imgnonlin

sofia_redux.instruments.forcast.imgnonlin.imgnonlin(data, header, siglev=None, variance=None)

Corrects for non-linearity in detector response due to general background.

The header must contain the information to determine the camera. If siglev is not passed, the header must also contain a keyword (NLINSLEV) to indicate the background level and size of the section used to calculate the level. In practice, this means that sofia_redux.instruments.forcast.background should be run first to calculate the background level.

Parameters:

datanumpy.ndarray

Input data array (nimage, nrow, ncol)

headerastropy.io.fits.header.Header

Input FITS header. Will be updated with a HISTORY message

siglevarray_like, optional

Background level. There should be a single value for each input frame

variancenumpy.ndarray, optional

Variance array (nimage, nrow, ncol) to update in parallel with the data frame.

Returns:

numpy.ndarray, numpy.ndarray

The linearity corrected array (nimage, nrow, ncol) or (nrow, ncol) The propagated variance array (nimage, nrow, ncol) or (nrow, ncol)