How to make a sprite rotate to a touch Cocos2d

I have an arrow sprite, and it is for aiming purposes in my Cocos2d game. Therefore, I want it to point to w开发者_开发问答here the user touches the screen. How do I program the rotation of the sprite so it will rotate to the user's touch location? Thanks!

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These tutorials may be helpful:

http://www.learn-cocos2d.com/knowledge-base/cocos2d-iphone-faq/learn-cocos2d-public-content/manual/cocos2d-general/14826-how-to-rotate-a-sprite-in-a-circular-motion/

http://www.raywenderlich.com/2343/how-to-drag-and-drop-sprites-with-cocos2d

Also, this question is asked (with code) and answered (with more code) here: Rotating Sprite with Touch - Cocos2d

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I haven't actually done this before, but I have adapted some of my code (that makes a enemy ship face the player ship) to what you need. Hopefully this is correct.

//rotate to face the touch
CGPoint diff = ccpSub(sprite.position, touch.position);
float angleRadians = atanf((float)diff.y / (float)diff.x);

float angleOffset = CC_DEGREES_TO_RADIANS(90);

if(diff.x < 0)
{
    angleRadians += angleOffset;
}
else
{
    angleRadians -= angleOffset;
}

PengOne's answer (cool name BTW) was great though and I am voting it up because you should make use of it.