Hi John,
Apologies for not saying "thanks" earlier but I've now got the tdf
working in a form that suits me (although it is a rather tedious
process as you say).
Trouble has been we had quite a few clear nights just as I fixed the
tdf and then I was away for a few days.
Anyway, thought I should inform you you're efforts have been
appreciated. (Ditto the latest novae in Cyg).
Cheers,
Roger

----- Original Message -----
From: "duble.stars" <duble.stars@...>
To: <guide-user@yahoogroups.com>
Sent: Friday, March 09, 2007 7:16 PM
Subject: [guide-user] SDSS in Guide - the alternative route
(pronounced root)


>
>
> Hiya again Roger
>
> Evidently you'd like to plot SDSS stuff in Guide, and there is an
> alternative way of doing it, but it's a bit mulish.
>
> Some data has to be processed a bit, and I do that with a little
> qbasic proggie, however it can be done in Excel, and I vaguely
> remember sending Mike Simonsen a minitutorial on how to do that some
> ages ago.
>
> Basically Guide TDF commands of the following nature
>
> ~r 4 6 do this that,
> ~b 8 10 and the other
>
> are of a syntax such that the first number is the _start_ column
> number of a field of data on a line, and the second number is the
> length of the field, the total number of columns, so for instance
with
> data of this nature
>
> object1 17.5 22.6994 5.6
> object2 22.8 01.4255 1.0
>
> to display the second set of figures would mean writing
>
> ~b 9 4 %s\n
>
> ie display in Both help and more info the value (returned by the %s
> symbol) shown starting at column 9 and of length 4 columns, then
start
> a new line (that's what the \n does).
>
> So ~b 9 4 %s\n would return 17.5 for object1, and 22.8 for
object2.
>
> Anyway, back to da sdss.
>
>
http://cas.sdss.org/dr5/en/tools/search/x_radial.asp?ra=RDEG&dec=DDEG&
radius=9&entries=all&format=csv
>
> is the basic url for fetching SDSS data. RDEG is replaced by any
> value in decimal degrees, as is DDEG, within the sdss coverage.
>
> So
>
>
http://cas.sdss.org/dr5/en/tools/search/x_radial.asp?ra=120.4&dec=+37.
8&radius=9&entries=all&format=csv
>
> returns data centred on RA 120.4 degrees declination +37.8 degrees,
> for a radius (&radius=) of 9 arcminutes in this instance.
>
> You type that into your browser, it all goes away to sdss, and after
a
> while your browser tells you that you have a file called
>
> results.csv
>
> to download.
>
> This is a comma delimited file, with the first line as a header line
> telling what the columns are, you save that to disk and the load it
> into excel.
>
> Now, here's the TDF that this will need converting for :-
>
> file SDSS.dat
> title SDSS dr5
> RA H 3 9
> units0 -2 # RA 'hours' are really decimal degrees
> de d 13 9
> mag 37 6
> text 94 13
> ~c 1 1 SDSS dr5
> ~c 1 0 0 unknown\n
> ~c 1 0 1 cosmic ray\n
> ~c 1 0 3 galaxy\n
> ~c 1 0 4 ghost\n
> ~c 1 0 6 star\n
> ~r 3 9 RA 2000 %R\n
> ~r 13 9 Dec2000 %D\n\n
> ~b 23 6 u' %s
> ~b 58 6 err %s\n
> ~b 30 6 g' %s
> ~b 65 6 err %s\n
> ~b 37 6 r' %s
> ~b 72 6 err %s\n
> ~b 44 6 i' %s
> ~b 79 6 err %s\n
> ~b 51 6 z' %s
> ~b 86 6 err %s\n
> ~b 94 5 V %s B-V
> ~b101 5 %s\n
> ~r 1 1
>
\n^DATA//xhttp://cas.sdss.org/dr5/en/tools/explore/obj.asp?ra=%[3,9]&d
ec=%[13,9]^\n
>
> epoch 2000
> type 6
> field 0.00 2.00
> mag lim 60
> shown 7
> end
>
> (The line starting ~r 1 1 followed by another line starting
\n^DATA
> is all one line that'll have been wordwrapped, fix it so it starts
>
> ~r 1 1 \n^DATA//xhttp://cas.sdss. and carries on to the
end).
>
> So, you have to convert the comma delimited file such that this sdss
> tdf file will work with it.
>
> Load results.csv into excel and change it as per the TDF, ie the RA
> has to start at column 3 and be 9 columns long. This is standard
> excel column widening and shortening practice, you may need to
change
> the number of decimals displayed too.
>
> You may be able to use record macro for this, not sure, but if so,
> then once you've done it once it's just a matter of invoking the
macro
> on future occasions.
>
> When it's all lined up properly to fit the TDF, save it as a .prn
> file, ie space delimited.
>
> It's likely that a coupla columns from the input data need to be
> deleted, as you only need stuff like the mag etc.
>
> The SDSSdr5.tdf data file is called sdss.dat and needs to live in
the
> guide directory, using a text editor you append the new .prn files
to
> the main sdss.dat file... ...yeah, I know, tedious.
>
> But it works, and after a while you'll have quite a few SDSS fields,
> I'm guessing for CVs in your case, all there ready.
>
> Oh, I've missed a bit, the V and B-V entries are added by adding
> columns in Excel using the formulae
>
> V = r' + 0.44*(g'-r') - 0.02
>
> good to about +/- 0.05 V
>
> and
>
> B-V = 1.04*(g'-r') + 0.19
>
> good to about +/- 0.1 B-V (which is a bit ropy actually, but just
> about usable).
>
> However, as these are the last values in the tdf it does not matter
if
> they are not generated, if they aren't there they'll simply not be
> displayed.
>
> Someone who knew what they were doing could likely compile a bit of
C
> or perl or something that'd take as input RA and Dec and radius, go
to
> sdss, fetch the comma delimited data, expand it out to space
delimited
> that fits the above tdf column discipline, and even autogenerate the
> arithmetically derived V and B-V, and append it to the sdss.dat
file.
>
> I kind of do that with qbasic, but that's archaic, and don't work
all
> that cleanly, needing a coupla stages (the data has to be converted
> from unix to dos line ending protocol for a start else qbasic thinks
> it's all just one very long line) and few folk know how to run dos
off
> their PCs nowadays, let alone have access to qbasic.
>
> It's mulish, but it works, until SDSS became available in VizieR
> that's how I did it, and still do sometimes, because the above route
> uses full SDSS data release 5, whereas VizieR has only just upgraded
> to SDSS data release 4.
>
> Cheers
>
> John
>
> --- In guide-user@yahoogroups.com, "Roger Pickard" <rdp@...> wrote:
> >
> > Hi John,
> > Well thanks for your kind efforts but . . . .
> > I run UCAC2 from the hard drive so don't even have the toolbar for
it
> > at all. But . . . . .
> > It still doesn't work even with the new s come gsc22 .exe so it
must
> > be something Bill has done.
> > Oh well, interesting exorcise and at least I've learnt a tiny bit
more
> > about these things.
> > Cheers,
> > Roger
>
>
>
>
> ------------------------ Yahoo! Groups
Sponsor --------------------~-->
> Yahoo! Groups gets a make over. See the new email design.
> http://us.click.yahoo.com/hOt0.A/lOaOAA/yQLSAA/1.XolB/TM
> --------------------------------------------------------------------
~->
>
> To unsubscribe from this group, send an empty email to:
> guide-user-unsubscribe@egroups.com
> Yahoo! Groups Links
>
>
>
>
>