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drz2pet axe



drz2pet -- generate a PET froma list of 2D drizzled grism images


drz2pet inlist config


List to give input images.
Name of aXe configuration file(s) to be used.
(opt_extr = no) [yes|no]
Compute and store optimal weights.
(back = no) [yes|no]
Create a background PET from 2D drizzled background images?
(in_af = "") [string]
Name to use for the input Aperture file instead of the default.
(out_pet = "") [string]
Name to use for the output PET file (instead of the default).


The task "drz2pet" combines the 2D drizzled grism images given in "inlist" into a single PET. The task needs an OAF/BAF whose name is derived from the name of inlist. The sequence of beams in the OAF/BAF must coincide with sequence of images in "inlist". Also the configuration file must reflect the properties of the ideal 2D drizzled, ideal grism spectra (trace description).

The task "axedrizzle" produces all the necessary input files for "drz2pet", and usually "drz2pet" is implicitly run within "axedrizzle" ("makespc=YES").

With opt_extr="no" the task updates the weight image and sets the weight proportional to the relative exposure time within the set of pixels that will be contracted to an individual resolution element. This is necessary to properly take into account the uneven distributed exposure time introduced by the masking of bad pixels/cosmic ray hist and objects which sometimes are at the border of a chip.

With opt_extr="yes" the task computes optimal weights from the extensions [WEIGH] and [VAR] in the 2D drizzled grism images. The optimal weights are stored in the PET and used in subsequent calls to pet2spc on that data set.


The name of the PET created by this task is based on the name of the input list "inlist". The task creates a file <inlist>.PET.FITS for "back=NO" and <inlist>.PET.fits for "back=YES", respectively.


1. Create an object PET from the images given in "test_aXe_2.lis". The names for the image list and the configuration file are typical filenames given in "axedrizzle". The PET name is then "test_aXe_2.PET.fits".

    ax> drz2pet inlist="test_aXe_2.lis" config="test_aXe.conf" back="no"

2. As in 1., but compute optimal weights instead of exposure time weights.

    ax> drz2pet inlist="test_aXe_2.lis" config="test_aXe.conf"
                back="NO" opt_extr="yes"




Refer to manual for more detailed information about using this aXe task:


axedrizzle, pet2spc

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