Need implementation of algorithm savitzky-golay in Swift 4

A Savitzky–Golay filter is a digital filter that can be applied to a set of digital data points for the purpose of smoothing the data, that is, to increase the precision of the data without distorting the signal tendency. This is achieved, in a process known as convolution, by fitting successive sub-sets of adjacent data points with a low-degree polynomial by the method of linear least squares. When the data points are equally spaced, an analytical solution to the least-squares equations can be found, in the form of a single set of "convolution coefficients" that can be applied to all data sub-sets, to give estimates of the smoothed signal, (or derivatives of the smoothed signal) at the central point of each sub-set. I need the implementation of a 3rd order savitzky-golay filter in Swift. func smoothRadios(radios:[(frame: Int, radio: Double)])->[(frame: Int, radio: Double)] Where frame is the X axis and radio is de y axis. No milestone is payed in advance. Please dont insist.