lsst.ip.isr.linearize.LinearizePolynomial Class Reference

Inheritance diagram for lsst.ip.isr.linearize.LinearizePolynomial:

Public Member Functions
	__call__ (self, image, **kwargs)

Static Public Attributes
	LinearityType = None

Detailed Description

Correct non-linearity with a polynomial mode.

.. code-block::

    corrImage = uncorrImage + sum_i c_i uncorrImage^(2 + i)

where ``c_i`` are the linearity coefficients for each amplifier.
Lower order coefficients are not included as they duplicate other
calibration parameters:

``k0``
    A coefficient multiplied by ``uncorrImage**0`` is equivalent to
    bias level.  Irrelevant for correcting non-linearity.
``k1``
    A coefficient multiplied by ``uncorrImage**1`` is proportional
    to the gain.  Not necessary for correcting non-linearity.

Definition at line 816 of file linearize.py.

Member Function Documentation

__call__()

lsst.ip.isr.linearize.LinearizePolynomial.__call__	(		self,
			image,
		**	kwargs )

Correct non-linearity.

Parameters
----------
image : `lsst.afw.image.Image`
    Image to be corrected
kwargs : `dict`
    Dictionary of parameter keywords:

    ``coeffs``
        Coefficient vector (`list` or `np.ndarray`).
        If the order of the polynomial is n, this list
        should have a length of n-1 ("k0" and "k1" are
        not needed for the correction).
    ``log``
        Logger to handle messages (`logging.Logger`).

Returns
-------
output : `tuple` [`bool`, `int`]
    If true, a correction was applied successfully.  The
    integer indicates the number of pixels that were
    uncorrectable by being out of range.

Definition at line 836 of file linearize.py.

Member Data Documentation

LinearityType

lsst.ip.isr.linearize.LinearizeBase.LinearityType = None

staticinherited

Definition at line 706 of file linearize.py.

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The documentation for this class was generated from the following file:

• python/lsst/ip/isr/linearize.py