1.3.1.0 ms.fromfits

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ms.fromfits - Function

1.3.1 Create a measurement set from a uvfits file

Description

This function will convert a uvfits file to a measurement set table and then open the measurement set table. The newly created measurement set table will continue to exist after the tool has been closed.

Setting the lock argument to True will permanently lock the table preventing other processes from writing to the measurement set. Unless you expect this to happen, and want to prevent it, you should leave the lock argument at the default value which implies auto-locking.

Note that the variety of fits files that fromfits is able to interpret correctly is limited mostly to files similar to those produced by classic AIPS. In particular, it understands only binary table extensions for the antenna (AN), frequency (FQ) and source (SU) information and ignores other extensions.

This function returns True if it successfully attachs the ms tool to a newly created Measurement Set or False if something went wrong, like an error in a file name.

NOTE ON WEIGHTS

ms.fromfits() will generate a WEIGHT_SPECTRUM column in which it will fill the absolute value of the weight associated with each visibility in the uvfits file. Negative weights will have the associated FLAGs set to True. It will compute the associated WEIGHT value for that MS row to be the sum of the absolute values of the associated WEIGHT_SPECTRUM values.

Arguments


Inputs
msfile	Filename for the newly created measurement set
	allowed:	string
	Default:
fitsfile	uvfits file to read
	allowed:	string
	Default:
nomodify	open for read access only
	allowed:	bool
	Default:	true
lock	lock the table for exclusive use
	allowed:	bool
	Default:	false
obstype	specify the observation type: 0=standard, 1=fastmosaic, requiring small tiles in the measurement set
	allowed:	int
	Default:	0
host	host to start ms tool on (IGNORED!!!)
	allowed:	string
	Default:
forcenewserver	start a new server tool (IGNORED!!!)
	allowed:	bool
	Default:	false
antnamescheme	For VLA only, antenna name scheme, old style is just antenna number, new style prepends VA or EV
	allowed:	string
	Default:	old

Returns
bool

Example

ms.fromfits("3C273XC1.MS", "3C273XC1.fits")

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