Numerical integration of differential equations on the 704 EDPM

To provide a convenient means for solving complex and nonlinear ordinary differential equations, a system has been devised which causes a 704 EDPM to behave like an analogue differential analyzer. Use of this system involves the interconnection of appropriate subroutines in a manner analogous to the interconnection of operational amplifiers in an analogue machine. The subroutines are designed so that the user may compile the required connections automatically, without much knowledge of digital computer coding. Solving differential equations by this method takes no more setup time than that required by analogue machines and in many cases may be a good deal faster. Integration is done by using Milne's formulas. The system automatically adjusts the integration interval to take advantage of portions of the solution which can be computed with large intervals at no sacrifice of accuracy. Nonlinear functions may be expressed by a table of values in storage.