class pvextractor.PathFromCenter(center, length=None, angle=None, sample=2, width=None)[source]

Bases: pvextractor.Path

A simple path defined by a center, length, and position angle.


center : SkyCoord

The center of the path

length : Quantity

The length of the path in angular units

angle : Quantity

The position angle of the path, counter-clockwise

sample : int

How many points to sample along the path. By default, this is 2 (the two end points. For small fields of view, this will be a good approximation to the path, but for larger fields of view, where spherical distortions become important, this should be increased to provide a smooth path.

width : None or float or Quantity

The width of the path. If coords is passed as a list of pixel positions, the width should be given (if passed) as a floating-point value in pixels. If coords is a coordinate object, the width should be passed as a Quantity instance with units of angle. If None, interpolation is used at the position of the path.


The orientation of the final path will be such that for a position angle of zero, the path goes from South to North. For a position angle of 90 degrees, the path will go from West to East.