Here a few functions that are handy for the analysis of kinematic data.

List of functions

1. Calculating numerical derivatives and smoothing
velocity_discr Numerical first derivative (with filter option)
acceleration_discr Numerical second derivative (with filter option)
tangvelocity Tangential and vector velocity
smooth_kernel Gaussian kernel smoothing (1-dim)
2. Landmarking, cutting and stretching
findstart Finds start of movement, excludes false starts
findend Finds end of movement, including/excluding submovement
cut Cuts out a kinematic trajectory for placement in matrix
lengthstandard Stretches kinematic data to a certain length

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