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B.29.2 Examples

stilts tcube in=2QZ_6QZ_pubcat.fits out=ccm.fits \
             cols='Bj_R U_Bj Bj' binsizes='0.05 0.05 0.5' bounds='-2:1 -3:2 :'
Calculates a 3-dimensional colour-colour-magnitude grid from three existing columns in a table. The bin (pixel) sizes are specified. The data bounds are specified explicitly for the (first two) colour dimensions, but for the (third) magnitude dimension it is determined from the minimum and maximum values the data in that column of the table. The output is a three-dimensional FITS cube containing the number of points in each cell.
stilts tcube in=iras_psc.vot out=flux60_map.fits \
             icmd='addskycoords fk5 galactic ra dec glat glon' \
             cols='glat glon' nbins='400 200' \
             scale=Fnu_60 combine=sum 
Calculates a map of integrated fluxes in galactic coordinates from a catalogue of IRAS point sources. The output is a two-dimensional FITS image representing the sky in galactic coordinates, with each pixel containing the sum of Fnu_60 fluxes from objects in that rectangle of (glat,glon> space. Bounds are determined automatically from the data, and the number of pixels in each dimension (400 in latitude and 200 in longitude) are specified, which means that the pixel sizes don't have to be. Since the input table contains sky positions in equatorial coordinates rather than galactic ones, the addskycoords filter is used to preprocess the data before the cube generation step (see Section 6.1).


Next Previous Up Contents
Next: tloop: Generates a single-column table from a loop variable
Up: tcube: Calculates N-dimensional histograms
Previous: Usage

STILTS - Starlink Tables Infrastructure Library Tool Set
Starlink User Note256
STILTS web page: http://www.starlink.ac.uk/stilts/
Author email: m.b.taylor@bristol.ac.uk
Mailing list: topcat-user@jiscmail.ac.uk