS);

        // Output the information
        StdOut.println(n);
        for (int i = 0; i < n; i++) {
            StdOut.printf("%s %.2f %.2f %.2f %.2f",
                          date[i], open[i], high[i], low[i], close[i]);
            if (i >= DAYS - 1)
                StdOut.printf(" %.2f", ma[i]);
            StdOut.println();
        }
    }
}