MINIATURE DIGITAL COMPUTER CIRCUIT FOR DETERMINING VALUES OF COMBINED VARYING QUANTITIES

A miniature digital computer circuit capable of operating in substantially instantaneous real time for determining values of combined varying quantities. The circuit has inputs for two variable digital pulse trains. A decoder and shift register compress bit groups to minimize sizes and operating times of associated digital pulse readout memories, multipliers and adders. The circuit adds to combined functions of the varying quantities the sum of significant terms from a differential expansion of the function, to obtain readouts representing changes in the functions.