To create a FITS file, called lcoutput.ds, which is composed of the three lightcurves, lightcurve1.ds, lightcurve2.ds, lightcurve3.ds, a command such as,
elcbuild sets='lightcurve1.ds, lightcurve2.ds, lightcurve3.ds' outset=lcoutput.ds
can be used.
