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Debiasing API

AstrometricDebiasMap(bias_data, supported_codes, used_codes, n_side)

Map catalog code and sky position to optical bias values.

Initialize an astrometric debias map.

Parameters:

Name Type Description Default
bias_data Float[ndarray, N]

Bias table with shape N_pixel N_catalog 4. The last axis stores dRA, dDEC, dPMRA, and dPMDEC.

required
supported_codes list or ndarray

Catalog codes in the same order as the table.

required
used_codes list or ndarray

Catalog codes that can be corrected.

required
n_side int

HEALPix NSIDE value.

required

get_bias(obs)

Return optical bias arrays for one observation set.

Parameters:

Name Type Description Default
obs ObservationData

Observation data for one target.

required

Returns:

Type Description
Float[ndarray, 'N 2']

Optical bias arrays in radians. Columns are right ascension and declination.

from_bias2018(filepath=DEFAULT_BIAS_FILENAME) classmethod

Build a debias map from the Eggl et al. 2018 table file.

Parameters:

Name Type Description Default
filepath str

Path to the bias table.

DEFAULT_BIAS_FILENAME

Returns:

Type Description
AstrometricDebiasMap

Loaded debias map.

DebiasPolicy

Bases: ABC

Base class for optical debias policies.

name abstractmethod property

Return the policy name.

bias(obs) abstractmethod

Return optical bias arrays.

Parameters:

Name Type Description Default
obs ObservationData

Observation data for one target.

required

Returns:

Type Description
DebiasResult

Bias arrays in radians.

DebiasResult

Bases: NamedTuple

Bias arrays returned by a debias policy.

EgglDebiasPolicy()

Bases: DebiasPolicy

Policy for the Eggl et al. 2018 astrometric debias map.

Initialize the policy with the default debias map.

name property

Return the policy name.

bias(obs)

Return Eggl et al. 2018 bias arrays for optical observations.

Parameters:

Name Type Description Default
obs ObservationData

Observation data for one target.

required

Returns:

Type Description
DebiasResult

Bias arrays in radians.

NoDebiasPolicy

Bases: DebiasPolicy

Policy that returns zero optical bias.

name property

Return the policy name.

bias(obs)

Return zero bias arrays for each optical observation.

Parameters:

Name Type Description Default
obs ObservationData

Observation data for one target.

required

Returns:

Type Description
DebiasResult

Zero bias arrays in radians.