HAS-Motion Software Documentation

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| |second_derivative.png\\ \\ **second_derivative**| | |**/signal_types=** |the type of signal to be processed | |**/signal_names=** |the names of the signals to be processed| |**/signal_folder=** |the name of the signal folder | compute the second derivative at each point of a signal. the first and last data points become data_not_found(identified in the c3d file as a point reliability value of &endash;1). derivatives are calculated using finite difference algorithms. given the signal: x(ti) for i=1, 2, ..., n the second derivative is calculated using: xddot(ti)= (x(ti+1)-2x(ti)+x(ti-1))/( (ti+1)-(ti) )^2