B.9.2 Examples

Here are some examples of mocshape:

stilts mocshape in=survey.vot coords='array(alpha,delta)' shape=point
                mocfmt=fits out=sfoot.fits

Generates a FITS Space MOC file from the alpha and delta columns of a table interpreted as points. The coords parameter must be a 2-element array for shape=point, and this is constructed from the table's alpha and delta columns using the array function of the expression language. Since no order parameter is supplied, the default HEALPix order is used. This command does the same job as the pixfoot command with parameters ra=alpha dec=delta.

stilts mocshape in=obscore.vot coords=s_region order=4 mocfmt=ascii

Generates an order 4 Space MOC describing the union of all the regions described in the s_region column of an ObsCore table. It is written to standard output in ASCII format. Since the shape parameter is not specified, the command will examine the column metadata for the s_region column to determine the shape that it specifies; for instance xtype values of "point", "circle", "polygon", "stc-s" or "moc" will be understood. If it can't determine from the metadata what kind of shape information is held in the s_region column an error will result, and you can run it with the shape parameter set according to the actual shape type.

stilts mocshape moctype=stmoc
       in=https://aladin.cds.unistra.fr/java/stmoc/Ceres_Ephemerids.vot
       shape=point coords='array(hmsToDegrees(RA),dmsToDegrees(DEC))' order=8
       t0=date tshape=day-radius t1=0.25 ttype=iso8601
       mocfmt=fits out=ceres-stmoc.fits

Generates a space-time MOC based on positions and observation times from a given file. The sky positions are given in sexagesimal, so the hmsToDegrees and dmsToDegrees functions are used to convert them to degrees. The order of the space MOC is specified explicitly. The time values are read from the Date column in ISO-8601 format; each of these epoch values is considered to represent a 0.5-day interval centered on the given date. Output is to an STMOC FITS file which encodes the region of space-time described by the supplied ephemerides.