circle - select a circular region

  circle[/qualifiers]

A circular region is selected using the cursor. The results of the selection are written to a region file. This file has by default the same name as the image file, with the extension .reg.

A region filename can be specified using the /file= qualifier. The regions are by default inclusive. The /exclusive qualifier will create an exclusive region. Each new region selection is added to the region file, unless the /new qualifier is given. This applies to all region selections, including box. The coordinates written to the file are in the original unbinned pixels, even if the image has been rebinned.

circle/excluded

The define region will be excluded.

circle/regionfile=filename

Specify the name of the region file. Otherwise the default will be the imagename.reg

circle/new

Start a new region definition. If /new is not specified, then regions will be added to the existing file.

circle/displayonly

Draw the contents of a region file on the current image

Examples:

circle                       ! make a circle region selection
circle/excluded              ! make an excluded circle region selection
circle/filename=fred.reg     ! write the cirle region select to a file
circle/file=fred.reg/disp    ! display the region file fred.reg