Here are a few more functions useful in creating CGRect’s from a center point and size.
Example usage:
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  | view.frame = CGRectWithCenterWidthHeight(parent.center,30,30); 
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Full set of functions
interface  
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  | CGRect CGRectWithCenterAndSize(CGPoint center, CGSize size); CGRect CGRectWithCenterWidthHeight(CGPoint center, CGFloat width,CGFloat height); 
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implementation  
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  | CGRect CGRectWithCenterAndSize(CGPoint center, CGSize size){     return CGRectMake(center.x - (size.width/2), center.y - (size.height/2), size.width, size.height); } CGRect CGRectWithCenterWidthHeight(CGPoint center, CGFloat width,CGFloat height){     return CGRectWithCenterAndSize(center,CGSizeMake(width, height)); } 
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