sep 6, 20082008 nvo summer school1 using iraf in the vo mike fitzpatrick, noao t he us n ational v...
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Sep 6, 2008 2008 NVO Summer School 1
Using IRAF in the VO
Mike Fitzpatrick, NOAO
THE US NATIONAL VIRTUAL OBSERVATORY
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: NVO Package
Strategies:
• Build upon VOClient• Support scripting and compiled task development• Provide low-level toolbox utilities that enable higher-level script
task development– Let the user decide how to build the application best suited
to them
• Provide high-level demonstration science applications (scripts)– People learn from examples – Can easily modify to get slightly different behavior
• Simplify interfaces as much as possible– Don’t require detailed knowledge of VO protocols to use the data
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: NVO Package
High-Level Applications - Common Features
• Uses local image footprint for query
• Object name resolved to position (plus search size)
• Arbitrary RA/DEC position (plus search size)
• Query in alternate coordinate systems (e.g. ecliptic, galactic)
– VO standard is (non-intuitive) decimal degrees
– Leverage IRAF capabilities to transform coords
• Tables output as ASCII text (others available)
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: NVO Package
Low-Level (Toolbox) Applications
• Provide data access– Catalog / Image data– Raw URL (REST Services) access
cl> vocatalog GSC2.2 180.0 0.0 0.25 insys=ecliptic cl> voimage 2MASS 180.0 0.0 0.25 cl> type getData(“http://iraf.net”)
• Compiled Tasks provide– Access to services/data not suited to CL functions
• Utility functions such as– Result table manipulation (clipping, selection, conversion, etc)– Display/overlay functionality– Coordinate manipulation/conversion
Sep 6, 2008 2008 NVO Summer School 5
Registry Access – Task Browser
• REGISTRY Task– Keyword search– Service Type– Bandpass– Arbitrary SQL constraint– Interactive browsing of results to further
constrain output• Very helpful when developing to find a set of
related resources you might want to offer in a task (e.g. Alternate access to a data service)
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: NVO Package
High-Level Applications
• Registry Browsing (i.e. Data Discovery)
cl> registry “galaxy cluster” svc=cone bandpass=x-ray
#No ShortName ServiceType Identifier
1 BAXGALCLUS CONE ivo://nasa.heasarc/baxgalclus
2 IPCULTSOFT CONE ivo://nasa.heasarc/ipcultsoft
3 M31XMMXRAY CONE ivo://nasa.heasarc/m31xmmxray
4 NORAS CONE ivo://nasa.heasarc/noras
5 REFLEX CONE ivo://nasa.heasarc/reflex
6 WARPS CONE ivo://nasa.heasarc/warps
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: VO-CL
Registry Query Interface str = regResolver (shortName,[svctype[,attr[,index]]])
N = nresolved ()
resource = regSearch (term [, orValues])
resource = regSearch (keywords, orValues)
resource = regSearch (sql, keywords, orValues)
resource = regSvcSearch (svcType, searchTerm, orValues)
count = regResultCount (resource)
str = regValue (resource, attr_list, resIndex)
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: VO-CL
DAL Interface
qres = dalConeSvc (url, ra, dec, sr)
qres = dalSiapSvc (url, ra, dec, rsize[, dsize[, fmt]])
count = dalRecordCount (qres)
stat = dalGetData (qres, recnum, fname)
val = dalGet[Str|Int|Dbl] (qres, attrname, recnum)
fname = getData (url, [fname])
Sep 6, 2008 2008 NVO Summer School 9
Data Access – CL Language
fname = getData (acref, [, filename])
• Provides general access to a URI– Returns a filename and so can be used as an
argument to a task– Uses default filename for opaque access to
temporary data– When accessing images, filename must be
specified with the file extension
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: VO-CL
Sample Script Task -- Messier Object Browser
procedure messier ()
begin
int qr, stat
string svc
svc = regResolver ("dss2","sia") # Find the DSS SIA service
for (i=1; i < 111; i=i+1) { # Loop over Messier objs
sesame ("M"//i, verb+) | scan (x,y) # Resolve name to coords
qr = dalSiapSvc (svc, x, y, 0.25) # Query for data
stat = dalGetData (qr, 0, "foo.fits") # Download 1st image
display ("foo.fits[0]", 1) # Display it
}
end
Sep 6, 2008 2008 NVO Summer School 11
NVO Package – Sampling of Tasks
• VOCATALOG – Cone Search • VOIMAGE – SIAP Search
– Any coord sys input, user's image, etc– Return table in variety of formats
• SESAME – Name resolver• DATASCOPE – Command-line toy version• VIZIER – Download Vizier Tables• SKYBOT – Find/Mark minor planets• FCHART - Create a finder chart
Sep 6, 2008 2008 NVO Summer School
Examples - FCHART
nvotools> lpar fchart
object = Object to plot
(image = "") Image name
(ra = INDEF) RA of position
(dec = INDEF) Dec of position
(inwcs = "icrs") Input coord system
(size = 0.2) Size (degrees)
(fields = "G_Lens,Xray,Radio,QSO") Objects to mark
(grid = yes) Overlay coordinate grid?
(mode = "ql")
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: NVO Package
SDSS Spectral Data Access
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: NVO Package
NVSS Radio Contours
NED Sources
HST Observations
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: NVO Package
Query by ObjectName
Image from DSSOverlays as before
Abell 2235
Sep 6, 2008 2008 NVO Summer School
IRAF Integration: NVO Package
Asteroid Detection Usingthe SkyBoT Service
Sep 6, 2008 2008 NVO Summer School