如何绘制一个简单的图形？

Question

So here's the thing, I'm supposed to read a document and import some data. A line in the document looks like this "A 0 2 5 20 23 25." (.txt).

I can write a method that finds this line and the values but my problem is to draw the actual graph whith the values. X of the graph will be fixed for 10 between each value and the values in the file corresponds to Y. I want to come up with a method that takes the first Y(0), and Draws a straight line to the next Y(2) and from 2-5 etc. I fail to do this, my method only Draws a line from 0-2 and 5-20 and 23-25. Book hasn't talked about array's yet so I should do this without arrays, I try to do it as I read the file but..

Here is a bit of my code anyway, any tips?? Much appreciated

public static void drawGraph(String letter, Scanner input, Graphics g){
   while (input.hasNextLine()){
     int x = 1;
     String text = input.nextLine();
     Scanner data = new Scanner(text);
     String foundLetter = data.next();       
     if(foundLetter.equalsIgnoreCase(letter)){
        while(data.hasNextInt()){                 
           int count = data.nextInt();
            //This is where I get Stuck

            g.drawLine((x-1)*10, y1, 10*x);
            x++;

          }

     }
  }

}

I have made an template drawingpanel for the plot divided into sections of 10's

Thanks,

Answer 1

You have to memorize the last y value, then draw a line from (x-1, last y) to (x, y) .

int lastY = data.nextInt();
while (data.hasNextInt()) {                 
    int nextY = data.nextInt();
    g.drawLine((x-1)*10, lastY, 10*x, nextY);
    x++;
    lastY = nextY;
}