A reference variable having a linear relationship with the angular position of a master axis is set, and a correspondence between this reference variable and the displacement of a slave axis is stored in a data table. One execution stage is specified by setting a starting reference variable and an ending reference variable from this data table. A desired sequence is assigned to a plurality of execution stages thus specified. The reference variable corresponding to the angular position of the master axis is determined, slave axis displacement data corresponding to the reference variable is read out, and the slave axis is positioned in accordance with the position of the master axis on the basis of this displacement data.