Exponential sine wave

[ErikGee]

Hello!

With this code I can draw a simple sine wave on the stage:

var frequency:Number = 5;
var axisY:Number = stage.stageHeight*.5;
var amplitudeMultiplier:Number = 32;

graphics.lineStyle(2);
graphics.moveTo(0, axisY);

for (var i:uint = 0; i <= stage.stageWidth; i++) {
	var amplitude:Number = Math.sin(frequency * Math.PI*2 * i/stage.stageWidth);
	graphics.lineTo(i, axisY - amplitude*amplitudeMultiplier);
}

But... I want to draw a exponential sine wave, like this:



I think the Math.exp()-function can be useful. Please, help!

Thanks already!

[rynoe]

some dude made this one.

[akirasada1972]

You mean this kind?
Add this code at the end.
I hope this works like you think.

frequency=frequency+frequency/1000;

[swak]

There are two approaches you can take. Either adjust the frequency directly in the loop or take into account the i:
This one basically adjusts the frequency based upon the x position.

for (var i:uint = 0; i <= stage.stageWidth; i++) {
	var amplitude:Number = Math.sin((frequency+i/10) * Math.PI*2 * i/stage.stageWidth);
	graphics.lineTo(i, axisY - amplitude*amplitudeMultiplier);
}

This basically keeps increasing the frequency based upon the number of loops run.

for (var i:uint = 0; i <= stage.stageWidth; i++) {
	var amplitude:Number = Math.sin(frequency * Math.PI*2 * i/stage.stageWidth);
	frequency+=frequency/100;
	graphics.lineTo(i, axisY - amplitude*amplitudeMultiplier);
}

Either one will work but the one based upon x position would probably be simpler in some ways.