How to calculate position on a circle with a certain angle?

Question

I\'m trying to figure out how I could be able to calculate coordinates on a circle. For simplicity I made some images.

Answer 1

Thats how:

private PointF getPosition(PointF center, float radius, float angle) {

    PointF p = new PointF((float) (center.x + radius * Math.cos(Math.toRadians(angle))),
    (float) (center.y + radius* Math.sin(Math.toRadians(angle))));

    return p;
}

This method calculates the position around the center of a circle (center of your view) depending on radius and angle. Angle in degrees.

The returned PointF will contain the x- and y-coordinate of the calculated position.

Be aware that 0 degrees is at the very east position of the circle, 270 degrees is in the very north position of the circle:

So if the center of your view is at x: 100, y: 100 and you calculate the position with an angle of 0 degrees and a radius of 50, the result will be x: 150, y: 100

If you use angle 90 degrees and radius 50, the result will be x: 100, y: 150

It is used here in my charting libary, and it works.