atcafiller

class atcafiller[source]

Filler for ATNF/ATCA RPFITS data

Methods Summary

`atcafiller`	This is used to construct an `atcafiller` tool for filling ATCA RPFITS data into a MeasurementSet
`fill`	This function does the actual filling of the data from rpfits format files to a MeasurementSet.
`opacities`	This function does the actual filling of the data from rpfits format files to a MeasurementSet.
`open`	This function does the actual filling of the data from rpfits format files to a MeasurementSet.
`select`	Select on various items, to load only a subset of the data present in the input file.

atcafiller()[source]: This is used to construct an atcafiller tool for filling ATCA RPFITS data into a MeasurementSet

fill()[source]: This function does the actual filling of the data from rpfits format files to a MeasurementSet. You may want to run select before fill, to reduce the amount of data you read in.

opacities(fghz='', tempk=300.0, humi=50.0, press=1010.0, height=200.0)[source]

This function does the actual filling of the data from rpfits format files to a MeasurementSet. You may want to run select before fill, to reduce the amount of data you read in.

Parameters

fghz (doubleVec='') - array of frequencies
tempk (float=300.0) - surface temperature in K
humi (float=50.0) - humidity in %
press (float=1010.0) - surface pressure in hPa
height (float=200.0) - observatory height in m

Returns

doubleVec

Examples

#
atf = atcafiller()
opac=atf.opacities([22.0,23.0],300.,50.,1013.,200.)
print opac
del atf

open(msname='', filenames='', options='')[source]

This function does the actual filling of the data from rpfits format files to a MeasurementSet. After the completion of the fill operation you should call the done method to avoid problems with incomplete flushing of the data to disk. You may want to run select before fill, to reduce the amount of data you read in.

In the filenames argument commas are not allowed because of the wildcard capability.

The options argument allows for special processing options during the filling process.

* birdie: remove self generated birdies in 128 MHz data by deleting every other channel and the edge channels * reweight: suppress ringing of interference spikes by reweighting the lag spectrum for minimum spectral sidelobe response * noxycorr: do not apply the xyphase correction using the noise cal xy phase measurements (use if you know there was a problem with the measurements) * compress: Compress the data, model, corrected data and imaging weight columns (may reduce dynamic range) * fastmosaic: Produce a MeasurementSet with small tiles to optimize I/O for observations with a large number of pointings and a short time (a few integrations) on each pointing. Failing to use this options for such data may cause very inefficient access, especially for continuum data (10-100 times slower) * hires: For data taken in binning mode: set the TIME_CENTROID column to the center of each bin (normally center of integration interval). The TIME column is unaffected. TIME_CENTROID will no longer be in time order for dual frequency mode. * noac : Do not load the autocorrelations

Parameters

msname (string='') - Filename for MeasurementSet to create
filenames (stringVec='') - Existing RPFITS files to read; wild cards accepted, don’t use commas
options (stringVec='') - Processing options: birdie, rfiflag, noxycorr, compress, fastmosaic, hires, reweight, noac

Returns

bool

Examples

#Specify that we want to load the data from files 1999-01-01\_0101.C999 and 
#1999-01-01\_0202.C999 in the directory /data/RPFITS into the MeasurementSet 
#myms.
atf = atcafiller()
atf.open('myms',
  "/data/RPFITS/1999-01-01_0101.C999 /data/RPFITS/1999-01-01_0202.C999",
  "birdie reweight")
atf.fill()
del atf
myms:=ms('myms')
myms.nrow()
#1204
myms.close()

select(firstscan=0, lastscan=9999, spw=[-1], lowfreq=0.1, highfreq=999.0, fields='', edge=8.0)[source]

Select on various items, to load only a subset of the data present in the input file. The default is to load everything. Note that the frequency selection using lowfreq and highfreq acts purely on center (reference) frequencies, channel selection is not available at this stage. Use freqchain to select the frequency chain (or IF) to load, specify either 1 or 2, the default of zero will load both. Use the fields parameter to specify a list of field names (sources) you want to load. For detailed selection of complex observations the last two parameters let you specify the required bandwidth (in whole MHz) and number of channels of the first frequency chain.

Parameters

firstscan (int=0) - First scan to read
lastscan (int=9999) - Last scan to read
spw (intVec=[-1]) - Select one or more spectralwindows , -1=all
lowfreq (double=0.1) - Lowest reference frequency to select
highfreq (double=999.0) - Highest reference frequency to select
fields (stringVec='') - List of field names (sources) to select
edge (float=8.0) - Percentage of edge channels to flag

Returns

bool

Examples

#Select scans 4 to 10 inclusive, frequency chain 1, all data with a
#reference frequency of more than 1.4 GHz.
atf = atcafiller()
atf.open('myms', '/data/RPFITS/1999-01-01_0101.C999')
atf.select(firstscan=4, lastscan=10, freqchain=1, lowfreq=1.4,edge=10)
atf.fill()
del atf