== DVO Example using the Simtest reference database ==
(Up to [wiki:DVO_TopLevel DVO Top Level]) 

This example uses the simtest reference database (catdir.grizy.simtest).  The ptolemy.rc file attached to this page may also be useful.

* download the database from {{{rsync://ipp0222.ifa.hawaii.edu/ippRefs-synth.simtest}}}

* Display the area covered by the database:

{{{
catdir catdir.synth.simtest/
resize 1000 500
region 180 0 90 ait
cgrid -c red; skycat
}}}


* Zoom in on an area with data:
{{{
region 151 3.5 3.0
box
skycat -c red -lw 2
pmeasure -all -m 10 15 -pt 7
label -x "ra offset" -y "dec offset" +x "region 151 3.5 3.0"
png -name sample.region.large.png
}}}
[[Image(sample.region.large.png)]]

* Zoom in on a smaller region
{{{
region 151 3.5 0.25
box
pmeasure -all -m 10 15 -pt 7
label +x "region 151 3.5 0.25"
png -name sample.region.small.png
}}}
[[Image(sample.region.small.png)]]

* Make a color-color diagram (average magnitudes)
{{{
avextract -region ra, dec, objid, g_SYNTH, r_SYNTH, i_SYNTH, z_SYNTH, y_SYNTH
set gr = g_SYNTH - r_SYNTH
set ri = r_SYNTH - i_SYNTH
lim -n 1 gr ri; clear; box; plot gr ri
label -x "g - r" -y "r - i"
png -name sample.cmd.png
}}}
[[Image(sample.cmd.png)]]

* Extracting data on a specific object (three methods):
{{{
gstar -m ra[0] dec[0] 0.001
gstar -m ra[0] dec[0] 0.001 -full
mextract -region RA, DEC, MAG, TIME where ((abs(RA - ra[0]) < 0.001) && (abs(DEC - dec[0]) < 0.001))
}}}