1. An electronic drawing generation apparatus that generates an electronic drawing given to an electromagnetic field simulator for analyzing an electric field and a magnetic field of a substrate where a circuit is formed based on the electronic drawing, the apparatus comprising: a shape determination device that determines a necessary part in the substrate, the necessary part needing to be subjected to simulation by the electromagnetic field simulator; a shape edit device that cuts out the necessary part determined by the shape determination device; a storage storing a design rule database that includes design rules; and a storage storing an analysis technique database that includes a list of analysis techniques complying with the electromagnetic field simulator, wherein the shape determination device includes a design rule check section that determines a design-rule violating part as the necessary part, the design-rule violating part being a part violating the design rules included in the design rule database, and a necessary shape determination section that determines the necessary part based on the design-rule violating part and the analysis techniques included in the analysis technique database.