This command has two basic modes of operation. In default mode it sets the current position either by cursor or parameter, depending on the current system mode. In keyboard mode the position may be specified in a number of specified coordinate frames.
Alternatively, by use of command line switches it can be made to
manipulate lists of RA/DEC positions. The keyword 'ENTER' will
put it into entry mode, in which a list of positions may be
entered in one of three ways: positions may be entered at the
keyboard with ' ', '-' or '\' indicating continuation; a text
file of positions may be entered; or a PSS results file may be
given. Positions currently held in the system may be listed
using the 'SHOW' keyword, and a position may be selected from
the list to be the current position by using the 'SEL' keyword.
If entering RA/DEC see the section in 'User_interface' which explains the formats that may be used.