| 52 | | === Introduction === |
| 53 | | |
| 54 | | DVO (the Desktop Virtual Observatory) is a system for manipulating collections of images and measurements related to astronomical objects. The DVO system consists of several programs which insert data in the database system, extract data from the database, or manipulate data in the database. One of these is the DVO shell, which provides a command-line driven, programmable user interface to the astronomical objects and measurements in the database. The DVO shell is based on the [wiki:Opihi_Shell_Language Opihi shell language] which provides the tools to manipulate and display data in various representations. The DVO shell adds to this basic command set a collection of functions which provide direct access to the contents of the DVO database tables. |
| 55 | | |
| 56 | | === Schema === |
| 57 | | |
| 58 | | DVO uses the following database tables: |
| 59 | | |
| 60 | | * Sky Layout : defines the organization of the object / measurement tables on the sky |
| 61 | | * Photcodes : defines the photometric systems and transformations between them |
| 62 | | * Images : describes the images known the DVO; for a mosaic camera, one chip corresponds to a single image, and an additional meta-image is used to represent the full mosaic (note: these meta-images may soon be moved to a separate table; also note that the mosaic meta-image is only supplied for mosaic images with 'mosaic' astrometry solutions). |
| 63 | | * Average : average properties of the astronomical objects, excluding photometric average information (one row per object) |
| 64 | | * SecFilt : average photometric properties for astronomical objects (one row per 'average' filter per object). |
| 65 | | * Measure : all detections of the astronomical objects |
| 66 | | * Missing : non-detections of known astronomical objects nominally touched by an image (note : this table is not populated by default) |
| 67 | | |
| 68 | | The standard implementation of DVO uses a stores the database information as a collection FITS tables. For a subset of the tables (Average, SecFilt, Measure, Missing), the data is partitioned into multiple files representing different regions on the sky. The partitioning scheme allows for a wide range of scale on which the sky is divided. At one extreme, the entire sky is represented by a single file. At the next level, this is split into Declination bands of width 7.5 degrees. Next, these bands are split into RA ranges. The next levels subdivide the RA / DEC ranges into smaller and smaller patches. From the third level on down, the size of the sky regions varies with Galactic latitude to better sample regions of high and low stellar density. |
| 69 | | |
| 70 | | === DVO Shell === |
| 71 | | |
| 72 | | * [wiki:Opihi_Shell_Language Opihi Shell Language] |
| 73 | | * [wiki:DVO_Command_Help_Pages DVO Command Help Pages] |
| 74 | | |
| 75 | | === Working With DVO === |
| 76 | | |
| 77 | | * Inserting Data (addstar) |
| 78 | | * [https://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/attachment/wiki/IPP_Description/dvo_extract_keywords.txt DVO Keywords] : A partially-completed list of keywords that can be used with "mextract" and "avextract" |
| 79 | | * [https://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/attachment/wiki/IPP_Description/ex_cmd.dsc Example CMD Script] : An example DVO script that produces a color-magnitude diagram |
| 80 | | * [https://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/attachment/wiki/IPP_Description/ex_hist.dsc Example Histogram Script] : An example DVO script that produces a histogram |
| 81 | | |
| 82 | | === Other DVO Pages === |
| 83 | | |
| 84 | | * [https://svn.pan-starrs.ifa.hawaii.edu/trac/ipp/attachment/wiki/IPP_Description/DVO_workshop.ppt DVO MPIA Workshop] : Powerpoint slides covering some of the basics of using DVO |
| 85 | | * [wiki:DVO_FAQ DVO FAQ] -- look here for questions and solutions and add your own! |
| 86 | | * [http://kiawe.ifa.hawaii.edu/Elixir/Ohana/DVO/ DVO Intro] : introduction to the Desktop Virtual Observatory (on the CFHT elixir pages) |
| 87 | | * [http://pan-starrs.ifa.hawaii.edu/project/IPP/documentation/dvo.pdf dvo.pdf] manual from project documentation pages (needs updating, but describes concepts of dvo) |
| 88 | | * [wiki:DVODB.Synth.grizy.bright DVO DB Synth grizy bright] -- Bright-end subset DVO database with complete Ohana tarball |
| 89 | | * [wiki:DVO_Example DVO Example] -- a tarball and instructions on very basic DVO usage |
| 90 | | * [wiki:DVO_Challenge DVO Challenge] -- links to notes and Heidelberg slides created by Mike Liu |
| 91 | | * [wiki:DVO_Challenge#FAQ_/_Suggestions_for_Changes Includes FAQs and change suggestions] |
| 92 | | * [wiki:Dvo_tutorial DVO tutorial] -- attempt at a cookbook-style tutorial started by Sebastian Jester |
| 93 | | * [wiki:USNO-B_in_DVO USNO-B in DVO] : Building the USNO-B DVO catalog |
| 94 | | * [wiki:2MASS,_USNO-B,_SDSS_Merge 2MASS, USNO-B, SDSS Merge] : Notes on generating a merged DVO database |
| 95 | | * [wiki:2MASS_info_in_DVO 2MASS info in DVO] : A quick summary on what info from 2MASS has been imported into DVO |
| 96 | | * [wiki:DVO_GPC1_pt_2 DVO GPC1 pt 2] : MWV's test of DVO and addstar with GPC1 pt 2 release (see mail to ps-ipp-users from Gene Magnier on 2008/10/06) |
| 97 | | |
| 98 | | * '''SDSS stripe82 data set''' For the daring, here is a 202 MB tarfile expanding into a 588 MB directory with a very small subset of multi-epoch (but not [yet] coadded) SDSS stripe 82 data at [http://www.mpia.de/homes/jester/IPPstripe82_catdir_20080610.tgz http://www.mpia.de/homes/jester/IPPstripe82_catdir_20080610.tgz] The README describes what's there and how it was made. This is not (yet) useful for science! Email jester at mpia.de with questions regarding this dataset. |
| 99 | | |
