Displays statistical information from a measurement set, or from a measurement set selection
This task returns statistical information about data in a measurement
set.
The following values are computed: mean value, sum of values,
sum of squared values, median, median absolute deviation, quartile,
minimum, maximum, variance, standard deviation, and root mean square.
The following axes are supported: uvw, flag, weight, sigma, antenna1,
antenna2, feed1, feed2, field_id, array_id, data_desc_id, flag_row,
interval, scan, scan_number, time, weight_spectrum, amp, amplitude,
phase, real, imag, imaginary, and uvrange.
Optionally, the statistical information can be computed based only
on a given subset of the measurement set.
Note: If the MS consists of inhomogeneous data, for example several
spectral windows each having a different number of channels, it may be
necessary to use selection parameters to select a homogeneous subset of
the MS, e.g. spw='2'.
Keyword arguments:
vis --- Name of input visibility file
default: '', example: vis='my.ms'
axis -- Which data to analyze.
default: 'amplitude'
axis='phase'
axis='imag'
axis='scan_number'
axis='flag'
The phase of a complex number is in radians in the range [-pi; pi[.
datacolumn -- Which data column to use for complex data.
default: 'data'
datacolumn='data'
datacolumn='corrected'
datacolumn='model'
useflags -- Take MS flags into account?
default: True
useflag=False
useflag=True
If useflags=False, flagged values are included in the statistics.
If useflags=True, any flagged values are not used in the statistics.
spw -- Select data based on spectral window and channels
default: '' (all); example: spw='1'
spw='<2' #spectral windows less than 2
spw='>1' #spectral windows greater than 1
spw='0:0~10' # first 10 channels from spw 0
spw='0:0~5;56~60' # multiple separated channel chunks.
field -- Select data based on field id(s) or name(s)
default: '' (all); example: field='1'
field='0~2' # field ids inclusive from 0 to 2
field='3C*' # all field names starting with 3C
selectdata -- Other data selection parameters
default: True
antenna -- Select data based on baseline
default: '' (all); example: antenna='5&6' baseline 5-6
antenna='5&6;7&8' #baseline 5-6 and 7-8
antenna='5' # all baselines with antenna 5
antenna='5,6' # all baselines with antennas 5 and 6
correlation -- Correlation types
default: '' (all);
example: correlation='RR LL'
uvrange -- Select data within uvrange (default units meters)
default: '' (all); example:
uvrange='0~1000klambda'; uvrange from 0-1000 kilo-lambda
uvrange='>4klambda';uvranges greater than 4 kilo-lambda
uvrange='0~1000km'; uvrange in kilometers
timerange -- Select data based on time range:
default = '' (all); example,
timerange = 'YYYY/MM/DD/hh:mm:ss~YYYY/MM/DD/hh:mm:ss'
Note: YYYY/MM/DD can be dropped as needed:
timerange='09:14:0~09:54:0' # this time range
timerange='09:44:00' # data within one integration of time
timerange='>10:24:00' # data after this time
timerange='09:44:00+00:13:00' #data 13 minutes after time
scan -- Select data based on scan number
default: '' (all); example: scan='>3'
array -- Selection based on the antenna array
observation -- Selection by observation ID(s).
default: '' (all); example: observation='1~3'
1.8.0