2.1.1.0 autoflag.setdata

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autoflag.setdata - Function

2.1.1 Set the data parameters selection for subsequent processing
Description

This setup function selects which data are to be used subsequently. After invocation of setdata, only the selected subset of data are operated on.

Data can be selected by field ids, spectral window ids, channels, velocities. The selection is controlled by the mode argument:

fieldids: Selection in field ids.
spwids: Selection in spectral window ids.
channel: Selection in channels using the nchan, start and step arguments.
velocity: Selection in radio velocity, using the nchan, mstart and mstep arguments.

Spectral window ids must be specified for the channel and velocity modes.

For channel mode, the other fields have the following meaning:

nchan: is the number of output channels. It defaults to 1, or the number of input channels.
start: is the first channel from input dataset that is to be used. It defaults to 1 (i.e. first channel).
step: gives the increment between selected input channels.

The channels are centered on velocities: start, start+step, start+2*step, etc.

Examples for choosing the parameters for setdata.

af.setdata(mode=’fieldids’,fieldid=1);

af.setdata(mode=’spwids’,spwid=1);

af.setdata(mode=’spwids & fieldids’,spwid=1, fieldid=1);

af.setdata(mode=’channel’, nchan=64, start=1, step=1, spwid=1)

For velocity modes, the mstart and mstep are the start and step velocities as strings.

af.setdata(mode=’velocity’, nchan=64, mstart=’20km/s’, mstep=’-80m/s’, spwid=1)

For multi-spectral window selection, the data can be selected as follows

af.setdata(mode=’channel’, nchan=[20,30], start=[1,1], step=[1,1],
spwid=[1,2])

The above means that you would make a data selection of 20 channels (starting from 1 steping 1) from the first spectral window and 30 channels (starting from 1 steping 1) from the second spectral window.

Arguments


Inputs
mode		Type of processing: fieldids, spwids, channel or velocity
		allowed:	string
		Default:	spwids channel velocity fieldids none
nchan		Number of channels to select
		allowed:	intArray
		Default:	1
start		Start channels (0-relative)
		allowed:	intArray
		Default:	0
step		Step in channel number
		allowed:	intArray
		Default:	1
mstart	m/s	Start velocity (e.g. ’20Km/s’)
		allowed:	doublem/s
		Default:	0.0
mstep	m/s	Step in velocity (e.g. ’100m/s’
		allowed:	doublem/s
		Default:	0.0
spwid		Spectral Window Ids (0 relative) to select
		allowed:	intArray
		Default:
fieldid		Field Ids (0 relative) to select
		allowed:	intArray
		Default:
msselect		TQL select string applied as a logical ”and” with the other selections
		allowed:	string
		Default:
async		Run asynchronously in the background?
		allowed:	bool
		Default:	false

Returns
bool

Example

af:=autoflag(’testdata.ms’);
af.setdata(mode=’channel’,nchan=64,start=1,step=1,spwid=1,msselect=
’SCAN_NUMBER < 5’)
af.setselect(quack=[13,2],unflag=T);
af.run();
af.resetall();
af.summary();
af.setuvbin(thr=.01);
af.run();

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