XYPS controls the position of the centre of the VIEW on its owning Sheet. The attribute takes two numeric values, which are the coordinates of the centre of the VIEW relative to the bottom left corner of the Sheet. The attribute can be set directly by commands, for example,

ONPOS is the position of the centre of the VIEW contents, relative to the centre of the VIEW. VIEW contents are centred within the VIEW by default, so this attribute takes the default values x0 y0. ONPOS is set directly, for example: