add_beam¶
- astropy.visualization.wcsaxes.add_beam(ax, header=None, major=None, minor=None, angle=None, corner='bottom left', frame=False, borderpad=0.4, pad=0.5, **kwargs)[source]¶
Display the beam shape and size
- Parameters:
- ax
WCSAxes
WCSAxes instance in which the beam shape and size is displayed. The WCS must be celestial.
- header
Header
, optional Header containing the beam parameters. If specified, the
BMAJ
,BMIN
, andBPA
keywords will be searched in the FITS header to set the major and minor axes and the position angle on the sky.- major
python:float
orQuantity
, optional Major axis of the beam in degrees or an angular quantity.
- minor
python:float
, orQuantity
, optional Minor axis of the beam in degrees or an angular quantity.
- angle
python:float
orQuantity
, optional Position angle of the beam on the sky in degrees or an angular quantity in the anticlockwise direction.
- corner
python:str
, optional The beam location. Acceptable values are
'left'
,'right'
,'top'
, ‘bottom’,'top left'
,'top right'
,'bottom left'
(default), and'bottom right'
.- framebool, optional
Whether to display a frame behind the beam (default is
False
).- borderpad
python:float
, optional Border padding, in fraction of the font size. Default is 0.4.
- pad
python:float
, optional Padding around the beam, in fraction of the font size. Default is 0.5.
- kwargs
Additional arguments are passed to
matplotlib.patches.Ellipse
.
- ax
Notes
This function may be inaccurate when:
The pixel scales at the reference pixel are different from the pixel scales within the image extent (e.g., when the reference pixel is well outside of the image extent and the projection is non-linear)
The pixel scales in the two directions are very different from each other (e.g., rectangular pixels)