Graphs and Maths

Question

not got a clue about this probably very easy thing so pleeeeeease help me.
i have to make a graph which displays "y=A*sin(x)+B*cos(X)" where i can select diferent values for a and b. how am i supposed to do this? what do i use? i dont even know where to start so even the basics will do. cheers 4 any help.

Answer 1

This topic is absolutelly not for a java begginer. It should match more to a somewhat advanced "computer graphics in java" course. Anyway, you need a component to draw into (a Canvas for example). Its paint method should look something like this:
public void paint(Graphics g){
//draw the label
g.setColor(Color.black);
Dimension d = this.getSize();
String lab = " y = "+a+"*sin(x) + "+b+"*cos(x)";
g.drawString(lab,50,20);
//draw the axes
g.drawString("y",60,45);
g.drawString("x",d.width-60,d.height-40);
g.drawLine(50,50,50,d.height-50);
g.drawLine(50,d.height/2,d.width-50,d.height/2);
double maxx = d.width-140;
//draw the curve
g.setColor(Color.red);
for(x=0.0; x<2*Math.PI; x+=0.01){
     y = a*Math.sin(x) + b*Math.cos(x);
     int x1 = (int)((x*maxx/(2*Math.PI))+50);
     int y1 = (int)(d.height/2 - y*125);
     g.drawLine(x1,y1,x1,y1);
.....assuming that you have initialized somehow the values of a and b...
Good luck....