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java comment // Program 11.6: A nicer sine wave
java code import java.applet.Applet;
java code import java.awt.Graphics;
java blank
java code public class SineApplet2 extends Applet {
java blank
java code public void paint(Graphics g) {
java blank
java code int i, j1, j2;
java blank
java code j1 = yvalue(0);
java code for (i = 0; i < size().width; i++) {
java code j2 = yvalue(i+1);
java code g.drawLine(i, j1 ,i+1, j2);
java code j1 = j2;
java code }
java blank
java code }
java blank
java comment // Given the xpoint we're given calculate the Cartesian equivalent
java code private int yvalue(int ivalue) {
java blank
java code double xmin = -10.0;
java code double xmax = 10.0;
java code double ymin = -1.0;
java code double ymax = 1.0;
java code double x, y;
java code int jvalue;
java blank
java code x = (ivalue * (xmax - xmin)/(size().width - 1)) + xmin;
java blank
java comment // Take the sine of that x
java code y = Math.sin(x);
java blank
java comment // Scale y into window coordinates
java code jvalue = (int) ((y - ymin)*(size().height - 1)/
java code (ymax - ymin));
java blank
java comment /* Switch jvalue from Cartesian coordinates
java comment to computer graphics coordinates */
java code jvalue = size().height - jvalue;
java blank
java code return jvalue;
java blank
java code }
java blank
java code }
java blank
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