Repetitive Analog Computer for Analysis of Sums of Distribution Functions

Many experimental procedures yield curves which are sums of distribution functions. Examples of such curves include electrophoretic, diffusion, and ultracentrifugal patterns, absorption spectra, and curves from countercurrent distribution and from partition chromatography in either liquid or vapor phase. In a given type of curve, each of the component functions is identical to the others in form (for example Gaussian) but can have very different values of the parameters governing height, width, and position along the abscissa. We wish to determine the parameters for each component by an analysis of the sum curve. The computer to be described performs this analysis by synthesizing a number of distribution functions of the desired form, each with adjustable parameters, and presenting, on an oscilloscope, the sum of these functions for comparison with the experimental curve being analyzed. A match is made visually by adjustment of the various parameters. When a match has been obtained, the parameters of the component functions are read out, following a switching procedure which presents the individual functions in sequence.