Previous page  Page 68   Next page    Table of Contents 

you click for more info.

   Because "Color index" is in carets (^),  Guide will show that text
highlighted;  when you click on it,  you'll get a glossary definition.

   Some datasets store data as special flags.  For example, in the
quasar data,  column 22 can contain an "A",  "O", "R",  or just a blank
space. Each flag has a meaning.  The following lines in the .TDF file
translate:

~d~~r 22 0 A Position is of low accuracy\n
~d~~r 22 0 O Position was found optically,  and is good to 1" or better\n
~d~~r 22 0 R Position was found by radio,  and is good to 1" or better\n

   As it stands,  nothing is shown if column 22 is blank,  but using

~~r 22 0   Position is not of low accuracy\n

   (or something similar) would fix that problem.

20d: Adding note files for .TDF datasets        

   It is also possible to add note files for a .TDF dataset. There is
only one example available,  for the Binary Star data (BINORBIT.DAT),
the last dataset defined in CD_DATA.TDF.

   You'll notice that the format description for BINORBIT contains this
line:

~~n  2  15 binorbit.not

   In plain language,  this means "Notes for this dataset are found in
the file BINORBIT.NOT,  and are indexed using the fifteen characters
found starting at byte #2 in lines from BINORBIT.DAT."

   This example was chosen because the binary orbit dataset already
provided notes for most of the stars,  indexed by their RA/dec values
(which are given in BINORBIT.DAT in columns 2-16).  You will see that
the .NOT file itself is of the sort common in Guide:  the object is
specified with a tilde (~~)  plus the object identifier,  and then
text is given for that object.

21: Adding your own notes for objects     

   Not many people will have a need to add their own datasets, except
for some special-purpose projects.  A more common wish is to add some
comments for an object.  If you know how to use a text editor,  this is
quite simple to do.

   For example,  let's say that you have just observed NGC 253,  and
would like to make some notes on what you saw. Go to your text editor,

 Previous page  Page 68   Next page    Table of Contents