1.3.1.0 ms.cvelfreqs

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ms.cvelfreqs - Function

1.3.1 calculate the transformed grid of the SPW obtained by combining a given set of SPWs (MS is not modified)

Description

Take the spectral grid of a given spectral window, tranform and regrid it as prescribed by the given grid parameters (same as in cvel and clean) and return the transformed values as a list. The MS is not modified. Useful for tests of gridding parameters before using them in cvel or clean.

Arguments


Inputs
spwids	The list of ids of the spectral windows from which the input grid is to be taken.
	allowed:	intArray
	Default:	0
fieldids	The list of ids of the fields which are selected (for observation time determination), default: all
	allowed:	intArray
	Default:	0
obstime	the observation time to assume, default: time of the first row of the MS =
	allowed:	string
	Default:
mode	”channel”, ”velocity”, ”frequency”, or ”channel_b”, default =
	allowed:	string
	Default:	channel
nchan	number of channels, default = all =
	allowed:	int
	Default:	-1
start	start channel, default =
	allowed:	any
	Default:	variant 0
width	new channel width, default =
	allowed:	any
	Default:	variant 1
phasec	phase center, default = first field in selection =
	allowed:	any
	Default:	variant
restfreq	rest frequency, default =
	allowed:	any
	Default:	variant 1.4GHz
outframe	LSRK, LSRD, BARY, GALACTO, LGROUP, CMB, GEO, TOPO, or SOURCE default = keep reference frame =
	allowed:	string
	Default:
veltype	radio or optical, default =
	allowed:	string
	Default:	radio
verbose	If true, create log output
	allowed:	bool
	Default:	true

Returns
doubleArray

Example

    ms.open(’my.ms’)
    ms.cvelfreqs(spwids=[1], mode=’channel’, nchan=20, start=2, width=3, outframe=’LSRK’)

    will take the grid of SPW 1 (i.e. the second in the SPW table), regrid it as in cvel
    with the given grid parameters and return the resulting channel centers as an array.
    The MS is not modified. See help cvel for more details on the grid parameters.

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