Calculates the first derivative of signal data
sfaTimediff(DATA, axType = "ORD1")
The matrix of signals for which the derivative is calculated (one column per signal)
Type of interpolation: "ORD1" (default) first order, "SCD" second ,"TRD" third, "ORD3a" cubic polynom
DATA contains the derivative signals, with the same structure as the input data.
setting axType to invalid values will lead to first order interpolation.