The

slope finder program determines clathrin coat growth rate distributions from intensity traces. It takes as an argument the cell array of intensity value output by

TraCKer, the frame rate of the movie, and a global background value for the movie (i.e. the value of a signal with SNR=1). The output of this function is the slope of the intensity values after they have been normalized to the maximum intensity of that trace. The output is a cell array where each cell is the same length as the corresponding intensity cell. Since it is impossible to apply a consistent slope finding algorithm to the endpoints of the data, they are padded with zeros, so to form a proper slope histogram all zeros should be excluded.