rail.interactive.creation.degraders.grid_selection module

rail.interactive.creation.degraders.grid_selection.grid_selection(**kwargs)

Uses the ratio of HSC spectroscpic galaxies to photometric galaxies to portion a sample into training and application samples. Option to implement a color-based redshift cut off in each pixel. Option of further degrading the training sample by limiting it to galaxies less than a redshift cutoff by specifying redshift_cut.

color_redshift_cut: True or false, implements color-based redshift cut. Default
is True.
    If True, ratio_file must include second key called 'data' with magnitudes,
    colors and spec-z from the spectroscopic sample.
percentile_cut: If using color-based redshift cut, percentile in spec-z above
which redshifts will be cut from training sample. Default is 99.0
scaling_factor: Enables the user to adjust the ratios by this factor to change
the overall number of galaxies kept.  For example, if you wish
    to generate 100,00 galaxies but only 50,000 are selected by default, then
    you can adjust factor up by a factor of 2 to return more galaixes.
redshift_cut: redshift above which all galaxies will be removed from training
sample. Default is 100
ratio_file: hdf5 file containing an array of spectroscpic vs. photometric
galaxies in each pixel. Default is hsc_ratios.hdf5 for an HSC based selection
settings_file: pickled dictionary containing information about colors and
magnitudes used in defining the pixels. Dictionary must include the following
keys:
    'x_band_1': string, this is the band used for the magnitude in the color
    magnitude diagram. Default for HSC is 'i'.
    'x_band_2': string, this is the redder band used for the color in the color
    magnitude diagram.
    if x_band_2 string is not set to '' then the grid is assumed to be over
    color and x axis color is set to x_band_1 - x_band_2, default is ''.
    'y_band_1': string, this is the bluer band used for the color in the color
    magnitude grid. Default for HSC is 'g'.
    'y_band_2': string, this is the redder band used for the color in the color
    magnitude diagram.
    if y_band_2 is not set to '' then the y-band is assumed to be over color and
    is set to y_band_1 - y_band 2.
    'x_limits': 2-element list, this is a list of the lower and upper limits of
    the magnitude. Default for HSC is [13, 16],
    'y_limits': 2-element list, this is a list of the lower and upper limits of
    the color. Default for HSC is [-2, 6]}

NOTE: the default ‘HSC’ grid file, located in rail/examples_data/creation_data/data/hsc_ratios_and_specz.hdf5, is based on data from the Second HSC Data Release, details of which can be found here: Aihara, H., AlSayyad, Y., Ando, M., et al. 2019, PASJ, 71, 114 doi: 10.1093/pasj/psz103

Update(Apr 16 2024): Now inherit from selector and implement the _select() instead of run()

—

The main interface method for Selector.

Adds noise to the input catalog

This will attach the input to this Selector

Then it will call the select() which add a flag column to the catalog. flag=1 means selected, 0 means dropped.

If dropRows = True, the dropped rows will not be presented in the output catalog, otherwise, all rows will be presented.

Finally, this will return a PqHandle providing access to that output data.

—

This function was generated from the function rail.creation.degraders.grid_selection.GridSelection.__call__

Parameters:

sample (TableLike, required) – The sample to be selected
drop_rows (bool, optional) – Drop selected rows from output table Default: True
seed (int, optional) – random seed for reproducibility Default: 12345
color_redshift_cut (bool, optional) – using color-based redshift cut Default: True
percentile_cut (float, optional) – percentile cut-off for each pixel in color-based redshift cut off Default: 99.0
redshift_cut (float, optional) – cut redshifts above this value Default: 100.0
ratio_file (str, optional) – path to ratio file Default: rail/examples_data/creation_data/data/hsc_ratios_and_specz.hdf5
settings_file (str, optional) – path to pickled parameters file Default: rail/examples_data/creation_data/data/HSC_grid_settings.pkl
scaling_factor (float, optional) – multiplicative factor for ratios to adjust number of galaxies kept Default: 1.588

Returns:

A handle giving access to a table with selected sample

Return type:

pandas.core.frame.DataFrame