centroid_sources

photutils.centroids.centroid_sources(data, xpos, ypos, box_size=11, footprint=None, error=None, mask=None, centroid_func=<function centroid_com>)[source]

Calculate the centroid of sources at the defined positions.

A cutout image centered on each input position will be used to calculate the centroid position. The cutout image is defined either using the box_size or footprint keyword. The footprint keyword can be used to create a non-rectangular cutout image.

Parameters
dataarray_like

The 2D array of the image.

xpos, yposfloat or array-like of float

The initial x and y pixel position(s) of the center position. A cutout image centered on this position be used to calculate the centroid.

box_sizeint or array-like of int, optional

The size of the cutout image along each axis. If box_size is a number, then a square cutout of box_size will be created. If box_size has two elements, they should be in (ny, nx) order. Either box_size or footprint must be defined. If they are both defined, then footprint overrides box_size.

footprintndarray of bools, optional

A 2D boolean array where True values describe the local footprint region to cutout. footprint can be used to create a non-rectangular cutout image, in which case the input xpos and ypos represent the center of the minimal bounding box for the input footprint. box_size=(n, m) is equivalent to footprint=np.ones((n, m)). Either box_size or footprint must be defined. If they are both defined, then footprint overrides box_size.

maskarray_like, bool, optional

A 2D boolean array with the same shape as data, where a True value indicates the corresponding element of data is masked.

errorarray_like, optional

The 2D array of the 1-sigma errors of the input data. error must have the same shape as data. error will be used only if supported by the input centroid_func.

centroid_funccallable, optional

A callable object (e.g., function or class) that is used to calculate the centroid of a 2D array. The centroid_func must accept a 2D ndarray, have a mask keyword and optionally an error keyword. The callable object must return a tuple of two 1D ndarray, representing the x and y centroids. The default is centroid_com.

Returns
xcentroid, ycentroidndarray

The x and y pixel position(s) of the centroids.