A XY-plotter is placed in the Computer Center of Shimane University, but it is not used too much.
In this paper the application programs are described which were developed to heighten the utility value of the XY-piotter. On the occasion of developing, we wanted to make full use of the system subroutines made by the maker. So a reverse assembler was produced and their system subroutines were interpreted.
The developed programs are as follows :
(1) the subroutine which automatically draws a graph on the orthogonal co-ordinates without considering at all the values for data.
(2) the group of subroutines which draws a graph on the logarithmic co-ordinates.