Module: morphology¶

Overview¶

This modules provides the implementation of the functions for the extraction of morphometric features, related to Hu_moments

Classes relations¶

Classes and Inheritance Structure¶

Summary¶

`do_morphometric_features_extraction_process_func`
`FeaturesArray`
`DoMorphometricFeaturesExtraction`

Module API¶

eval_Concentration(r_20, r_80, r_50, r_90)[source]¶

Evaluates the concentration parameter:

\[C=5log(r_{80}/r_{20})\]

where \(r_{80}\) and \(r_{20}\) are the radii of the circular discs containing respectively 80% and 20% of the total cluster image flux.

Parameters:

r_20 : Optional

r_80 : Optional

Returns:

Concentration parameter float

eval_Gini(flux_array)[source]¶

The Gini factor [Lotz:2004] indicates the distribution of the light among pixels. A value of Gini equal to 1 would indicate that all the light is concentrated in one pixel, on the contrary, a lower value would indicates that the light is distributed more evenly amongst the pixels, with Gini factor equal to 0, if all the pixels have the s ame flux value.

Parameters:

flux_array : 1dim numpy array,

Returns:

Gini factor : float

eval_M20(flux_array, x, y, x_c, y_c)[source]¶

Parameters:

flux_array

x

y

x_c

y_c

eval_asymmetry(cluster_image, x_c, y_c, r_petrosian)[source]¶

Parameters:

cluster_image

x_c

N

eval_clumpiness(cluster_image, cluster_blurred_image)[source]¶

Parameters:

cluster_image

cluster_blurred_image

eval_r_Petrosian(I, r, s, image_array=None, plot=False)[source]¶

Parameters:

r_coords

r_max

flux_array

get_cluster_morphology_morphometric_features(cluster, cluster_image, image_centroid, surf_bright_profile, group_name='morph', name_flag=None, blurring_scale=0.25)[source]¶

Function to extract galaxy morphometric features for :.... . The try/except statement allows to return np.nan features

Parameters:

cluster : :class:`asterism.core.clustering.source_cluster.SourceCluster2Dim’

cluster object from whicht to extract the features

cluster_image : 2d array

image used to evaluate the asymmetry and the clumpiness

image_centroid : tuppolar_coords.theta,theta_pdf,theta_pdf_xle (x,y)

tuple storing the source centroid coordinate for the cluster_image,

surf_bright_profile : :class: asterism.core.photometry.surface_brightness_profile.ImageBrigthnessRadialProfile

instance object for the surface brightness profile

group_name : str

the group name for the features (see MorphometricFeatures)

name_flag : str

the flag name for the features (see MorphometricFeatures)

Returns:

MorphometricFeatures : MorphometricFeatures

The class storing the features with their names and dtypes

Module: morphology¶