AIPS NRAO AIPS HELP file for RMSD in 31DEC21



As of Sat May 15 15:31:37 2021


RMSD: Creates an image of the local RMS around each pixel

INPUTS

INNAME                             Input image name (name)
INCLASS                            Input image name (class)
INSEQ             0.0     9999.0   Input image name (seq. #)
INDISK            0.0        9.0   Input image disk unit #
OUTNAME                            Output image name (name)
OUTCLASS                           Output image name (class)
OUTSEQ           -1.0     9999.0   Output image name (seq. #)
OUTDISK           0.0        9.0   Output image disk unit #.
BLC                                Bottom left corner of input
TRC                                Top right corner of input
IMSIZE                             Size of the box used to
                                   calculate rms, in pixels
                                   IMSIZE(2)=-1 => the circle
                                   of diameter=IMSIZE(1)is used
OPCODE                             'RMS ','MEAN','BLAN',
                                   'MAD ','MEDI'
                                   (see help), ' ' => 'RMS'
OPTYPE                             'ROBS', 'HIST'
                                   (see help), ' ' => 'ROBS'
SCALR1                             DataSCALR2                             >0 =>
                                    ABS(DATA) < SCALR2*RMS
                                    are replaced by blank
                                    (OPCODE='BLAN')
                                   <0 =>
                                    ABS(DATA) > ABS(SCALR2)*RMS
                                    are replaced by blank
                                    (OPCODE='BLAN')
                                   0 => no blanking
SCALR3                             Robust mean exclusion factor
                                   abs(data-mean)>SCALR3*rms
                                   are excluded.   0 -> 3.
FLUX                               Data with RMS>FLUX
                                    are replaced by blank
                                    (OPCODE='BLAN')
                                   0 => no blanking
XINC                               Increment at X to calculate
                                   RMS, in pixels
YINC                               Increment at Y to calculate
                                   RMS, in pixels
                                   The intermediate points are
                                   calculated by interpolation

HELP SECTION

RMSD
Task:  Creates an image of the local RMS around each pixel over all
       planes of an image cube.  The rms is calculated for each pixel
       based on the data in a box surrounding the pixel. The size of the
       box is controlled by the user (adverb IMSIZE).  RMS is calculated
       in a multi-iteration (30) "robust" basis.  In the first iteration
       the RMS is calculated using all points in the box.  After that,
       points which differ from the mean by more than SCALR3*RMS are
       excluded from the consideration for the next iteration.
       The iteration process is terminated if none point is excluded.

       The input image should have the standard sequence of axes with
       two celestial axes followed by a spectral axis.
Adverbs:
  INNAME.....Input image name (name).     Standard defaults.
  INCLASS....Input image name (class).    Standard defaults.
  INSEQ......Input image name (seq. #).   0 => highest.
  INDISK.....Disk drive # of input image. 0 => any.
  OUTNAME....Output image name (name).    Standard defaults.
  OUTCLASS...Output image name (class)    Standard defaults.
  OUTSEQ.....Output image name (seq. #).  0 => highest unique.
  OUTDISK....Disk drive # of output image.  0 => highest
  BLC........Bottom left corner in input image of desired
             subimage.  Default is entire image.
  TRC........Top right corner in input image of desired
             subimage.  Default is entire image.
  IMSIZE.....Size of the box used to calculate rms, in pixels
             IMSIZE(2)=-1 => a circle of diameter = IMSIZE(1) is used,
             instead of a rectangle IMSIZE(1) x IMSIZE(2)
  OPCODE.....'RMS ' => creates map of RMSes calculated for each pixel
                using the data inside of the given box surrounding
                the pixel.
             'MEAN' => creates map of MEANes calculated for each pixel
                using the data inside of the given box surrounding
                the pixel.
             'BLAN' => the image value is replaced by BLANK under
                control of adverbs SCALR1 and SCALR2 and calculated
                RMS.  This option prepares the image cube to be ready
                for other tasks (XMOM for example) that require cutoff
                the 'bad' points on the basis of rms calculated in the
                vicinity of each image point.
             'MAD ' => creates image of the median absolute deviation or
                MAD = 1.4826 * median ( abs (x - median(x)) )
                where the factor converts to an "rms equivalent"
                ignores OPTYPE and SCALRn
             'MEDI' => creates image of the median in the box centered
                on the pixel; ignores OPTYPE and SCALRn
             '    ' => 'RMS '
  OPTYPE.....Concept of RMS' calculation
             'ROBS' => The far away points are rejected at the multi
                       iteration process
             'HIST' => The histogram concept is used. Data for histogram
                       are at the range -+ 1.5sigma. The histogram is
                       calculated at 16 intervals with center at the
                       mean value
  SCALR1.....In OPCODE='BLAN' only, data values below SCALR1*RMS are
             replaced by BLANK.
  SCALR2.....In OPCODE='BLAN' only, when SCALR2 > 0.0, data values less
               in absolute value than RMS*SCALR2 are replaced by blank.
             When SCALR2 < 0.0, data values greater in absolute value
               than ABS(SCALR2) are replaced by blank.
             When SCALR2=0, no replacement by blank
  SCALR3.....In robust determination of the mean/rms, values differing
             from the current mean by more than SCALR3 * current rms are
             excluded from the computation of mean/rms in this
             iteration.    0 -> 3.
  FLUX.......Data with RMS>FLUX are replaced by blank (OPCODE='BLAN')
             FLUX is in Jy/beam
             0 => no replacement by blank

  Replacement by blank is carried out (OPCODE='BLAN')
  if 'SCALR1' .OR. 'SCALR2' .OR. 'FLUX'

  XINC.......Increment at X to calculate RMS, in pixels

  YINC.......Increment at Y to calculate RMS, in pixels

  The task RMS requires a lot of computing time. XINC, YINC are invented
  to weaken the computing time problem. The RMS is calculated every
  XINC, YINC at the X,Y directions. The RMS of intermediate points are
  estimated by interpolation. The computing time should be reduced
  by the factor XINC*YINC

  Programmer Leonia Kogan

EXPLAIN SECTION







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