Question about normalizing values

Question

Hey guys,
I have this code here that reads in odometer reading from two vehicles and plots them.
Here is my question
since each vehicle has its own starting values such as 85K miles or 15K miles...
How would i normalize the initial odometer reading at 0 and loop through the other values with the same proportion?...
Here's the code I have :
public void plotDataset(String label, TimeSeriesCollection tsc,
                               dataSet ds) {
    String dsName = ds.majorDescriptor;
    dbg("processing " + dsName);
    TimeSeries ts = new TimeSeries(label, Day.class);
    int dsSize = ds.size();
    for (int i=0; i<dsSize; i++) {
      dataEl el   = ds.get(i);
      double val  = el.getMainValue();  
      Date   date = el.getDateJava();
      ts.addOrUpdate(new Day(date), val);
     tsc.addSeries(ts);
  }

Answer 1

spoon_ wrote:
Jazman wrote:
This doesn't make sense to me. What it seems to be saying is create an object of type StringWriter and pass a copy of this object to an invoke method. Then pass a copy to the filter method and set the return value to a String call output. However before you pass a copy to the filter method convert it to a String.Objects are not values in Java. "stringWriter" is a reference to a StringWriter object. In your other example "i" is a reference to a String object. A reference is kind of like a pointer in C.
Edited by: spoon_ on Dec 27, 2007 5:44 PMOkay so i is a reference, but then if that reference is passed onto another method doesn't that method instantiate its own copy of that reference, i.e. create a new reference pointing to a new object. That is why the value of String i doesn't change when you pass it to the method.
However the value of stringWriter in the example given below does change;
public class test2 {
    public static void main(String[] args) {
        StringBuilder i = new StringBuilder("Hello");
        System.out.println("The value of i is "+i);
        addOne(i);
        System.out.println("The value of i is now "+i);
    public static void addOne(StringBuilder i){
        i.append("Goodbye");
}why is it that the value of stringWriter is changed when you pass it to a method and the value of String i isn't changed when you pass it through a method?