\subsection{In Version 3.7 and previous ones down to 3.0}
\begin{itemize}
 \item{\corrected 06-Sep-2023, \discovered 30-Jul-2023} \qom{PIPELINE} 
  was eating too much memory, leading to stall and crash. 
 \item{13-Jun-2023} Ensure the \qom{MODEL} command works correctly on Mosaics.
 \item{\corrected 10-Jun-2023, \discovered 15-Nov-2022} \qom{UV\_RESTORE} in Mosaic 
  mode was leading to
  subsequent crashes if the channel range is restricted by \qom{UV\_MAP} because
  a single beam cannot be applied to all channels.\\
  This is often the case for ALMA data, because of the shift implied by the
  Doppler correction when creating the UVFITS files. A work around is to 
  manually drop the edge channels by reading a coherent range of channels,
  and over-writing the UV data.
 \item{06-Jun-2023} Introduce the \com{LOG} command
 \item{03-Jun-2023} \qom{MAP\_{POLAR}{/ANGLE} } option to plot B-field directions.
 \item{25-May-2023} Bug correction in \qom{UV\_REWEIGHT} (wrong noise
 estimate if strong signal).
 \item{15-May-2023} Improve \qom{PRIMARY} command syntax.
 \item{03-May-2023} Add the \qom{PLAIT} command.
  \item{\corrected 25-Apr-2023}
  A missing initialization of \texttt{CHFLAG} (wrong size) was resulting in 
  flagged visibilites in \qom{/MODE CONT}.  
  \item{24-Mar-2023} Bug correction in \qom{MAP\_CONTINUUM}. \sicvar{SIZE}
  and \sicvar{CENTER} units not properly converted.
    \item{\corrected 08-Mar-2023} \qom{READ} was not closing properly FITS files when
  using the cache mechanism. 
  \item{\corrected 07-Mar-2023} \qom{MASK} was working extremely slowly on 2-D data sets.
  \item{\corrected 03-Mar-2023} \qom{UV\_SHIFT} was no longer working on degenerate 1-field Mosaic
    since introduction of the Sault mosaic mode (05-Jan-2023).
  \item{23-Feb-2023} Significant refurbishment of the plotting scripts
  and of their documentation and help tools. 
  \item{23-Feb-2023}
  Implementation of a \com{COMPARE} command that allows side-by-side
  comparison of two data cubes.
  \item{\corrected 22-Feb-2023} \qom{UV\_RESAMPLE, UV\_COMPRESS, UV\_HANNING, UV\_SMOOTH}
  were no longer handling correctly channels flagged by the \qom{UV\_FILTER} command
  since the introduction of the \qomm{UV\_FLAG}{/RESET} option on 03-May-2022.
  \item{17-Feb-2023} Complete the implementation of \qom{COMBINE} with automatic
  spectral resampling and spatial reprojection when needed.
  \item{17-Feb-2023} Support for \texttt{INDEX} operation in \qom{MAP\_COMBINE} 
  and \qom{COMBINE}, and for blanking values.
  \item{17-Feb-2023} Ensure \qom{MAP\_CONVOLVE} preserves flux when units
  are in Jy/beam and a proper beam size can be defined.
  \item{17-Feb-2023} Add support for blanking values in \qom{MAP\_RESAMPLE}
  \item{26-Jan-2023} Allow \qom{SLICE} to call the cursor, and \qom{SHOW}
  to display degenerate 2-D arrays as a 1-D plot.
  \item{\corrected 25-Jan-2023} The \qomm{SHOW}{UV-Like-Data} was crashing, working
  only for the current UV data. 
  \item{24-Jan-2023} Add the \qom{/DIRECTORY} option to commands
  \qom{SHOW}, \qom{VIEW}, \qom{EXPLORE}, \qom{INSPECT\_{3D}}.
  \item{20-Jan-2023} Add the \qom{MAP\_{CONVOLVE}} command to spatially
  smooth data cubes.
  \item{\corrected 20-Jan-2023} 
  \label{item:casa} The \texttt{casagildas()} tool provided by \imager{}
  to \casa{} to export MS in UVFITS file occasionally produced additional UVFITS files
  containing only part of the data for some spectral windows.  It also sometimes failed
  on specific spectral setups, where the same frequency occured for one narrow band and
  one wide band window.
  \item{05-Jan-2023} Complete implementation of the SAULT Mosaic construction
  method. Modified the \qom{MOSAIC} command for this.
  \item{15-Nov-2022} Add the \qom{/MODE} option to the \qom{PIPELINE}
	command, with 4 modes: \texttt{CONTINUUM, SPLIT, ALL} or \texttt{SURVEY}.
  \item{14-Nov-2022} Debug use of \sicvar{MAP\_CENTER} variable in various
	commands (for Mosaics, \qomm{UV\_SELF}, \qom{UV\_SHIFT}).
  \item{08-Nov-2022} Reorganize commands in languages:\qom{EXTRACT}, \qom{SLICE}
	 and \qom{POPUP} are now part of the \lang{Display} language 
  \item{\corrected 08-Sep-2022} Bug correction in \qom{EXTRACT} command.
  \item{05-Sep-2022} Add the \qom{/ASYMMETRIC} option of \qom{MAP\_SMOOTH}  and \qom{UV\_SMOOTH}
  \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{\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{22-Apr-2022} Improve \qom{UV\_PREVIEW} command
  \item{\corrected 13-Apr-2022} \qom{MAP\_COMBINE} and \qom{COMBINE} were not supporting
  big files.  
  \item{12-Apr-2022} Support for command \qom{STOKES} on internal buffers.
  \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.
\end{itemize}


\textbf{\large 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}

\textbf{\large 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{\corrected 09-Mar-2022} \qom{CCT\_MERGE} Concatenation was improper

\item{07-Mar-2022} Allow \qomm{WRITE BEAM}{/APPEND} in all cases
\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{08-Feb-2022} Implement the \sicvar{CLEAN\_STOP} syntax in \qom{CLEAN}
  \item{\corrected 18-Jan-2022, \discovered 17-Jan-2022 only} \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.
  \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{10-Jan-2022} Implement the \com{LOAD} command in \viewer{}.
  \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{07-Jan-2022} Implement \qom{SHOW}{PV} and improve transposed data display.
  \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{06-Jan-2022} Allow direct \qom{READ} of FITS data cubes.
\item{03-Jan-2022} Improve syntax of \qom{COMBINE}
  \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{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{\corrected 13-Dec-2021} Remove occasional infinite loop in \qom{MAP\_CONTINUUM}
with method GAUSS (discovered 01-Dec-2021)

\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{\corrected 18-Nov-2021} \qom{UV\_REWEIGHT} syntax bug 
\item{18-Nov-2021} Add the \qomm{STATISTIC}{/UPDATE} and\comm{FIT}{/JVM\_FACTOR}
commands
\end{itemize}


\textbf{\large 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).

\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{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.

\end{itemize}

\subsection{Older Bug corrections}
This section contains the list of bugs corrected much longer ago...

\textbf{\large Changes up to Version 2.8 dated of Jan 31, 2021}
\begin{itemize}
\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{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}

\textbf{\large Changes since Version 2.5 of Feb 27th, 2020, and older ones.}
\begin{itemize}
\item{Discovered and \corrected 10-Dec-2020} \qom{MODEL} after \qom{UV\_FIT} was
ending with an undue error (bug present since 2-Jun-2020)
\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{13-Nov-2020} Speed-up the \qom{UV\_RESTORE} command.
\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{30-Jul-2020} Miscellaneous improvements in the \qom{KEPLER} command  
\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} did not handle \sicvar{KEPLER\_X0} and \sicvar{KEPLER\_Y0} properly.
\item{\corrected 20-May-2020}
  \qom{FITS} failed on large (300 GBytes..) UVFITS files. 
  (discovered 15-Feb-2020).  
\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{\corrected 19-Mar-2020} \qomm{MODEL}{/MINVAL} threshold was erroneously
transformed between Jy/beam and K.
\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{\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.
\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}


