Designs a Savitzky-Golay FIR smoothing filter, returning the designed Savitzky-Golay filter coefficients and the differentiation filter coefficients.
The number of data points to each side of the current data point to use for the least-squares minimization.
side points*2 + 1 is the length of the moving window, which must be greater than the polynomial order.
Order of the polynomial.
Weighting vector to use in the least squares minimization.
This array must be empty or have a length of side points*2 + 1.
Error conditions that occur before this node runs. The node responds to this input according to standard error behavior.
Default: No error
A matrix with rows representing the FIR filter coefficients.
The matrix is n-by-n, where n is side points*2+1.
A matrix where the p-th row is the differentiation filter for the p-th order derivative.
The matrix is m-by-n, where m is polynomial order+1, and n is side points*2+1.
This node computes differentiation filters only if compute differentiation filters? is True.
Error information. The node produces this output according to standard error behavior.
The Savitzky-Golay filter smoothes a noisy signal by the piece-by-piece fitting of a polynomial function to the signal. This node performs the fitting by least squares minimization. The length of the moving polynomial fitting window is 2k+1, where k is side points.
The central row of Savitzky-Golay filters estimates the middle point of the moving window. The other rows of Savitzky-Golay filters smooth the endpoints of the signal, where the window length exceeds the number of remaining data points.
To smooth a signal, apply the first k rows of Savitzky-Golay filters to the first 2k+1 points of the signal to get the first k smoothed points. Apply the last k rows of Savitzky-Golay filters to the last 2k+1 points of the signal to get the last k smoothed points. Apply the central row of Savitzky-Golay filters for all other points.
Where This Node Can Run:
Desktop OS: Windows
FPGA: Not supported