SIP¶

class
astropy.modeling.polynomial.
SIP
(crpix, a_order, b_order, a_coeff={}, b_coeff={}, ap_order=None, bp_order=None, ap_coeff={}, bp_coeff={}, n_models=None, model_set_axis=None, name=None, meta=None)[source]¶ Bases:
astropy.modeling.Model
Simple Imaging Polynomial (SIP) model.
The SIP convention is used to represent distortions in FITS image headers. See [1] for a description of the SIP convention.
 Parameters
 crpixlist or ndarray of length(2)
CRPIX values
 a_orderint
SIP polynomial order for first axis
 b_orderint
SIP order for second axis
 a_coeffdict
SIP coefficients for first axis
 b_coeffdict
SIP coefficients for the second axis
 ap_orderint
order for the inverse transformation (AP coefficients)
 bp_orderint
order for the inverse transformation (BP coefficients)
 ap_coeffdict
coefficients for the inverse transform
 bp_coeffdict
coefficients for the inverse transform
References
Attributes Summary
Methods Summary
__call__
(u, v[, model_set_axis, …])Evaluate this model using the given input(s) and the parameter values that were specified when the model was instantiated.
evaluate
(x, y)Evaluate the model on some input variables.
Attributes Documentation

inputs
= ('u', 'v')¶

outputs
= ('x', 'y')¶
Methods Documentation

__call__
(u, v, model_set_axis=None, with_bounding_box=False, fill_value=nan, equivalencies=None)¶ Evaluate this model using the given input(s) and the parameter values that were specified when the model was instantiated.