[News] Updates

[Roeland Rengelink]

Hi,

Here's a summary of recent changes to the astro-wise code base.


PixelMap
========

We've introduced new PixelMap objects. These objects represent 
eclipse.pixelmap objects storing binary masks, where the pixelvalue 1 
means good, and 0 means bad.

The following persistent objects have beed defined

PixelMap          (the root pixelmap object)
    HotPixelMap
    ColdPixelMap
    SaturatedPixelMap
    CosmicMap

Many objects now have references to one or more PixelMap objects that 
are used to construct masks or weights on the fly, using the following 
idiom:

# select attributes not equal to None
valid_maps = filter(None, [self.hot, self.cold, self.saturated])

# combine to produced one eclipse.pixelmap object
mask = PixelMap.combine_pixelmaps(valid_maps)

# Use this, and a flat to produce a weight
weight = self.flat.image * mask.as_image()

where self.hot, self.cold, self.saturated are attributs that may be None 
(hence the filter), or HotPixelMap, ColdPixelMap, or SaturatedPixelMap 
respectively

The following objects are being deprecated:

(Base/Master)WeightFrame - Use WeightFrame, or on-the-fly processing
(Base/Master)FlagFrame   - Flag frames are no longer used
(Hot/Cold)PixelFame      - Use (Hot/Cold)PixelMap instead
MaskFrame                - produce mask on-the-fly from PixelMap objects

Objects that now refer to PixelMap objects include:

CosmicMap, DomeFlatFrame, FringeFrame, MasterFlatFrame, 
ReducedScienceFrame, TwilightFlatFrame, WeightFrame

ScienceFrame
============

Note that the procedure to produce ScienceFrame objects has also been 
streamlined. To get from a RawScienceFrame object to a ScienceFrame 
object, the following intermediate objects have to be made

1. SaturatedPixelMap
2. ReducedScienceFrame
3. CosmicMap
4. WeightFrame
5. Catalog, AstrometricCatalog, LongAstrom
6. ScienceFrame

See ScienceFrame for more details (docs still sparse, but a the code is 
a lot more self-explanatory)

Misc
====

Many attribute names have been changed to enhance consistency. Danny is 
maintaing the DB-evolution overview for this.

Please note improved in-line documentation for: Catalog, WeightFrame, 
PixelMap, HotPixelMap, SaturatedPixelMap, GainLinearity.


Merry Christmas, and see you next year.

Roeland