Examples
Example 1
This is one of the simplest examples. To fit and remove a Chebyshev polynomial function (default is 5th order) from the data 'sd_data.ms', using only spectral window 0, and fitting channels 100-800 and 1200-2000 (to avoid, for example, band-pass roll off at the edges, and perhaps an emission line that might occur over channels 800-1200).
sdbaseline(infile='sd_data.ms', spw='0:100~800;1200~2000',blfunc='chebyshev',outfile='sd_data.ms.bl',overwrite =True)
Example 2
This example shows fitting and subtracting a sinusoidal baseline. To fit and remove a sinusoid from the data 'sd_data.ms', using spectral window 0 and scan number 0. Wave numbers of sinusoids are set autmatically in the fft method.
sdbaseline(infile='sd_data.ms',spw='0',scan='0',blfunc='sinusoid',applyfft=True,fftmethod='fft',outfile='sd_data.ms.bl',overwrite=True)
Example 3
In this example, the user specifies different fitting parameters per spectrum, using blfunc='variable' and specifying the fit parameters using a text file.
sdbaseline(infile='sd_data.ms',blfunc='variable',blparam='blparam.txt',outfile='sd_data.ms.bl',overwrite =True)
Here is the text file "blparam.txt" used in the above example.
#row,pol,mask,clipniter,clipthresh,use_linefinder,thresh,Ledge,Redge,avg_limit,blfunc,order,npiece,nwave
0,0,100~750;1250~1900,0,3.,false,0.,0,0,0,chebyshev,2,0,[]
0,1,,0,3.,false,0.,0,0,0,chebyshev,0,0,[]
1,0,0~500;1500~2000,0,3.,false,0.,0,0,0,poly,1,0,[]