Sit down at a Starlink terminal, and type:
You’ll get a little “hello” message, and a new prompt:
Type
hit the return key. You will get an error message. Ignore this and read on. Type
and hit return. You have just completed your first DIPSO session, discovering on the way that DIPSO accepts more than one command on a line (each command being separated by commas), that upper- and lower-case inputs are accepted, and that DIPSO knows when you make mistakes (or at least, some kinds of mistake).
You didn’t do much, though; you’ll need to know a few more commands. A full reference list of
commands (ordered more or less alphabetically) is appended, but here we’ll mention a
few basic ones to get you going. (You should check the command descriptions for details
of how they should be used.) Once in the program, you can use the COMM command to
get lists of commands classified by function together with brief descriptions (for instance
“COMMANDS g” will list all the graphics-related commands), or use HELP for more detailed
information on individual commands. Data can be read in using the READ command, or in special
cases one of the following commands: ALASRD, SCREENRD, SP0RD, SP1RD, SP2RD, ATLASRD, or
RESTORE.
For “historical reasons” many people use the “Spectrum 0” format for input and output of data
(SP0RD, SP0WR). However, the recommended file i/o commands are READ and WRITE (or SAVE
and RESTORE), which preserve all the information which DIPSO associates with a data
set.
To get a plotting surface, use the DEV command. Plotting is usually done with PM; unless you’ve
provided X and Y ranges (with XR and YR, or some combination of XMAX, XMIN, YMAX, and YMIN) the plot
is auto-scaled to the minimum and maximum values in the arrays.
Once you have managed to read in some data, and plot them, you will soon want to carry out
measurements, change the style of the plots, and so on. To find out how to proceed, you should read
the descriptions of commands like (HIST, POLY, MARK); (XV, YV, XYV); (CSET, CROT); and (TPORT,
TZONE).
Type q to leave the program. If in the middle of something long and tedious you despair, you can type
control-C; this stops execution of the current command, and returns you to the DIPSO command
prompt.
If you decide in the middle of a DIPSO session that you need to issue some operating system
commands, then simply push the DIPSO task into the background by typing control-Z, issue your
operating system commands, and then re-enter DIPSO by typing fg.