PURPOSE: To generate a business form by a simple operation by reading out the corresponding isolation data from a storage device at the time when an isolation object apparatus from in a displayed system diagram is selected by a coordinate instructing device, and generating the business form and the system diagram for isolation.

CONSTITUTION: When a prescribed position on a selection screen displayed on a CRT device 2 is instructed by a mouse, a CPU 3 reads out a system diagram corresponding to its position from a disk device 4 and displays it. Subsequently, when a position of an isolation object apparatus on the screen is instructed by the mouse 1, the CPU 3 reads out an attribute of a specific isolation object apparatus in its position from the disk device 4, generates a business form by using this attribute as isolation data, generates a system diagram for isolation from the isolation data and the original system diagram and saves it in the disk device 4. Next, when its output is instructed by the mouse 1, etc., it is outputted to a printer 5. In such a way, by only designating the isolation object apparatus in the displayed system diagram, a business form of a prescribed format is generated automatically.