cymorph.concentration.Concentration

class cymorph.concentration.Concentration(clean_image, radius1=0.8, radius2=0.2, rp=None, growth_curve=None, growth_radii=None)

Extracts concentration metric from the supplied image. Additionally, can calculate petrosian radius, growth curve and growth radii if not supplied.

Parameters

  • clean_image (2-d ndarray) – Clean image data array.

  • radius1 (int, optional) – Value of outer radius that will enclose a give amount of galaxy flux. Default is 0.8 (80% of all flux).

  • radius2 (int, optional) – Value of inner radius that will enclose a give amount of galaxy flux. Default is 0.2 (20% of all flux).

  • rp (float, optional) – Value of petrosian radius in pixels. If not supplied, will be calculated at ETA=0.2.

  • growth_curve (1-d ndarray) – Array of flux (in counts) growth curve of a galaxy. If not supplied, will be calculated.

  • growth_radii (1-d ndarray) – Array of flux growth radii (in pixels) of a galaxy. This array should be the same length as growth_curve, where each value will correspond to flux value and respective radius that encloses it. If not supplied, will be calculated.

__init__(clean_image, radius1=0.8, radius2=0.2, rp=None, growth_curve=None, growth_radii=None)

Methods

__init__(clean_image[, radius1, radius2, ...])

get_concentration()

Returns a concentration value

get_petrosian_radius()

Return petrosian radius