\section{Bugs and Release Notes}
This section lists known bugs (or strange features) that are known
at the date of release of the documentation, and the list of changes
since previous releases.

Notes since Documentation release of Version 3.2, dated  Jan, 30th, 2022

\subsection{Recent changes in repository}
This section gives the changes made 
since the last documentation release (as dated above). The changes 
are available in the working repository, but may not be distributed 
in any Gildas release yet.  

\begin{itemize}
\item{05-Jul-2022} Add the \com{MAP\_POLAR} command
This corresponds to revision 3.4-1 of the Documentation.
\item{29-Jun-2022} Ensure \qom{READ} handles properly Random Frequency Axis in UVFITS format
\item{29-Jun-2022} Ensure \qom{UV\_EXTRACT} works with Random Frequency Axis
\item{22-Apr-2022} Improve \qom{UV\_PREVIEW} command
\item{12-Apr-2022} Support for command \qom{STOKES} on internal buffers.
\item{23-Mar-2022} Introduce the \lang{IMAGER} language, and the
\com{PIPELINE} command. This corresponds to revision 3.3 of the
Documentation.
\end{itemize}

\subsection{Known Bugs}
This section contains the list of bugs known as of \today, or recently corrected.

\begin{itemize}
  \item{Corrected 29-Jun-2022} \qom{STOKES} command had incorrect derivation from H-V polarization
  \item{corrected 09-Jun-2022} Debug \qom{UV\_FLAG} command - Allow to use without Display.
  \item{corrected 13-Apr-2022} \qom{MAP\_COMBINE} and \qom{COMBINE} were not supporting
  big files.  
  \item{corrected 12-Apr-2022} \qom{UV\_RESIDUAL} was not working on a non-sorted Mosaic data set.
  This could only happen by reading the Clean Component Table after reading the UV data, without
  any imaging step.
  \item{Corrected 09-Mar-2022} \qom{CCT\_MERGE} Concatenation was improper
  \item{Corrected 07-Mar-2022} Beam size derivation was incorrect when an ANGLE was specified
  \item{Corrected 08-Feb-2022} \qom{UV\_RESTORE} was not using fixed beam size.
  \item{Corrected 18-Jan-2022} \texttt{SINGLEDISH} data was incorrectly read, probably since
20-Sep-2021 (v1.53 of read.f90). Improper values were thus used by the \qom{UV\_SHORT} command
(Discovered 17-Jan-2022 only).
  \item{Corrected 12-Jan-2022} Mosaic offsets were improperly computed by command
\qom{UV\_FIELDS} since 29-Jul-2021 (bug reported 10-Jan-2022). The script
\texttt{@ fits\_to\_uvt} was thus leading to wrong pointing offsets.
  \item{Corrected 10-Jan-2022} A improper interaction between scripts was causing
strange behaviour when switching between \qom{EXPLORE} and \qom{INSPECT\_3D} commands. 
  \item{Corrected 06-Jan-2022} The \sic{} command \texttt{DEFINE IMAGE} failed on large
FITS files. This prevented \qom{SHOW} and \qom{VIEW} to work directly from these files.
  \item{Corrected 18-Dec-2021} \qom{UV\_TIME} produced incorrect results on tables
with different weights per channel (e.g. those produced by \qomm{UV\_MERGE}{/MODE CONCATENATE}).
  \item{Corrected 13-Dec-2021} Remove occasional infinite loop in \qom{MAP\_CONTINUUM}
with method GAUSS (discovered 01-Dec-2021)
  \item{corrected 18-Nov-2021} \qom{UV\_REWEIGHT} syntax bug 
\end{itemize}

\subsection{Functional changes from previous versions}

Changes in Version 3.3
\begin{itemize}
\item{23-Mar-2022}  Introduce the \lang{IMAGER} language. Implement the \com{PIPELINE}
command there, and some miscellaneous (previously user-defined) commands like \com{TIPS}
and \com{POPUP}
\end{itemize}

Changes in Version 3.2
\begin{itemize}
\item{18-Mar-2022} Add the \comm{CLEAN}{/RESTART} capability
\item{10-Mar-2022} Improve dirty beam related commands behaviour: replace \sicvar{MAP\_BEAM\_STEP}
by \sicvar{BEAM\_STEP}, use \sicvar{BEAM\_SIZE} to specify beam shape.
\item{07-Mar-2022} Allow \qomm{WRITE BEAM}{/APPEND} in all cases
\item{08-Feb-2022} Implement the \sicvar{CLEAN\_STOP} syntax in \qom{CLEAN}
\item{10-Jan-2022} Implement the \com{LOAD} command in \viewer{}.
\item{07-Jan-2022} Implement \qom{SHOW}{PV} and improve transposed data display.
\item{06-Jan-2022} Allow direct \qom{READ} of FITS data cubes.
\item{03-Jan-2022} Improve syntax of \qom{COMBINE}
\item{17-Dec-2021} Improve \qomm{UV\_CHECK}{BEAM} and \com{FIT} commands.
\item{16-Dec-2021} Add the \qomm{UV\_MERGE}{/MODE CONCATENATE}
command to stitch adjacent or overlapping spectral windows. 
Imaging is in general only possible using \sicvar{BEAM\_STEP = 1}
after this, so far.
\item{13-Dec-2021} Implement a fast, reliable version of "statcont"
through the \qom{MAP\_CONTINUUM} command (run time $< 40$ secs 
for a 28 Gbyte data set on a 64-core machine)
\item{13-Dec-2021} Globally revised the Robust weighting scheme. Speed
up by huge amount for large (> 10 MegaVis) number of visibilities. 
UV data sorting not required anymore.
\item{08-Dec-2021} Change the CASA - GILDAS interface. Use pure-Python
scripts and put them in the \texttt{\$HOME/.casa} directory to have
a CASA-version independent solution.
\item{07-Dec-2021} A missing initialization was causing \qom{UV\_RESTORE}
to use the slow mode on some compiler versions.
\item{06-Dec-2021} Speed up (by a factor 5-10) the Natural weighting scheme
when there is only 1 channel. 
\item{19-Nov-2021}  Create the \viewer{} program, that only contains
the \lang{DISPLAY} language.
\item{19-Nov-2021} Expand the \qom{COMMAND ? Key} mechanism
to many commands.
\item{18-Nov-2021} Add the \qomm{STATISTIC}{/UPDATE} and\comm{FIT}{/JVM\_FACTOR}
commands
\end{itemize}

Changes in Version 3.0
\begin{itemize}
\item{31-Oct-2021} Introduce new \lang{DISPLAY} language. Move commands
\qom{CATALOG}, \qom{COLOR}, \qom{FIND}, \qom{EXPLORE}, \qom{INSPECT\_3D}, \qom{SHOW},
\qom{STATISTIC}, and \qom{VIEW} from their initial languages to this one.
\item Improvements in control variables of \qom{SHOW} and related commands (e.g.
allow unit of contours to be specified).
\end{itemize}

Changes up to Version 2.8 dated of Jan 31, 2021
\begin{itemize}
\item{17-Jun-2021} Add \qomm{SPECIFY}{FREQUENCIES} command for VLA data
\item{01-Jun-2021} Allow \texttt{MULTISCALE} Clean on Mosaics, better \qom{FIT} command.
\item{14-Dec-2020} \qom{SPECTRAL\_CLEAN} command
\item{31-Jan-2020} Add \qom{CCT\_CLEAN} command
\item{13-Nov-2020} Add \qom{MAP\_SMOOTH} command
\item{26-Oct-2020} Add \qom{UV\_SMOOTH} command 
\item{11-Sep-2020} Add \qomm{KEPLER}{/MASK} command for Mask creation
\item{03-Sep-2020} Better behaviour of command \qom{UV\_TIME}
\item{01-Sep-2020} Improve \qom{FIT} command for Mosaics
\end{itemize}

Changes since Version 2.5 of Feb 27th, 2020, and older ones.
\begin{itemize}
\item{13-Nov-2020} Speed-up the \qom{UV\_RESTORE} command.
\item{30-Jul-2020} Miscellaneous improvements in the \qom{KEPLER} command
\item{26-May-2020} Implementation of the \qom{UV\_DETECT} command,
  that encapsulates all actions needed for matched filtering in UV
  plane.
\item{14-May-2020} Proper implementation of the \qom{UV\_CORRRELATE} command,
  that performs matched filtering in the UV plane
\item{13-May-2020} \qom{MODEL} defines the \sicvar{UV\_MODEL} variable
\item{25-Mar-2020} Implementation of the \qom{KEPLER} command,
that allows optimal detection of spectral lines in Keplerian disks,
and estimates of radial profiles.
\item{19-Mar-2020} Proper implementation of the \qom{MODEL} command,
with the \qomm{MODEL}{/MODE} option and several channels.
\item{11-Mar-2020} Command EXPLORE added to language BUNDLES
\item{10-Mar-2020} CASA to GILDAS interface\\
  The \texttt{casagildas()} tool has been totally re-written in pure Python
  to avoid issues with incompatible releases of Fortran compilers and
  Python between CASA and GILDAS
\item{27-Feb-2020} 	\qom{UV\_SHORT} now allows to use images with non-circular
  beams as short spacings data. Such images can be, for example,
  an ACA image to be combined with ALMA data.
\item{24-Feb-2020} \texttt{imager-linedb.sic} script converted to 
Python 2 and 3 compatible syntax
\item{21-Feb-2020} \qom{UV\_MAP} was crashing on Mosaic in Robust 
  weighting. Linked to a missing (although optional !) argument 
  to call doweig, despite the interface was used.
\item{18-Feb-2020} 
	3D size was incorrectly set by \qom{UV\_MAP} on "huge" file (1200 x 1200 x 3840).
\item{14-Feb-2020} 
  Normalize message colours. 
\item{14-Feb-2020} Suppress blanking when not needed
\item{ 13-Feb-2020} Make \qom{UV\_MERGE} compliant with its Help: 
	allow to merge Line data sets in Continuum mode.
\item{10-Feb-2020} \qom{SLICE} command changes. \\
	The \texttt{SLICE} buffer had to be renamed to \texttt{SLICED}, as "slice()" is a 
  built-in Python method. The axis starts now from the closest point to 
  (0,0), leading to more intuitive slices.
\item{06-Feb-2020} \qom{MAP\_COMPRESS} syntax was incorrectly handled. 
	The \texttt{HELP MAP\_COMPRESS} is still unclear, however.
\item{18-Dec-2019}
  \qomm{VIEW}{CCT} optimized by coding the component compression after
    a \qom{MULTI}.
\item{17-Dec-2019} \qom{SELFCAL} optimization (was using slow mode
in \qom{UV\_RESTORE}  by default).
\item{27-Nov-2019} \qomm{UV\_CHECK}{/FILE} implemented.
\item{27-Nov-2019} \qomm{UV\_TIME}{/FILE} implemented.
\item{27-Nov-2019} \qomm{UV\_SHIFT}{/FILE} implemented.
\item{20-Nov-2019} Make sure \qom{UV\_PREVIEW} also works for 1 channel.
%
\end{itemize}

\subsection{Latest Bug corrections}
This section contains the list of bugs corrected since last documentation release.
\begin{enumerate}
\item{Corrected 28-Jun-2021} \qom{UV\_SHIFT} bug correction for "false" mosaics (ID and MOFF columns)
\item{Corrected 28-Jun-2021} \qom{UV\_SORT} bug correction for \qom{/FILE} option
\item{Discovered and Corrected 27-Oct-2021}  \qom{MAP\_INTEGRATE} lead to wrong units
and noise level.
\item{Discovered and Corrected 04-Apr-2021}  \qom{MULTISCALE} was using an incorrect convergence
strategy since years... Results were sub-optimal, and convergence was unduly slow.
\item{Discovered and Corrected 31-Jan-2021} \qomm{UV\_MAP}{/RANGE} was producing
a wrong velocity/frequency axis since 11-Dec-2020. (a line of code had disappeared).
\item{Discovered and Corrected 10-Dec-2020} \qom{MODEL} after \qom{UV\_FIT} was
ending with an undue error (bug present since 2-Jun-202
\item{corrected 8-Dec-2020} Mosaic offsets were not accounted for properly
since 19-Jun-2019.  The reason was a misplaced exclamation mark that
transformed a key instruction into a comment in the code file. 
Anomalous behaviour of the Mosaic mode were reported end of November, 
and a test case isolated on Dec 7 for analysis, leading a prompt correction. 
\item{corrected 26-Oct-2020} Several bugs in \qom{UV\_MERGE}
made it fail on some (usually large) data files, sometimes depending
on the order in which they were given (discovered 15-Oct-2020).
\item{corrected 14-Sep-2020} Incorrect transfer of self-calibration solution in \qom{APPLY}
and \qom{SELFCAL}{APPLY} on some UV data set from ALMA.
\item{corrected 11-Sep-2020} \qom{KEPLER} was off by 1 pixel.
\item{corrected 11-Sep-2020} Blanking was not updated in \qomm{MASK}{APPLY} 
\item 	\qomm{UV\_SHORT}{/REMOVE} does not properly delete the SHORT\% 
  variable in some cases, in particular if command \qom{XY\_SHORT} is (or has been)
  used (discovered 15-Feb-2020, still pending, difficult to reproduce).
\item{corrected 10-Jul-2020} \imager{} occasionally crashed after
a sequence of \qomm{UV\_MAP}{/CONT} and \qom{UV\_RESTORE} commands,
because of a map size mismatch. This size mismatch occured when the
baseline min-max of the UV data set are inconsistent with the UV data.
(discovered 07-Jul-2020).
\item{corrected 10-Jun-2020}   
  \qom{KEPLER} does not handle \sicvar{KEPLER\_X0} and \sicvar{KEPLER\_Y0} properly.
\item{corrected 20-May-2020}
  \qom{FITS} fails on large (300 GBytes..) UVFITS files. 
  (discovered 15-Feb-2020).
\item{corrected 19-Mar-2020} \qomm{MODEL}{/MINVAL} threshold was erroneously
transformed between Jy/beam and K.
\item{corrected 10-Mar-2020} \qom{MAP\_RESAMPLE} may crash on some combination of values
 (discovered 10-Mar-2020).
\item{corrected 10-Mar-2020} 
  \qom{VIEW} may fails the \sicvar{RANGE} is
non zero and the 3rd axis increment is negative.
\item{corrected 05-Mar-2020}
  \qom{UV\_MAP} fails after \qom{UV\_RESIDUAL} and \qomm{SELECT}{UV\_RESIDUAL}
if the initial UV data set was not sorted in XY.
\item{corrected 05-Mar-2020}
	\qom{MULTI} with non-zero value for \sicvar{CLEAN\_NITER} did not set up 
  properly the number of components (it finds 0). \qomm{SHOW}{CCT} and
  \qom{UV\_RESTORE} could not be used after.
\end{enumerate}
