aXe-2.3 is part of
STSDAS 3.14, which was released in August 2011.
Within STSDAS, aXe resides in the sub-package 'analysis.slitless.axe'.
Along with the release of aXe v2.3 there is also an updated version of the
aXe User Manual (pdf format).
In addition, the most recent version of the
(pdf format) may also be helpful when running the software.
- Fixed a bug in "drzprep" that was causing 2D stamp images to
have the wrong size (too short in the x/dispersion direction) when setting
DRZRESOLA in the .config file to value smaller than the physical pixel
size, in order to oversample the drizzled image.
- Fixed a bug in "drzprep" that was causing the calculated errors for
spectra extracted from sub-sampled 2D images with axedrizzle to be
too high by about a factor of 6.
- Modified the behavior of low-level routines called by the "axeprep"
task so that it no longer quits with an error if it encounters an object
in the input object list (IOL) with mag=99 (which is put there by
SExtractor when it can't compute a magnitude for an object). It will now
only issue a warning message and continue with processing. Entries for
these objects will be ignored anyway by later aXe processing step due to
the fact that their magnitudes exceed the MMAG_EXTRACT limit in the
- Fixed a bug in the "axedrizzle" task to prevent a divide-by-zero error
for object spectra that have all of their pixels rejected due to excessive
- Upgraded the syntax of Python "raise" error statements in several
modules to conform to new Python 2.7 syntax rules.
- Modified the drizzle method used by the "axedrizzle" task to check for
input/output file names that are >80 characters long, in order to prevent
the IRAF drizzle task from crashing on long file names.
- Upgraded several methods within the "axeprep" task to replace calls
to IRAF tasks imcopy, imrename, imarith, imexpression, and imstatistics
with equivalent Python, PyFITS, and numpy procedures. axeprep is now
completely free of IRAF tasks.
- Removed all calls to IRAF tasks from the drizzleobjects module and
replaced them with equivalent Python and PyFITS file utilities and
numpy array arithmetic.
- Removed all calls to IRAF tasks imcopy, imrename, and imexpression
from the fcubeobjs module and replaced them with equivalent Python, PyFITS,
and numpy operations. fcubeprep still contains a call to the IRAF/STSDAS
dither package task "blot".