Mapping

class astropy.modeling.mappings.Mapping

Bases: astropy.modeling.Model

Allows inputs to be reordered, duplicated or dropped.

Parameters:

mapping : tuple

A tuple of integers representing indices of the inputs to this model to return and in what order to return them. See Advanced mappings for more details.

n_inputs : int

Number of inputs; if None (default) then max(mapping) + 1 is used (i.e. the highest input index used in the mapping).

name : str, optional

A human-friendly name associated with this model instance (particularly useful for identifying the individual components of a compound model).

meta : dict-like

Free-form metadata to associate with this model.

Raises:

TypeError

Raised when number of inputs is less that max(mapping).

Examples

>>> from astropy.modeling.models import Polynomial2D, Shift, Mapping
>>> poly1 = Polynomial2D(1, c0_0=1, c1_0=2, c0_1=3)
>>> poly2 = Polynomial2D(1, c0_0=1, c1_0=2.4, c0_1=2.1)
>>> model = (Shift(1) & Shift(2)) | Mapping((0, 1, 0, 1)) | (poly1 & poly2)
>>> model(1, 2)  
(17.0, 14.2)

Attributes Summary

inputs	The name(s) of the input variable(s) on which a model is evaluated.
inverse	A Mapping representing the inverse of the current mapping.
mapping	Integers representing indices of the inputs.
outputs	The name(s) of the output(s) of the model.

Methods Summary

eval(*args, **kwargs)	Deprecated since version 1.0.
evaluate(*args)	Evaluate the model on some input variables.

Attributes Documentation

inputs

The name(s) of the input variable(s) on which a model is evaluated.

inverse

A Mapping representing the inverse of the current mapping.

Raises:

`NotImplementedError`

An inverse does no exist on mappings that drop some of its inputs (there is then no way to reconstruct the inputs that were dropped).

mapping

Integers representing indices of the inputs.

outputs

The name(s) of the output(s) of the model.

Methods Documentation

eval(*args, **kwargs)

Deprecated since version 1.0: The eval function is deprecated and may be removed in a future version. Use Mapping.evaluate instead.

evaluate(*args)

Evaluate the model on some input variables.