Table of Contents
ccdmom - moment or accumulate along an axis of an image
ccdmom
[parameter=value]
ccdmom takes special moments (in position,
or image intensity) along an axis of an image/cube. It can optionally also
accumulate along the selected axis.
The following parameters are
recognized in any order if the keyword is also given:
- in=
- Input image file.
No default.
- out=
- Output image file. No default.
- axis=
- Axis to take moment
along (1=x 2=y 3=z) [Default: 1]
- mom=
- Moment to take [-2,-1,0,1,2,3..]
Compute either the sum (0), mean (1)
, dispersion (2)
, or peak location
(3)
. Negative numbers also have a special meaning. -1 computes the average
intensity along the axis, where -2 computes the dispersion around the mean
value. [Default: 0].
- keep=t|f
- Boolean value if to keep the moment axis. If
you keep the axis (instead of compressing it), the values are replaced
with the computed moment. This can be useful if you want to subtract an
cube/image with the mean value along a certain axis. Only in this case (but
see also cumulative=t below) will the output image have the same shape
and dimension as the input image. [Default: f].
- cumulative=t|f
- Boolean value
if the values should accumulate instead along the selected axis. The mom=
keyword is ignored, and the input and output datasets will now have the
same shape and dimension. [Default: f]
pvtrace(1NEMO)
Cannot
compute straight moments, e.g. the 2nd moment along an axis, such as e.g. snapgrid
can do. This program only computes user friendly numbers (sum, mean, dispersion)
and gives special meaning to negative values of mom= and axis=.
src/image/misc/ccdmom.c
Peter Teuben
09-jun-95 V0.1 Created PJT
19-oct-95 V0.2 simple implementation of axis=3 PJT
12-dec-98 V0.3 finished mom=0,1,2 for all axes PJT
31-dec-98 V0.4 added keep= PJT
21-feb-01 V0.4a added mom=3, and fixed major bugs in computing moments PJT
25-mar-01 V0.5 added mom=-1 PJT
18-oct-05 V0.6 added mom=-2 and cumulative option PJT
Table of Contents