Conrad's DVO Worksheet

Introduction

The purpose of this page is to develop and introduction to using DVO from the complete perspective of a new non-astronomer user.

Logging into IPP and starting DV0

  • Step 1) You need to do is log into an IPP machine that runs DVO. Example below:
$ssh -X -p 9005 ipp5u

Note: There is an X windows session and the port is 9005 and the machine ipp5u is only accessible internally to the cluster. If you need to ssh from an outside machine, see sshing.

  • Step 2) Setup your psconfig to setup your ps lib configuration. Example below
    $psconfig --list
    PSCONFDIR : /home/panstarrs/ipp/psconfig
      Archives   : Archives
      lin64      : ipp-20120216
      lin64      : ipp-20120404
      lin64      : ipp-20120531-debug
      lin64      : ipp-20120531
      lin64      : ipp-eam
      lin64      : ipp-trunk
      bash       : psconfig
      csh        : psconfig
    $psconfig ipp-20120531
    
  • Step 3) Launch DVO
    $dvo
    

Getting Started with DVO

If you have successfully launched dvo you will be see the dvo prompt. Several useful commands:

  • ?? - Gives all the system environment variables available (i.e., HOME, PID, etc).
  • ? - Shows all the available dvo commands .
  • ! - Gives the ability to execute systems commands. Example:
    dvo: ! echo "Hello World"
    Hello World
    
  • vectors - Tells you what variable vectors you have loaded into memory.
  • help command - Gives specific information on the given command (if available). Examples:
    dvo: help imextract
    No help for: imextract
    dvo: help skyregion
    No help for: skyregion
    dvo: help tv
    
      tv [-log] (buffer) [zero range]
    
      display an image in the Ki'i window (X display program).  zero and
      range specify the data values corresponding to the color mapping.
      If they are not specified, the old values are used (default is 0,
      1024).
    
      If -log is specified the color mapping scale will be logarithmic.  
    
    
      See Also: Kii, rd, cursor
    
    

also try

dvo: imextract --help

To list specifics fields of a table:

mextract --help fields
avextract --help fields

More commands

catdir /data/ipp005.0/gpc1/catdirs/SAS/20120510/


vectors

 echo RA[0]

writing to files

 write conrad.dat RA DEC -csv

Case Study: Trying to query for stacks with inaccurate data

Background

After doing some queries into PSPS, one particular query for data quality is to find instrumental flux values that are equal to zero. This should not be possible but some small amount of entries were found.

Steps to trace inaccurate data from PSPS to IPP

  1. Find the inaccurate data within PSPS.
    SELECT objID,
           stackDetectID,
           ippObjID,
           ippDetectID,
           ra, dec
           filterID,
           instFlux,
           calMag,
           instFluxErr,
           calMagErr
      INTO mydb.weird_stacks FROM StackDetectionFull
     WHERE (instFlux <> -999 AND instFlux <= 0 )
    

Example result set:

objID stackDetectID ippObjID ippDetectID ra dec filterID instFlux calMag instFluxErr calMagErr
114493301340728546 1647540050000036013 18833000017688 3601 330.134073398733 5.41507490193458 3 0 22.3856067657471 0 0
114503301083933978 1647540050000038753 18833000017804 3875 330.10839364124 5.41959990782918 3 0 22.3856067657471 -999 0
114503301227007106 1647540050000037023 18833000017719 3702 330.122691648098 5.42220775996642 3 0 22.3856067657471 0 0
114493301366688211 1647540050000035773 18833000012460 3577 330.136649626611 5.4148051915739 3 0 22.3856067657471 0 0
114503301089985901 1647540050000038693 18833000012717 3869 330.108989815023 5.42121110126328 3 0 22.3856067657471 -999 0
114503301439643873 1647540050000034893 18833000017626 3489 330.143945982482 5.41951876040932 3 0 22.3856067657471 0 0
114493301427446802 1647540050000035093 18833000017644 3509 330.142760240845 5.41363441590307 3 0 22.3856067657471 0 0
114503301102937321 1647540050000038563 18833000017782 3856 330.110293316183 5.4223861344834 3 0 22.3856067657471 -999 0
114493301431512878 1647540050000035033 18833000012411 3503 330.143162673458 5.41034250994028 3 0 22.3856067657471 0 0
114503301103546828 1647540050000038543 18833000017783 3854 330.110331520645 5.42194339501451 3 0 22.3856067657471 -999 0
  1. Find out the dvo path that the IPPTOPSPS is getting its data from. See dvo_location variable IPPTOPSPS Config table.
  1. Run dvo and set the catdir from the dvo prompt.
    dvo: catdir /data/ipp005.0/gpc1/catdirs/sas/20120510
    
  1. Set the region so that its roughly within the same area of the above stacks. region Ra Dec Radius [projection] [orientation]
      region 330.134073398733 5.41507490193458 0.1
    
  1. Load a vector from that sky region and observe it.
    mextract RA, DEC, photocode, mag, mag:err, objID, detID, catID
    vectors
    
  1. Write the vector to a dat file
    write /tmp/bad_stacks.dat RA, DEC, photocode, mag, mag:err, objID, detID, catID
    
  1. This gets fuzzy. Obtain the FITS file related to the Dat file. The reason for doing this is that the SVO does not store the instflux value that we are looking for.
    • Log into the gpc1 database to option the externID which is a subset of the last four digits of a IPPObjID ?
    • from here you query to get to the stackID and the SkyID
    • From the SkyID you get the path to the FITS file that you want from I believe the static sky table.
    • Search for the matching stackID to find the entry you want and view the instFlux value.