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Basic Information on ellint


Task: ellint
Purpose: Integrate a Miriad image in elliptical annuli.
Categories: image analysis

        ELLINT integrates a Miriad image in elliptical annuli in the
        first two dimensions.  E.g. to find the radial brightness
        distribution, or flux density as a function of distance in a
        galaxy.  The integration is done separately for each image plane
        in the region included.
 
        The output consists of 6 columns. They are the
 
        outer radius (arcsec) of the annulus;
        number of pixels in the annulus;
        the average (median) in the annulus;
        the rms of the annulus;
        the sum in the annulus normalized by the volume of the primary
           beam (if there is one);
        the cumulative sum for all annuli so far.
 

Key: in
        Input image name. xyz images only. No default.

Key: out
        Optional output image containing the residuals from the average
        values in each annulus. By default this image is not created.
        See also options=spline to get better results for noise free
        images.

Key: region
        Region of image to be integrated. E.g.
          % ellint region=relpix,box(-4,-4,5,5)(1,2)
        integrates the center 10 x 10 pixels for image planes 1 and 2.
        Unmasked pixels within the bounding box are selected.
        The default region is the entire image.

Key: center
        The offset of the center of the annuli in arcsec from the
        reference pixel, measured in the directions of RA and DEC.

Key: pa
        Position angle of ellipse major axis in degrees. Default is 0
        (north).  PA is measured in the usual sense, N through E
        (counter clockwise).

Key: incline
        The ellipse is assumed to be a circular structure that appears
        elliptical because it is viewed at some inclination.  The
        "incline" parameter gives this inclination angle in degrees.
        Default=0. (face on)

Key: radius
        Inner and outer radii and step size along major axis in arcsecs.
        The default is the whole image in steps equal to the pixel size.

Key: telescop
        If you request that the fluxes be corrected for the primary beam
        (see OPTIONS), ELLINT will normally construct a primary beam
        type using information from the dataset.  However you can
        override this with a primary beam type of your own choosing.
        The primary beam type can either be a telescope name whose
        primary beam is known (e.g. Hatcreek, VLA, ATCA, etc) or you can
        select a Gaussian form with "gaus(xxx)".  Here xxx is the
        primary beam FWHM in arcseconds.  For example gaus(120) is a
        telescope with a 120 arcsec primary beam.

Key: scale
        Scale factor applied to the amplitudes before printing them.
        Default=1.

Key: options
        Task enrichment options.  Minimum match is active.
          pbcorr    This causes the images to be corrected for primary
                    beam attenutation before integrating.
          median    Find the median of each annulus instead of the
                    average.
          mode      Find the mode of each annulus instead of the
                    average.
          natural   Assume keywords "center" and "radius" are in natural
                    units rather than arcsec.
          table     Output ring data in logfile. No fitting done.
                    Logfile now contains coordinates w.r.t. the
                    reference pixel (in arcsec), the image value, and
                    the radius in the disk defined by PA and INCLINE.
          spline    use a spline fit unstead of a step function to
                    estimate the intensity at any radius for residual
                    images

Key: medsmooth
         Smoothing option of radial profile when option=median is used
         in residual map computation. Default: 0
 

Key: log
        The output log file. The default is the terminal.
 
Revision: 1.7, 2013/08/30 01:49:21 UTC

Generated by miriad@atnf.csiro.au on 21 Jun 2016