Task uvsector will flag a sector of visibility data with a given
u-v position angle (or hour angle). While you can give the
position angle of the sector to be flagged directly (via the
angle parameter), it is more convenient to indicate the position
angle indirectly via the stripe direction in an image. How do
you specify a stripe direction? You do this by specifying a
long, thin region in a image. Normally you will generate the
region by using cgcurs (see Section 17.3 for more information on
cgcurs). With cgcurs, you display a greyscale of the image, and
then use a cursor to selection a long, thin, region containing
the crest of a single stripe. The selected region is then
written into a text file, cgcurs.region. While this may be a
rather odd way to define a direction, it allows uvsector to use
the interactive facilities of cgcurs. Typical inputs to use
cgcurs are |in=vela.icln||Input image (probably CLEANed).|
|range=||Set the range to highlight the stripes.|
|device=/xs||PGPLOT device - Xwindows here.| |o