MAP_COMBINE

        [CLEAN\]MAP_COMBINE OutCube CODE In1 In2 [Off] [/FACTOR A1 A2]
      [/THRESHOLD T1 T2] [/BLANKING Bval]

    Combine in different ways two input images  (or  data  cubes).   MAP_COMBINE
    does  **NOT** request that the inputs have the same angular resolution, nei-
    ther the same unit. It is up to the user  to  avoid  combining  inconsistent
    quantities !...

    However,  MAP_COMBINE  attempts to handle input data in different units in a
    reasonably clever way, converting different  brightness  quantities  into  a
    single  unit.  Accordingly,  depending  on  the  requested  operation  CODE,
    MAP_COMBINE will return the results in different units.  In  practice,  this
    is  K for brightness (ADD), and no unit for Ratio (DIVIDE), Opacities (OPAC-
    ITY) or Spectral Index (INDEX).

      MAP_COMBINE also supports an "intuitive" , more mathematical syntax,
          MAP_COMBINE OutCube = [A1*]In1 Oper [A2*]In2 [Off]
      [/THRESHOLD T1 T2] [/BLANKING Bval]

    where Oper can be any of the values allowed for CODE, or one of the 4  stan-
    dard operators, +-/*, and scale factors are given in a natural way.

    CODE  is  the Operation Code: see HELP MAP_COMBINE CODE for details.  Off is
    an optional offset for the operation.

    OutCube can be a file name or an existing SIC Image variable.  The  distinc-
    tion  is made by the existence of a "." in the name.  If it is a file, it is
    created like the In1 Variable If it is a SIC Image variable, it  must  exist
    and match the shape of In1.

    In1 can be a file name or an existing SIC Image variable.

    In2  can be a file name or an existing Image variable.  The rank of In2 must
    be smaller than or equal to that of In1, and other dimensions must match.

    A1 and A2 are scale factors applied to In1 and In2 if needed (default 1).

    T1 and T2 are thresholds below which no result is computed (default none).