2.1.1.0 calibrater.initweights

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calibrater.initweights - Function

2.1.1 Initialize MS weight info in various ways.

Description

This function initializes the MS weight info in various ways.

If wtmode=’ones’, SIGMA and WEIGHT will be initialized with 1.0, globally.

If wtmode=’nyq’ (the default), SIGMA and WEIGHT will be initialized according to bandwidth and integration time. This is the theoretically correct mode for raw normalized visibilities.

If wtmode=’sigma’, WEIGHT will be initialized according to the existing SIGMA column.

If mode=’weight’, WEIGHT_SPECTRUM will be initialized according to the existing WEIGHT column; dowtspec=T must be specified in this case.

For the above wtmodes, if dowtspec=T (or if the WEIGHT_SPECTRUM column already exists), the WEIGHT_SPECTRUM column will be initialized (uniformly in channel), in a manner consistent with the WEIGHT column. If the WEIGHT_SPECTRUM column does not exist, dowtsp=T will force its creation.

The follow modes should be used with extreme care: If wtmode=’delwtsp’, the WEIGHT_SPECTRUM column will be deleted (if it exists). If wtmode=’delsigsp’, the SIGMA_SPECTRUM column will be deleted (if it exists). Note that creation of SIGMA_SPECTRUM is not supported via this method.

Note that this method does not support any prior selection. Intialization of the weight information must currently be done globally or not at all. This is to maintain consistency.

Arguments


Inputs
wtmode	Initialization mode
	allowed:	string
	Default:	nyq
dowtsp	Initialize WEIGHT_SPECTRUM column
	allowed:	bool
	Default:	false
tsystable	Tsys calibration table to apply on the fly
	allowed:	string
	Default:
gainfield	Select a subset of calibrators from Tsys caltable
	allowed:	string
	Default:
interp	Interp type in time[,freq]. default==linear,linear
	allowed:	string
	Default:
spwmap	Spectral windows combinations to form for gaintables(s)
	allowed:	intArray
	Default:

Returns
bool

Example

cb.open(’ngc5921.ms’)
cb.initweights()
cb.close()

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