Normalise a CIVector - ideal for use as a convolution matrix

gistfile1.txt

extension CIVector
{
    func normalize() -> CIVector
    {
        var sum: CGFloat = 0
        
        for i in 0 ..< self.count
        {
            sum += self.valueAtIndex(i)
        }
        
        if sum == 0
        {
            return self
        }
        
        var normalizedValues = [CGFloat]()
        
        for i in 0 ..< self.count
        {
            normalizedValues.append(self.valueAtIndex(i) / sum)
        }
        
        return CIVector(values: normalizedValues,
            count: normalizedValues.count)
    }
}