1 Language
    ALMA        : Joint deconvolution of ALMA and ACA dirty images
    CLARK       : Deconvolve a dirty image using the CLARK clean algorithm
    DUMP        : Dump the control parameters of the deconvolution algorithms
    FIT         : Fit the dirty beam
    HOGBOM      : Deconvolve a dirty image using the basic clean algorithm
    LOAD        : Load an image or cube into the W SIC variable
    MOSAIC      : Toggle the mosaic mode
    MULTI       : Deconvolve a dirty image using the MULTI‐SCALE Clean
    MRC         : Deconvolve a dirty image using the MULTI‐RESOLUTION Clean
    MX          : Iteratively image and deconvolve a dirty image
    READ        : Read the input files in internal buffers
    SDI         : Deconvolve a dirty image using the Steer‐Dewdney‐Ito Clean
    STATISTIC   : Compute statistics on image
    SUPPORT     : Define the support used to search clean components
    UV_FLAG     : Interactively flag UV data
    UV_MAP      : Build the dirty image and beam from a UV table
    UV_RESAMPLE : Resample (in Velocity) the UV data
    UV_RESTORE  : Restore a Clean image from UV data and Clean Components
    UV_SHOW     : Display UV data
    UV_SORT     : Sort and Transpose UV data for plotting
    UV_STAT     : Gives beam sizes and noise properties as a function of
                   tapering or robust weighting parameter
    WIPE        : Image and deconvolve a uv table using the wipe algorithm
    WRITE       : Save internal buffers into output files

1 ALMA
        [CLEAN\]ALMA [FirstPlane LastPlane] [/PLOT Clean|Residu] [/FLUX Fmin
    Fmax] [/QUERY] [/NOISE] [/METHOD]

    Joint deconvolution methods specific to ALMA+ACA observations.

    The ALMA simulator can be accessed either by  typing  "@  alma"  at  the
    prompt or from the MAPPING main menu.

1 CLARK
        [CLEAN\]CLARK  [FirstPlane  LastPlane]  [/PLOT  Clean|Residu] [/FLUX
    Fmin Fmax] [/QUERY]

    A Major‐Minor cycles CLEAN method, originally developed by  B.Clark,  in
    which  clean components are selected using a limited beam patch, and de‐
    convolved through Fourier transform at each major cycle. In mosaic  mode
    (See  command  MOSAIC), a mosaic clean is performed. Rings and/or strips
    may appear on extended sources.  Faster than the Hogbom method for  sin‐
    gle  fields  but  maybe  slower  for mosaics. The strategy to search for
    CLEAN components in CLARK does not work properly when the secondary side
    lobes are too large (e.g. larger than 0.3).

    Clean  the  specified  plane interval (default: planes between variables
    FIRST and LAST). If option /PLOT is given, a display  of  the  CLEAN  or
    RESIDUAL  map  will be shown at each major cycle, depending on the argu‐
    ment (default: Residual). The user will  be  prompted  for  continuation
    when  the /QUERY option is present. The cumulative, already cleaned flux
    is displayed in real time in an additional window while cleaning goes on
    when  the  /FLUX  option  is present. Parameters of the /FLUX option are
    then used to give the flux limits for this display.

    The user can control the algorithm  through  SIC  variables.  Values  of
    those variables can be checked through either "INPUT UV_MAP|CLEAN|UVALL"
    or "EXAMINE
     VARIABLE". New values can be given using "LET VARIABLE value". For ease
    of  use, and whenever it is possible, a sensible value of each parameter
    will automatically be computed from the context if the value of the cor‐
    responding  variable  is  set  to its default value, i.e. zero value and
    empty string. A few variables are initialized to "reasonable" values.

    GAIN       [       ] Loop gain
    NITER      [       ] Maximum number of clean components
    FRES       [      %] Maximum value of residual (Fraction of peak)
    ARES       [Jy/Beam] Maximum value of residual (Absolute)
    BLC        [  pixel] Bottom left corner of cleaning box
    TRC        [  pixel] Top right corner of cleaning box
    POSITIVE   [       ] Minimum number of positive components at start
    KEEP       [       ] Keep cleaning after convergence
    MAJOR      [ arcsec] Clean beam major axis
    MINOR      [ arcsec] Clean beam minor axis
    ANGLE      [ degree] Position angle of clean beam
    BEAM_PATCH [  pixel] Size of cleaning beam ** not clear **

2 GAIN

    This is the gain of the subtraction loop.  It should typically be chosen
    in the range 0.05 and 0.3.  Higher values give faster convergence, while
    lower values give a better restitution of the extended structure. A sen‐
    sible default is 0.2.

2 NITER

    This is the maximum number of components the program will accept to sub‐
    tract.  Once it has been reached, the  program  starts  the  restoration
    phase.

2 FRES

    This  is the minimal fraction of the peak flux in the dirty map that the
    program  will  consider  as  significant.   Alternatively,  an  absolute
    threshold can be specified using ARES.  Once this level has been reached
    the program stops subtracting, and starts the restoration  phase.   This
    parameter is normalized to 1 (neither in % nor in db).  It should usual‐
    ly be of the order of magnitude of the inverse of the  expected  dynamic
    range of the intensity.

2 ARES

    This is the minimal flux in the dirty map that the program will consider
    as significant.  Alternatively, the threshold  can  be  specified  as  a
    fraction  of the peak flux using FRES.  Once this level has been reached
    the program stops subtracting, and starts the  restoration  phase.   The
    unit for this parameter is the map unit (Typically Jy/Beam).  The param‐
    eter should usually be of the order of magnitude of the  expected  noise
    in the clean map.

2 BLC

    These  are  the  (pixel)  coordinates  of  the Bottom Left Corner of the
    cleaning box.  The actual cleaning support will be the  intersection  of
    the specified window with the inner quarter of the map and with any user
    defined polygon.

2 TRC

    These are the (pixel) coordinates of the Top Right Corner of the  clean‐
    ing  box.   The  actual  cleaning window will be the intersection of the
    specified window with the inner quarter of the map and with any user de‐
    fined polygon.

2 POSITIVE

    The  minimum  number of positive components before negative ones are se‐
    lected.

2 KEEP

    This is a logical flag to keep cleaning after an approximate convergence
    has been reached.  It should usually be set to .TRUE., except may be for
    the SIMPLE method.

2 MAJOR

    This is the major axis  (FWHP)  in  user  coordinates  of  the  Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 MINOR

    This is the minor axis  (FWHP)  in  user  coordinates  of  the  Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 ANGLE

    This is the position angle (from North towards East, i.e. anticlockwise)
    of  the  major  axis of the Gaussian restoring beam (in degrees).  If 0,
    the program will fit a Gaussian to the dirty beam. We strongly  discour‐
    age to change the default value of 0.

2 BEAM_PATCH

    The  dirty  beam  patch to be used for the minor cycles in CLARK and MRC
    method.  It should be large enough to avoid doing too many major cycles,
    but  has  practically  no  influence on the result.  This size should be
    specified in pixel units.  Reasonable values are between  N/8  and  N/4,
    where N is the number of map pixels in the same dimension.  If set to N,
    the CLARK algorithm becomes identical to the SIMPLE algorithm.

1 DUMP
        [CLEAN\]DUMP [U]

    Dump on screen the control parameters of the different CLEAN  deconvolu‐
    tion algorithms, mainly for debugging purpose. "DUMP U" dumps the param‐
    eters as input by the user while "DUMP" dumps the parameters really used
    and/or modified by the deconvolution algorithm.

1 FIT
        [CLEAN\]FIT [Field]

    Fit  the  dirty  beam to obtain the clean beam parameters.  This is done
    automatically by all CLEAN algorithm when needed. Clean beam  parameters
    can also be specified by the users, by setting the variables MAJOR_AXIS,
    MINOR_AXIS and ANGLE to values other than their default values  (0,0,0).
    In  this case, no automatic fit will be performed.  We strongly discour‐
    age the use of those variables.

    In mosaic mode, you can specify on which field the fit has to  be  made,
    using the first argument.

1 HOGBOM
        [CLEAN\]HOGBOM [FirstPlane LastPlane] [/FLUX Fmin Fmax]

    The  simplest CLEAN algorithm, originally developed by Hogbom. In mosaic
    mode (See command MOSAIC), a mosaic clean is performed.   Rings  and  or
    strips  may  appear  on  extended sources. It is slower than CLARK for a
    single field but maybe faster for a  mosaic.  It  is  extremely  robust.
    Cleaning can be interrupted by pressing C at any time.

    Clean  the  specified  plane interval (default: Planes between variables
    FIRST and LAST). The cumulative, already cleaned flux  is  displayed  in
    real  time in an additional window while cleaning goes on when the /FLUX
    option is present. Parameters of the /FLUX option are then used to  give
    the flux limits for this display.

    The  user  can  control  the  algorithm through SIC variables. Values of
    those variables can be checked through either "INPUT UV_MAP|CLEAN|UVALL"
    or "EXAMINE
     VARIABLE". New values can be given using "LET VARIABLE value". For ease
    of use, and whenever it is possible, a sensible value of each  parameter
    will automatically be computed from the context if the value of the cor‐
    responding variable is set to its default value,  i.e.  zero  value  and
    empty string. A few variables are initialized to "reasonable" values.

    GAIN       [       ] Loop gain
    NITER      [       ] Maximum number of clean components
    FRES       [      %] Maximum value of residual (Fraction of peak)
    ARES       [Jy/Beam] Maximum value of residual (Absolute)
    BLC        [  pixel] Bottom left corner of cleaning box
    TRC        [  pixel] Top right corner of cleaning box
    POSITIVE   [       ] Minimum number of positive components at start
    KEEP       [       ] Keep cleaning after convergence
    MAJOR      [ arcsec] Clean beam major axis
    MINOR      [ arcsec] Clean beam minor axis
    ANGLE      [ degree] Position angle of clean beam
    BEAM_PATCH [  pixel] Size of cleaning beam ** not clear **

2 GAIN

    This is the gain of the subtraction loop.  It should typically be chosen
    in the range 0.05 and 0.3.  Higher values give faster convergence, while
    lower values give a better restitution of the extended structure. A sen‐
    sible default is 0.2.

2 NITER

    This is the maximum number of components the program will accept to sub‐
    tract.   Once  it  has  been reached, the program starts the restoration
    phase.

2 FRES

    This is the minimal fraction of the peak flux in the dirty map that  the
    program  will  consider  as  significant.   Alternatively,  an  absolute
    threshold can be specified using ARES.  Once this level has been reached
    the  program  stops subtracting, and starts the restoration phase.  This
    parameter is normalized to 1 (neither in % nor in db).  It should usual‐
    ly  be  of the order of magnitude of the inverse of the expected dynamic
    range of the intensity.

2 ARES

    This is the minimal flux in the dirty map that the program will consider
    as  significant.   Alternatively,  the  threshold  can be specified as a
    fraction of the peak flux using FRES.  Once this level has been  reached
    the  program  stops  subtracting, and starts the restoration phase.  The
    unit for this parameter is the map unit (Typically Jy/Beam).  The param‐
    eter  should  usually be of the order of magnitude of the expected noise
    in the clean map.

2 BLC

    These are the (pixel) coordinates of  the  Bottom  Left  Corner  of  the
    cleaning  box.   The actual cleaning support will be the intersection of
    the specified window with the inner quarter of the map and with any user
    defined polygon.

2 TRC

    These  are the (pixel) coordinates of the Top Right Corner of the clean‐
    ing box.  The actual cleaning window will be  the  intersection  of  the
    specified window with the inner quarter of the map and with any user de‐
    fined polygon.

2 POSITIVE

    The minimum number of positive components before negative ones  are  se‐
    lected.

2 KEEP

    This is a logical flag to keep cleaning after an approximate convergence
    has been reached.  It should usually be set to .TRUE., except may be for
    the SIMPLE method.

2 MAJOR

    This  is  the  major  axis  (FWHP)  in  user coordinates of the Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 MINOR

    This  is  the  minor  axis  (FWHP)  in  user coordinates of the Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 ANGLE

    This is the position angle (from North towards East, i.e. anticlockwise)
    of the major axis of the Gaussian restoring beam (in  degrees).   If  0,
    the  program will fit a Gaussian to the dirty beam. We strongly discour‐
    age to change the default value of 0.

2 BEAM_PATCH

    The dirty beam patch to be used for the minor cycles in  CLARK  and  MRC
    method.  It should be large enough to avoid doing too many major cycles,
    but has practically no influence on the result.   This  size  should  be
    specified  in  pixel  units.  Reasonable values are between N/8 and N/4,
    where N is the number of map pixels in the same dimension.  If set to N,
    the CLARK algorithm becomes identical to the SIMPLE algorithm.

1 LOAD
        [CLEAN\]LOAD Buffer

    Load  the internal Buffer (CLEAN, DIRTY, RESIDUAL and BEAM) into the SIC
    variable named W for future used with standard GREG  commands.  Used  in
    particular by the procedure
            GO PLOT Variable [First [Last]]
    which  will  plot  all  channels of the specified buffer. A shortcuts is
    given through
            SHOW Variable [First [Last]]
    First (default: 0) and Last (default: First) are optional arguments  in‐
    dicating  the  first  and last channel to be displayed. If not specified
    the variables FIRST and LAST are used.

    Most aspects of the display are controlled through the  same  SIC  vari‐
    ables as the ones used by the "GO BIT|MAP|LMV" commands. Detailed infor‐
    mation about those variables is found through the "INPUT LMV" command.

1 MOSAIC
        [CLEAN\]MOSAIC [On|Off]

    Turn on or off the mosaic mode (default: On). Note that a  READ  PRIMARY
    command  automatically  switches  on the mosaic mode. The program prompt
    changes to inform the user.

1 MRC
        [CLEAN\]MRC [FirstPlane LastPlane] [/PLOT Clean|Residu] [/FLUX  Fmin
    Fmax] [/QUERY]

    Perform  a  Multi‐Resolution CLEAN on the current dirty image.  MRC does
    not support mosaics for theoretical reasons.

    Clean the specified plane interval (default:  planes  between  variables
    FIRST  and  LAST).  If  option /PLOT is given, a display of the CLEAN or
    RESIDUAL map will be shown at each major cycle, depending on  the  argu‐
    ment  (default:  Residual).  The  user will be prompted for continuation
    when the /QUERY option is present. The cumulative, already cleaned  flux
    is displayed in real time in an additional window while cleaning goes on
    when the /FLUX option is present. Parameters of  the  /FLUX  option  are
    then  used to give the flux limits for this display. A summary plot with
    the Difference, Smooth, and total CLEANed maps is also displayed.

    The user can control the algorithm  through  SIC  variables.  Values  of
    those variables can be checked through either "INPUT UV_MAP|CLEAN|UVALL"
    or "EXAMINE
     VARIABLE". New values can be given using "LET VARIABLE value". For ease
    of  use, and whenever it is possible, a sensible value of each parameter
    will automatically be computed from the context if the value of the cor‐
    responding  variable  is  set  to its default value, i.e. zero value and
    empty string. A few variables are initialized to "reasonable" values.

    GAIN       [       ] Loop gain
    NITER      [       ] Maximum number of clean components
    FRES       [      %] Maximum value of residual (Fraction of peak)
    ARES       [Jy/Beam] Maximum value of residual (Absolute)
    BLC        [  pixel] Bottom left corner of cleaning box
    TRC        [  pixel] Top right corner of cleaning box
    POSITIVE   [       ] Minimum number of positive components at start
    KEEP       [       ] Keep cleaning after convergence
    MAJOR      [ arcsec] Clean beam major axis
    MINOR      [ arcsec] Clean beam minor axis
    ANGLE      [ degree] Position angle of clean beam
    BEAM_PATCH [  pixel] Size of cleaning beam ** not clear **
    RATIO      [       ] Smoothing factor

2 GAIN

    This is the gain of the subtraction loop.  It should typically be chosen
    in the range 0.05 and 0.3.  Higher values give faster convergence, while
    lower values give a better restitution of the extended structure. A sen‐
    sible default is 0.2.

2 NITER

    This is the maximum number of components the program will accept to sub‐
    tract.  Once it has been reached, the  program  starts  the  restoration
    phase.

2 FRES

    This  is the minimal fraction of the peak flux in the dirty map that the
    program  will  consider  as  significant.   Alternatively,  an  absolute
    threshold can be specified using ARES.  Once this level has been reached
    the program stops subtracting, and starts the restoration  phase.   This
    parameter is normalized to 1 (neither in % nor in db).  It should usual‐
    ly be of the order of magnitude of the inverse of the  expected  dynamic
    range of the intensity.

2 ARES

    This is the minimal flux in the dirty map that the program will consider
    as significant.  Alternatively, the threshold  can  be  specified  as  a
    fraction  of the peak flux using FRES.  Once this level has been reached
    the program stops subtracting, and starts the  restoration  phase.   The
    unit for this parameter is the map unit (Typically Jy/Beam).  The param‐
    eter should usually be of the order of magnitude of the  expected  noise
    in the clean map.

2 BLC

    These  are  the  (pixel)  coordinates  of  the Bottom Left Corner of the
    cleaning box.  The actual cleaning support will be the  intersection  of
    the specified window with the inner quarter of the map and with any user
    defined polygon.

2 TRC

    These are the (pixel) coordinates of the Top Right Corner of the  clean‐
    ing  box.   The  actual  cleaning window will be the intersection of the
    specified window with the inner quarter of the map and with any user de‐
    fined polygon.

2 POSITIVE

    The  minimum  number of positive components before negative ones are se‐
    lected.

2 KEEP

    This is a logical flag to keep cleaning after an approximate convergence
    has been reached.  It should usually be set to .TRUE., except may be for
    the SIMPLE method.

2 MAJOR

    This is the major axis  (FWHP)  in  user  coordinates  of  the  Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 MINOR

    This is the minor axis  (FWHP)  in  user  coordinates  of  the  Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 ANGLE

    This is the position angle (from North towards East, i.e. anticlockwise)
    of  the  major  axis of the Gaussian restoring beam (in degrees).  If 0,
    the program will fit a Gaussian to the dirty beam. We strongly  discour‐
    age to change the default value of 0.

2 BEAM_PATCH

    The  dirty  beam  patch to be used for the minor cycles in CLARK and MRC
    method.  It should be large enough to avoid doing too many major cycles,
    but  has  practically  no  influence on the result.  This size should be
    specified in pixel units.  Reasonable values are between  N/8  and  N/4,
    where N is the number of map pixels in the same dimension.  If set to N,
    the CLARK algorithm becomes identical to the SIMPLE algorithm.

2 RATIO

    Used smoothing factor, which must be a power of 2. The default is  esti‐
    mated from the image size.

1 MULTI
        [CLEAN\]MULTI [FirstPlane LastPlane] [/FLUX Fmin Fmax]

    Multiscale CLEAN algorithm.

    Clean  the  specified  plane interval (default: Planes between variables
    FIRST and LAST). The cumulative, already cleaned flux  is  displayed  in
    real  time in an additional window while cleaning goes on when the /FLUX
    option is present. Parameters of the /FLUX option are then used to  give
    the flux limits for this display.

    MULTI does not yet work on mosaics.

    The  user  can  control  the  algorithm through SIC variables. Values of
    those variables can be checked through either "INPUT UV_MAP|CLEAN|UVALL"
    or "EXAMINE
     VARIABLE". New values can be given using "LET VARIABLE value". For ease
    of use, and whenever it is possible, a sensible value of each  parameter
    will automatically be computed from the context if the value of the cor‐
    responding variable is set to its default value,  i.e.  zero  value  and
    empty string. A few variables are initialized to "reasonable" values.

    GAIN       [       ] Loop gain
    NITER      [       ] Maximum number of clean components
    FRES       [      %] Maximum value of residual (Fraction of peak)
    ARES       [Jy/Beam] Maximum value of residual (Absolute)
    BLC        [  pixel] Bottom left corner of cleaning box
    TRC        [  pixel] Top right corner of cleaning box
    POSITIVE   [       ] Minimum number of positive components at start
    KEEP       [       ] Keep cleaning after convergence
    MAJOR      [ arcsec] Clean beam major axis
    MINOR      [ arcsec] Clean beam minor axis
    ANGLE      [ degree] Position angle of clean beam
    BEAM_PATCH [  pixel] Size of cleaning beam ** not clear **

2 GAIN

    This is the gain of the subtraction loop.  It should typically be chosen
    in the range 0.05 and 0.3.  Higher values give faster convergence, while
    lower values give a better restitution of the extended structure. A sen‐
    sible default is 0.2.

2 NITER

    This is the maximum number of components the program will accept to sub‐
    tract.   Once  it  has  been reached, the program starts the restoration
    phase.

2 FRES

    This is the minimal fraction of the peak flux in the dirty map that  the
    program  will  consider  as  significant.   Alternatively,  an  absolute
    threshold can be specified using ARES.  Once this level has been reached
    the  program  stops subtracting, and starts the restoration phase.  This
    parameter is normalized to 1 (neither in % nor in db).  It should usual‐
    ly  be  of the order of magnitude of the inverse of the expected dynamic
    range of the intensity.

2 ARES

    This is the minimal flux in the dirty map that the program will consider
    as  significant.   Alternatively,  the  threshold  can be specified as a
    fraction of the peak flux using FRES.  Once this level has been  reached
    the  program  stops  subtracting, and starts the restoration phase.  The
    unit for this parameter is the map unit (Typically Jy/Beam).  The param‐
    eter  should  usually be of the order of magnitude of the expected noise
    in the clean map.

2 BLC

    These are the (pixel) coordinates of  the  Bottom  Left  Corner  of  the
    cleaning  box.   The actual cleaning support will be the intersection of
    the specified window with the inner quarter of the map and with any user
    defined polygon.

2 TRC

    These  are the (pixel) coordinates of the Top Right Corner of the clean‐
    ing box.  The actual cleaning window will be  the  intersection  of  the
    specified window with the inner quarter of the map and with any user de‐
    fined polygon.

2 POSITIVE

    The minimum number of positive components before negative ones  are  se‐
    lected.

2 KEEP

    This is a logical flag to keep cleaning after an approximate convergence
    has been reached.  It should usually be set to .TRUE., except may be for
    the SIMPLE method.

2 MAJOR

    This  is  the  major  axis  (FWHP)  in  user coordinates of the Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 MINOR

    This  is  the  minor  axis  (FWHP)  in  user coordinates of the Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 ANGLE

    This is the position angle (from North towards East, i.e. anticlockwise)
    of the major axis of the Gaussian restoring beam (in  degrees).   If  0,
    the  program will fit a Gaussian to the dirty beam. We strongly discour‐
    age to change the default value of 0.

2 BEAM_PATCH

    The dirty beam patch to be used for the minor cycles in  CLARK  and  MRC
    method.  It should be large enough to avoid doing too many major cycles,
    but has practically no influence on the result.   This  size  should  be
    specified  in  pixel  units.  Reasonable values are between N/8 and N/4,
    where N is the number of map pixels in the same dimension.  If set to N,
    the CLARK algorithm becomes identical to the SIMPLE algorithm.

1 MX
        [CLEAN\]MX  [FirstPlane  LastPlane] [/PLOT Clean|Residu] [/FLUX Fmin
    Fmax] [/QUERY]

    Make and deconvolve maps starting from a UV table.  It  combines  UV_MAP
    and CLEAN in a single step.

    The mapping process is identical to UV_MAP.  It makes a map from UV data
    by griding the UV data using a convolving function, and then Fast Fouri‐
    er  Transforming the individual channels.  However, MX always produces a
    single beam for all channels, thus neglecting frequency  change  between
    channels.   MX  enables to shift the map center and rotate the image, by
    shifting the phase tracking center and rotating the  UV  coordinates  of
    the input UV table.

    The  CLEAN  algorithm is similar to the CLARK method, but with major cy‐
    cles operating directly on the ungridded UV table rather than in the im‐
    age  plane. Accordingly, aliasing affects only of the residuals, not the
    clean components. It is thus more accurate but also slower than CLARK as
    it  asks  for the gridding step at each major cycle.  MX also shares the
    same limitation as CLARK on large sidelobes.

    The user can control the algorithm  through  SIC  variables.  Values  of
    those variables can be checked through either "INPUT UV_MAP|CLEAN|UVALL"
    or "EXAMINE
     VARIABLE". New values can be given using "LET VARIABLE value". For ease
    of  use, and whenever it is possible, a sensible value of each parameter
    will automatically be computed from the context if the value of the cor‐
    responding  variable  is  set  to its default value, i.e. zero value and
    empty string. A few variables are initialized to "reasonable" values.

    NAME        [       ]  Label of the dirty image and beam plots
    UV_TAPER    [m,m,deg]  UV‐apodization by convolution with a Gaussian
    WEIGHT_MODE [       ]  Weighting mode (NA|UN)
    UV_CELL     [m, ??  ]  UV cell size and threshold for Robust weighting
    MAP_SIZE    [ pixels]  Map size in pixels
    MAP_CELL    [ arcsec]  Map cell size
    MCOL        [       ]  First and Last channel to map
    WCOL        [       ]  Channel from which the weights are taken
    CONVOLUTION [       ]  Convolution function (5)
    UV_SHIFT    [       ]  Change the map phase center or map orientation?
    MAP_RA      [       ]  RA of map phase center
    MAP_DEC     [       ]  Dec of map phase center
    MAP_ANGLE   [    deg]  Map position angle
    GAIN       [       ] Loop gain
    NITER      [       ] Maximum number of clean components
    FRES       [      %] Maximum value of residual (Fraction of peak)
    ARES       [Jy/Beam] Maximum value of residual (Absolute)
    BLC        [  pixel] Bottom left corner of cleaning box
    TRC        [  pixel] Top right corner of cleaning box
    POSITIVE   [       ] Minimum number of positive components at start
    KEEP       [       ] Keep cleaning after convergence
    MAJOR      [ arcsec] Clean beam major axis
    MINOR      [ arcsec] Clean beam minor axis
    ANGLE      [ degree] Position angle of clean beam
    BEAM_PATCH [  pixel] Size of cleaning beam ** not clear **
2 NAME

    The name to be printed on the right side of the dirty  image  and  dirty
    beam plots (with extensions .LMV and .BEAM).

2 UV_TAPER

    Parameters  of the tapering function (Gaussian): major axis at 1/e level
    [m], minor axis at 1/e level [m], and position angle [deg].

2 WEIGHT_MODE

    Weighting mode: Natural (optimum in  terms  of  sensitivity)  or  robust
    (usually  lower sidelobes) weighting. Use LET WEIGHT_MODE NA for natural
    or LET WEIGHT_MODE UN for robust weighting.

    The actual weighting methods implemented are Natural and Robust  weight‐
    ing. Robust weighting gives the natural weight to UV cells whose natural
    weight is lower than a given threshold.  In  contrast,  if  the  natural
    weight  of  the UV cell is larger than this threshold, the weight is set
    to this (uniform) threshold. The UV cell size and  the  threshold  value
    are contained in the UV_CELL variable.

2 UV_CELL

    UV_CELL[1]  :  UV  cell size for robust weighting [m].  Should be of the
    order of half the dish diameter (7.5 m for PdBI), or smaller.

    UV_CELL[2] : Threshold for robust weighting. Default value is 1. 0 means
    natural weighting and infinite would mean uniform weighting. Use UV_STAT
    WEIGHT to choose an educated value.

2 MAP_SIZE

    Number of pixels in X and Y. It should preferentially be a power of two,
    (although    this   is   not   strictly   required)   to   fasten   FFT.
    MAP_SIZE*MAP_CELL should be at least twice the size of the field‐of‐view
    (primary  beam  size  for  a single field). Enter 0,0 to let the command
    find a sensible map size.

2 MAP_CELL

    The map pixel size [arcsec]. It is recommended to use  identical  values
    in  X  and Y.  A sampling of at least 3 pixel per beam is recommended to
    ease the deconvolution. Enter 0,0 to let the task find the best values.

2 MCOL

    First and Last channel to image.  Values  of  0  mean  imaging  all  the
    planes.

2 WCOL

    The  channel from which the weight should be taken.  WCOL set to 0 means
    using the central channel.

2 CONVOLUTION

    Select the desired convolution function for gridding  in  the  UV  plane
    Choices are
            0    Default (currently 5)
            1    Boxcar
            2    Gaussian
            3    Sin(x)/x
            4    Gaussian * Sin(x)/x
            5    Spheroidal
    Spheroidal  functions  is  the optimal choice. So we strongly discourage
    use of any other convolution function.

2 UV_SHIFT

    Logical variable indicating whether map center (i.e. phase tracking cen‐
    ter) or orientation should be changed.

2 MAP_RA

    New Right Ascension of map phase center. Used only if UV_SHIFT is YES.

2 MAP_DEC

    New Declination of map phase center. Used only if UV_SHIFT is YES.

2 MAP_ANGLE

    Position  Angle of the direction which will become the apparent North in
    the map. Used only if UV_SHIFT is YES.

2 GAIN

    This is the gain of the subtraction loop.  It should typically be chosen
    in the range 0.05 and 0.3.  Higher values give faster convergence, while
    lower values give a better restitution of the extended structure. A sen‐
    sible default is 0.2.

2 NITER

    This is the maximum number of components the program will accept to sub‐
    tract.  Once it has been reached, the  program  starts  the  restoration
    phase.

2 FRES

    This  is the minimal fraction of the peak flux in the dirty map that the
    program  will  consider  as  significant.   Alternatively,  an  absolute
    threshold can be specified using ARES.  Once this level has been reached
    the program stops subtracting, and starts the restoration  phase.   This
    parameter is normalized to 1 (neither in % nor in db).  It should usual‐
    ly be of the order of magnitude of the inverse of the  expected  dynamic
    range of the intensity.

2 ARES

    This is the minimal flux in the dirty map that the program will consider
    as significant.  Alternatively, the threshold  can  be  specified  as  a
    fraction  of the peak flux using FRES.  Once this level has been reached
    the program stops subtracting, and starts the  restoration  phase.   The
    unit for this parameter is the map unit (Typically Jy/Beam).  The param‐
    eter should usually be of the order of magnitude of the  expected  noise
    in the clean map.

2 BLC

    These  are  the  (pixel)  coordinates  of  the Bottom Left Corner of the
    cleaning box.  The actual cleaning support will be the  intersection  of
    the specified window with the inner quarter of the map and with any user
    defined polygon.

2 TRC

    These are the (pixel) coordinates of the Top Right Corner of the  clean‐
    ing  box.   The  actual  cleaning window will be the intersection of the
    specified window with the inner quarter of the map and with any user de‐
    fined polygon.

2 POSITIVE

    The  minimum  number of positive components before negative ones are se‐
    lected.

2 KEEP

    This is a logical flag to keep cleaning after an approximate convergence
    has been reached.  It should usually be set to .TRUE., except may be for
    the SIMPLE method.

2 MAJOR

    This is the major axis  (FWHP)  in  user  coordinates  of  the  Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 MINOR

    This is the minor axis  (FWHP)  in  user  coordinates  of  the  Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 ANGLE

    This is the position angle (from North towards East, i.e. anticlockwise)
    of  the  major  axis of the Gaussian restoring beam (in degrees).  If 0,
    the program will fit a Gaussian to the dirty beam. We strongly  discour‐
    age to change the default value of 0.

2 BEAM_PATCH

    The  dirty  beam  patch to be used for the minor cycles in CLARK and MRC
    method.  It should be large enough to avoid doing too many major cycles,
    but  has  practically  no  influence on the result.  This size should be
    specified in pixel units.  Reasonable values are between  N/8  and  N/4,
    where N is the number of map pixels in the same dimension.  If set to N,
    the CLARK algorithm becomes identical to the SIMPLE algorithm.

1 READ
        [CLEAN\]READ Buffer File [/PLANE First Last] [/COMPACT]

    Read the specified internal buffer (UV,  BEAM,  PRIMARY,  DIRTY,  CLEAN,
    MASK)  from  input File. Default extension are .uvt, .beam, .lobe, .lmv,
    .lmv‐clean and /PLANE (valid also for UV tables). The /COMPACT option is
    used to load the ACA‐specific internal buffer used in the ALMA joint de‐
    convolution method.

1 SDI
        [CLEAN\]SDI [FirstPlane LastPlane] [/PLOT Clean|Residu] [/FLUX  Fmin
    Fmax] [/QUERY]

    Perform a Steer‐Dewdney‐Ito CLEAN. This clean method selects an ensemble
    of clean components and remove them at once using FFTs.  It  works  best
    for  extended  sources  and  UV coverages with short spacings. In such a
    case, it may avoid the "ringing" features which appear using  the  CLARK
    or  HOGBOM  techniques.  In  mosaic  mode (see command MOSAIC), a mosaic
    clean is performed.

    Clean the specified plane interval (default:  planes  between  variables
    FIRST  and  LAST).  If  option /PLOT is given, a display of the CLEAN or
    RESIDUAL map will be shown at each major cycle, depending on  the  argu‐
    ment  (default:  Residual).  The  user will be prompted for continuation
    when the /QUERY option is present. The cumulative, already cleaned  flux
    is displayed in real time in an additional window while cleaning goes on
    when the /FLUX option is present. Parameters of  the  /FLUX  option  are
    then used to give the flux limits for this display.

    The  user  can  control  the  algorithm through SIC variables. Values of
    those variables can be checked through either "INPUT UV_MAP|CLEAN|UVALL"
    or "EXAMINE
     VARIABLE". New values can be given using "LET VARIABLE value". For ease
    of use, and whenever it is possible, a sensible value of each  parameter
    will automatically be computed from the context if the value of the cor‐
    responding variable is set to its default value,  i.e.  zero  value  and
    empty string. A few variables are initialized to "reasonable" values.
    GAIN       [       ] Loop gain
    NITER      [       ] Maximum number of clean components
    FRES       [      %] Maximum value of residual (Fraction of peak)
    ARES       [Jy/Beam] Maximum value of residual (Absolute)
    BLC        [  pixel] Bottom left corner of cleaning box
    TRC        [  pixel] Top right corner of cleaning box
    POSITIVE   [       ] Minimum number of positive components at start
    KEEP       [       ] Keep cleaning after convergence
    MAJOR      [ arcsec] Clean beam major axis
    MINOR      [ arcsec] Clean beam minor axis
    ANGLE      [ degree] Position angle of clean beam
    BEAM_PATCH [  pixel] Size of cleaning beam ** not clear **

2 GAIN

    This is the gain of the subtraction loop.  It should typically be chosen
    in the range 0.05 and 0.3.  Higher values give faster convergence, while
    lower values give a better restitution of the extended structure. A sen‐
    sible default is 0.2.

2 NITER

    This is the maximum number of components the program will accept to sub‐
    tract.   Once  it  has  been reached, the program starts the restoration
    phase.

2 FRES

    This is the minimal fraction of the peak flux in the dirty map that  the
    program  will  consider  as  significant.   Alternatively,  an  absolute
    threshold can be specified using ARES.  Once this level has been reached
    the  program  stops subtracting, and starts the restoration phase.  This
    parameter is normalized to 1 (neither in % nor in db).  It should usual‐
    ly  be  of the order of magnitude of the inverse of the expected dynamic
    range of the intensity.

2 ARES

    This is the minimal flux in the dirty map that the program will consider
    as  significant.   Alternatively,  the  threshold  can be specified as a
    fraction of the peak flux using FRES.  Once this level has been  reached
    the  program  stops  subtracting, and starts the restoration phase.  The
    unit for this parameter is the map unit (Typically Jy/Beam).  The param‐
    eter  should  usually be of the order of magnitude of the expected noise
    in the clean map.

2 BLC

    These are the (pixel) coordinates of  the  Bottom  Left  Corner  of  the
    cleaning  box.   The actual cleaning support will be the intersection of
    the specified window with the inner quarter of the map and with any user
    defined polygon.

2 TRC

    These  are the (pixel) coordinates of the Top Right Corner of the clean‐
    ing box.  The actual cleaning window will be  the  intersection  of  the
    specified window with the inner quarter of the map and with any user de‐
    fined polygon.

2 POSITIVE

    The minimum number of positive components before negative ones  are  se‐
    lected.

2 KEEP

    This is a logical flag to keep cleaning after an approximate convergence
    has been reached.  It should usually be set to .TRUE., except may be for
    the SIMPLE method.

2 MAJOR

    This  is  the  major  axis  (FWHP)  in  user coordinates of the Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 MINOR

    This  is  the  minor  axis  (FWHP)  in  user coordinates of the Gaussian
    restoring beam. If 0, the program will fit a Gaussian to the dirty beam.
    We strongly discourage to change the default value of 0.

2 ANGLE

    This is the position angle (from North towards East, i.e. anticlockwise)
    of the major axis of the Gaussian restoring beam (in  degrees).   If  0,
    the  program will fit a Gaussian to the dirty beam. We strongly discour‐
    age to change the default value of 0.

2 BEAM_PATCH

    The dirty beam patch to be used for the minor cycles in  CLARK  and  MRC
    method.  It should be large enough to avoid doing too many major cycles,
    but has practically no influence on the result.   This  size  should  be
    specified  in  pixel  units.  Reasonable values are between N/8 and N/4,
    where N is the number of map pixels in the same dimension.  If set to N,
    the CLARK algorithm becomes identical to the SIMPLE algorithm.

1 STATISTIC
        [CLEAN\]STATISTIC [Clean|Dirty|Residu] [Plane] [/WHOLE]

    Compute some basic statistics (min, max, mean, rms,...) on the specified
    buffer (default: Clean) and plane (default: variable FIRST). The current
    polygon  (see  command  SUPPORT) is used to define the area on which the
    pixels are to be taken  into  account,  except  when  option  /WHOLE  is
    present: The whole image is then considered.

1 SUPPORT
        [CLEAN\]SUPPORT [Polygon] [/CURSOR] [/PLOT] [/MASK] [/RESET]

    Define the support inside which to search for CLEAN components. The sup‐
    port can be defined through a mask or a polygon, depending  on  the  op‐
    tions selected.

    Withouth  /MASK  or /RESET option, SUPPORT calls command POLYGON of GREG
    to load a polygon. A polygon stored in a  file can be load  as  support.
    The /PLOT option can then be used to plot it.

2 /CURSOR
        [CLEAN\]SUPPORT  /CURSOR           With option /CURSOR, it calls the
    interactive cursor to define the polygon summits.  Type any key to go to
    next  summit,  D  to  correct the last one and type E to end the polygon
    definition. The last polygon side will then appear. The polygon  defini‐
    tion may be aborted by typing Q. For X11 displays, you may use the mouse
    buttons for the commands.  The left mouse button  draws  a  vertex,  the
    middle  mouse button deletes the last vertex, and the right mouse button
    ends the polygon definition.

2 /RESET
        [CLEAN\]SUPPORT /RESET

    Reset any support to default.

2 /MASK
        [CLEAN\]SUPPORT /MASK

    Use the mask defined by READ MASK as the clean support.  This  does  not
    suppress the current polygon: it can be re‐instated by SUPPORT /PLOT.
     READ MASK performs an implicit SUPPORT /MASK command.

2 /PLOT
        [CLEAN\]SUPPORT [filename] /PLOT

    Plot  the  current  (or  specified) polygon and use it to define the the
    clean support. This does not suppress the current mask: it can be re‐in‐
    stated by SUPPORT /MASK.

1 UV_FLAG
        [CLEAN\]UV_FLAG [/RESET]

    Display  UV  data  and calls the cursor to interactively select a region
    where UV data will be flagged (sign of weight is reversed).  The  /RESET
    option  is  used to unflag the data. Subsequent mapping with UV_MAP will
    ignore flagged data. UV data flagged using command UV_FLAG can be  saved
    on  file with command WRITE UV File. Detailed information about the dis‐
    play control of the UV data may be found in the UV_SHOW help.

    The user can control the algorithm through variables.  Values  of  those
    variables  can  be  checked  using "EXAMINE VARIABLE". New values can be
    given using "LET VARIABLE value".

    DATE_START  [    ] The date of the first data to be flagged
    UT_START    [    ] The UT time of the first data to be flagged
    DATE_END    [    ] The date of the last data to be flagged
    UT_END      [    ] The time of the last data to be flagged
    BASELINE    [    ] Baseline to flagged
    CHANNEL     [    ] Channel range to be flagged/unflagged
    FLAG        [    ] Flag or unflag the specified time range

2 DATE_START

    The date (DD‐MMM‐YYYY) of the first data to be flagged.

2 UT_START

    The UT time (hh:mm:ss.ss) of the first data to be flagged.

2 DATE_END

    The date (DD‐MMM‐YYYY) of the last data to be flagged.

2 UT_END

    The time (hh:mm:ss.ss) of the last data to be flagged.

2 BASELINE

    Baseline (ALL, 12, 13, 23, ...) to flagged.

2 FLAG

    Flag (T) or unflag (F) the specified time range.

2 CHANNEL

    Channel range to be flagged/unflagged.

1 UV_MAP
        [CLEAN\]UV_MAP

    Compute a dirty map and beam from a UV data.  UV  data  must  have  been
    loaded from a UV table by command "READ UV File".

    The  user  can  control  the  algorithm through SIC variables. Values of
    those variables can be checked through either "INPUT UV_MAP|CLEAN|UVALL"
    or "EXAMINE
     VARIABLE". New values can be given using "LET VARIABLE value". For ease
    of use, and whenever it is possible, a sensible value of each  parameter
    will automatically be computed from the context if the value of the cor‐
    responding variable is set to its default value,  i.e.  zero  value  and
    empty string. A few variables are initialized to "reasonable" values.

    NAME        [       ]  Label of the dirty image and beam plots
    UV_TAPER    [m,m,deg]  UV‐apodization by convolution with a Gaussian
    WEIGHT_MODE [       ]  Weighting mode (NA|UN)
    UV_CELL     [m, ??  ]  UV cell size and threshold for Robust weighting
    MAP_SIZE    [ pixels]  Map size in pixels
    MAP_CELL    [ arcsec]  Map cell size
    MCOL        [       ]  First and Last channel to map
    WCOL        [       ]  Channel from which the weights are taken
    CONVOLUTION [       ]  Convolution function (5)
    UV_SHIFT    [       ]  Change the map phase center or map orientation?
    MAP_RA      [       ]  RA of map phase center
    MAP_DEC     [       ]  Dec of map phase center
    MAP_ANGLE   [    deg]  Map position angle
2 NAME

    The  name  to  be printed on the right side of the dirty image and dirty
    beam plots (with extensions .LMV and .BEAM).

2 UV_TAPER

    Parameters of the tapering function (Gaussian): major axis at 1/e  level
    [m], minor axis at 1/e level [m], and position angle [deg].

2 WEIGHT_MODE

    Weighting  mode:  Natural  (optimum  in  terms of sensitivity) or robust
    (usually lower sidelobes) weighting. Use LET WEIGHT_MODE NA for  natural
    or LET WEIGHT_MODE UN for robust weighting.

    The  actual weighting methods implemented are Natural and Robust weight‐
    ing. Robust weighting gives the natural weight to UV cells whose natural
    weight  is  lower  than  a  given threshold. In contrast, if the natural
    weight of the UV cell is larger than this threshold, the weight  is  set
    to  this  (uniform)  threshold. The UV cell size and the threshold value
    are contained in the UV_CELL variable.

2 UV_CELL

    UV_CELL[1] : UV cell size for robust weighting [m].  Should  be  of  the
    order of half the dish diameter (7.5 m for PdBI), or smaller.

    UV_CELL[2] : Threshold for robust weighting. Default value is 1. 0 means
    natural weighting and infinite would mean uniform weighting. Use UV_STAT
    WEIGHT to choose an educated value.

2 MAP_SIZE

    Number of pixels in X and Y. It should preferentially be a power of two,
    (although   this   is   not   strictly   required)   to   fasten    FFT.
    MAP_SIZE*MAP_CELL should be at least twice the size of the field‐of‐view
    (primary beam size for a single field). Enter 0,0  to  let  the  command
    find a sensible map size.

2 MAP_CELL

    The  map  pixel size [arcsec]. It is recommended to use identical values
    in X and Y.  A sampling of at least 3 pixel per beam is  recommended  to
    ease the deconvolution. Enter 0,0 to let the task find the best values.

2 MCOL

    First  and  Last  channel  to  image.  Values  of 0 mean imaging all the
    planes.

2 WCOL

    The channel from which the weight should be taken.  WCOL set to 0  means
    using the central channel.

2 CONVOLUTION

    Select the desired convolution function for gridding  in  the  UV  plane
    Choices are
            0    Default (currently 5)
            1    Boxcar
            2    Gaussian
            3    Sin(x)/x
            4    Gaussian * Sin(x)/x
            5    Spheroidal
    Spheroidal functions is the optimal choice. So  we  strongly  discourage
    use of any other convolution function.

2 UV_SHIFT

    Logical variable indicating whether map center (i.e. phase tracking cen‐
    ter) or orientation should be changed.

2 MAP_RA

    New Right Ascension of map phase center. Used only if UV_SHIFT is YES.

2 MAP_DEC

    New Declination of map phase center. Used only if UV_SHIFT is YES.

2 MAP_ANGLE

    Position Angle of the direction which will become the apparent North  in
    the map. Used only if UV_SHIFT is YES.

1 UV_RESAMPLE
        [CLEAN\]UV_RESAMPLE [Nc Ref Val Inc]

    Resample  the  UV  data loaded by READ UV on a different velocity scale.
    All UV commands work on the "Resampled" UV table.
         Nc   new number of channels
         Ref  New reference pixel
         Val  New velocity at reference pixel
         Inc  Velocity increment
    The "Resampled" UV table is equal to the original one after  a  READ  UV
    command,  or after a UV_RESAMPLE command without arguments. ** not clear
    **

1 UV_RESTORE
        [CLEAN\]UV_RESTORE

    Create a Clean image from the UV data set and the Clean Component  list.
    The  Clean  Components  are  subtracted  from the UV data set, and these
    residuals are gridded and Fourier transformed to  compute  the  Residual
    image. This Residual image is added to the Gaussian beam convolved image
    of the sum of Clean components.

    This command can be used after HOGBOM or CLARK, but not yet  MRC,  MULTI
    or SDI.  The results are similar to those of MX, since only the residual
    are aliased.

1 UV_SHOW
        [CLEAN\]UV_SHOW

    Display UV data currently in the internal buffer, i.e. loaded by command
    READ UV File and optionally resampled by UV_RESAMPLE. Control parameters
    are available as SIC variables. Use command INPUT UV_SHOW to check them.
    Flagged UV data will appear in a different color.

1 UV_SORT
        [CLEAN\]UV_SORT TIME|BASE

    Sort and transpose the UV data set, loaded by command READ UV File.  Or‐
    der is either TIME for Time‐Baseline ordering,  BASE  for  Baseline‐Time
    ordering.  The sorted UV data is then available in variable UVS for fur‐
    ther plotting. ** Is this done in the internal buffer? **

1 UV_STAT
        [CLEAN\]UV_STAT TAPER|WEIGHT|CELL [Step Start]

    Predict the synthesized beam, expected noise level, and recommended pix‐
    el  size  for  different values of tapering distance or robust weighting
    threshold or uv cell size. UV_STAT allows the astronomer to  select  the
    best  weighting  parameters  according to its personal trade off between
    angular resolution and sensitivity.

    For TAPER, beam sizes and noise level (in flux and brightness)  will  be
    computed  for  9 different tapers (from Start to Start*Step^9).  Default
    value for Step is sqrt(2), Default value for Start is  50  m.  Weighting
    mode,  UV  cell  size  and  "robust"  parameter  are taken from variable
    UV_CELL.

    For WEIGHT, beam sizes and noise level (in flux and brightness) will  be
    computed  for  9  different "robust" weighting parameters (from Start to
    Start*Step^9). Default value for Step is sqrt(10), and default value for
    Start  is  derived to center the "robust" parameter values around 1.  UV
    cell size is taken from variable UV_CELL[1], and  Taper  is  taken  from
    variable UV_TAPER.

    For  CELL,  beam  sizes  and noise level are computed for 9 different UV
    cell sizes. This version is still under development.

1 WIPE
        [CLEAN\]WIPE [INFO | APER | BEAM | SOLVE [/INTERACTIVE] | ERROR]

    WIPE is a deterministic deconvolution method using CLEAN (Hogbom,  Clark
    ?  **NR** ) as a starting point. WIPE applies a regularization principle
    and provides error analysis on the deconvolution process.  A strategy is
    defined  in WIPE to build automatically the effective support of the ob‐
    ject under observation.  However a starting support (analog to  a  Clean
    Support) can be defined to restrict the search.

    WIPE  INFO  displays information about the UV table relevant to the WIPE
    deconvolution method. WIPE APER fit an ellipse to the observed UV tracks
    to  define  the region where the experimental frequency coverage will be
    interpolated by the WIPE deconvolution method. In other words,  this  is
    the  definition  of  the frequency coverage to be synthesized. WIPE BEAM
    computes the neat and the dirty beams for the WIPE deconvolution method.
    WIPE  SOLVE starts the WIPE deconvolution method. The control parameters
    are
        MAP_SIZE     [pixels] Number of pixels of the mapped image
        MAP_CELL     [arcsec] Size of map cell in arcsec
        WIPE%PROC    [      ] Channel number to process in uv file
        WCOL         [      ] Channel to use for weighting
        WEIGHT_MODE  [      ] Weighting mode (NA|UN)
        WIPE%APER    [      ] Axis of the ellipse to interpolate

    A typical session using wipe is
        read uv file.uvt
        let map_size 256
        let map_cell 0.15
        uv_map
        show beam
        show dirty
        polygon
        let wipe%nclean 100
        let wipe%gain 0.2
        let wipe%cycle 50
        let wipe%proc 0
        wipe info
        wipe aper
        wipe beam
        wipe solve
        show residual
        show neat
        wipe error
        write dirty file
        write beam file
        write neat file

2 MAP_SIZE

    Number of pixels in each direction of the image.

2 MAP_CELL

    Size of pixel in each direction [arcsec].

2 WIPE%PROC

    Channel number to be processed. If 0 is selected, WIPE SOLVE will  auto‐
    matically set the default to 1.

2 WCOL

    The column number of the input UV table to be used to get the visibility
    weights.

2 WEIGHT_MODE

    Two weighting modes are available. The ’UN’ or uniform weight  mode  at‐
    tributes the same contribution to each weight. Whereas the ’NA’ or natu‐
    ral mode takes into account the local density of visibilities.

2 WIPE%APER

    Multiplicative factors to apply on major and minor axis of  the  default
    ellipse characterizing the aperture to be synthesized in the uv plane.

1 WRITE
        [CLEAN\]WRITE Buffer File

    WRITE  the  specified buffer (UV, BEAM, PRIMARY, DIRTY, CLEAN, RESIDUAL,
    SUPPORT, CCT, NEAT, NMR) onto a File. Default extension are  uvt,  beam,
    lmv, lobe, lmv‐clean, lmv‐res, pol, cct, lmv‐neat, lmv‐nmr.

1 ENDOFHELP



