analysis.galfun module¶
Multipurpose module that contains important functions ranging from managing parameters of generated galaxies to extracing information from relevant files.
-
class
analysis.galfun.
GParameters
(project=None, id_params=None, omit={})[source]¶ Bases:
object
Class that manages galaxies parameters obtained from galaxies.csv
This class reads a galaxies.csv file located in the specified project directory and extracts the parameters of each galaxy contained in it.
- Args:
- project(str): String point to the directory specified by the user.
id_params(dict): See Attributes for details. Makes it possible to
create a
GParameters
object without galaxies.csv file. - Attributes:
- omit_fit(dict): Dictionary defined in containing
- the parameters that should not be included in the analysis for a particular galaxy model but could be ecessary for drawing the galaxy.
- id_params(dict): Dictionary whose keys are the ids of each of the
- galaxies specified in galaxies.csv, and that map
to another dictionary that can be taken in by
getGalaxyModel()
- params(dict): Dictionary that encodes the same information as
- id_params but in a different form. Combines each of the dictionaries contained in id_params into a single dictionary that contains all parameters but in the form param_#.
- fit_params(dict): Dictionary similar to the params attribute but
- without the parameters specified in omit_fit.
- nfit_params(dict): Dictionary that contains all the parameters not
- contained in fit_params. Usually used for kwargs in conjunction with fit_params to draw Galaxies.
- ordered_fit_names(list): A list containing the keys of fit_params
- in a desirable order.
num_galaxies(int): Number of galaxies specified.
-
static
convertId_Params
(id_params, omit_fit={})[source]¶ Converts id_params to the format of
params
.Parameters: Returns: A dictionary of params (dict).
-
static
convertParams_Id
(params)[source]¶ Convert a dictionary params in the format of
params
to a dictionary in the formatid_params
-
class
analysis.galfun.
ImageRenderer
(pixel_scale=None, nx=None, ny=None, stamp=None, project=None, bounds=None, mask=None)[source]¶ Bases:
object
Object used to produce the image of a galaxy.
Parameters: - pixel_scale (float) – Pixel_scale to use in the image (ratio of pixels to arcsecs)
- nx (float) – Width of the image in pixels.
- ny (float) – height of the image in pixels.
- stamp (int) – optional, galsim.Image of appropiate dimensions to draw the image. does not actually use whatever was originally in the stamp.
- bounds (tuple) – When drawn, the image will be clipped to these bounds.
- mask (
np.array
) – the pixels selected in this mask will be set to 0.
This object is made so it can be passsed in to a class
analysis.fisher.Fisher
object.
-
analysis.galfun.
addNoise
(image, snr, noise_seed=0)[source]¶ Set gaussian noise to the given galsim.Image.
Parameters: Returns: A
galsim.Image
, variance_noise tuple. The image is the noisy version of the original image and variance_noise is the noise variance on each pixel due to the added noise.
-
analysis.galfun.
getGalaxiesModels
(fit_params=None, id_params=None, g_parameters=None, **kwargs)[source]¶ Return the model of a set of galaxies.
- One of the the following must be specified:
- fit_params (and nfit_params as **kwargs. Used specially in
runfits.py
). id_params g_parameters (from which id_params is extracted.)
This function generates each of the galaxies specified in id_params and then sums them together to get a final galaxy.
Parameters: - fit_params (dict) – Partial form of id_params that only includes the
parameters to be used for the fit.
For details,
GParameters
- id_params (dict) – Dictionary containing each of the galaxies
parameters. For details,
GParameters
- g_parameters (
GParameters
) – An object containing different forms of the galaxy parameters. - image (bool) – If :bool:True returns an galsim.Image otherwise it
- a np.array (returns) –
Returns: A
galsim.GSObject
-
analysis.galfun.
getGalaxyModel
(params)[source]¶ Return the image of a single galaxy optionally drawn with a psf.
Look at
analysis.models
to figure out which galaxy models and psf models are supported as well as their corresponding implemented parameters. You can even add your own galaxies if desired.Parameters: - params (dict) – Dictionary containing the information of a single
- where the keys is the name (galaxy) –
- are the values of the parametes. (values) –
Returns: A
galsim.GSObject