Difference between revisions of "Dynamic Spectrum and Imaging"

From EOVSA Wiki
Jump to: navigation, search
(Get Dynamic Sepctrum with SunCASA)
(Get Dynamic Sepctrum with SunCASA)
Line 2: Line 2:
 
==Get Dynamic Sepctrum with SunCASA==
 
==Get Dynamic Sepctrum with SunCASA==
 
Within ''SunCASA'', you are using IPython to interact with the system. This does not mean extensive python experience is necessary. Basic Python interactions are straightforward, e.g., assigning parameters, importing modules, running functions. The first module we introduce is ''dspec''. This module allows you to generate a dynamic spectrum from an MS file, and visualize it. You can select a subset of data by specifying a [https://casa.nrao.edu/Release3.3.0/docs/UserMan/UserMansu112.html time range], [https://casaguides.nrao.edu/index.php/Selecting_Spectral_Windows_and_Channels spectral windows/channels],  [https://casaguides.nrao.edu/index.php/Antenna/Baseline_Selection_Syntax_with_or_without_Autocorrelations antenna baseline]. The selection syntax follows the ''CASA'' convention. More information may be found in the [https://casa.nrao.edu/Release3.3.0/docs/UserMan/UserMansu112.html time range], [https://casaguides.nrao.edu/index.php/Selecting_Spectral_Windows_and_Channels spectral windows/channels],  [https://casaguides.nrao.edu/index.php/Antenna/Baseline_Selection_Syntax_with_or_without_Autocorrelations antenna baseline] pages.
 
Within ''SunCASA'', you are using IPython to interact with the system. This does not mean extensive python experience is necessary. Basic Python interactions are straightforward, e.g., assigning parameters, importing modules, running functions. The first module we introduce is ''dspec''. This module allows you to generate a dynamic spectrum from an MS file, and visualize it. You can select a subset of data by specifying a [https://casa.nrao.edu/Release3.3.0/docs/UserMan/UserMansu112.html time range], [https://casaguides.nrao.edu/index.php/Selecting_Spectral_Windows_and_Channels spectral windows/channels],  [https://casaguides.nrao.edu/index.php/Antenna/Baseline_Selection_Syntax_with_or_without_Autocorrelations antenna baseline]. The selection syntax follows the ''CASA'' convention. More information may be found in the [https://casa.nrao.edu/Release3.3.0/docs/UserMan/UserMansu112.html time range], [https://casaguides.nrao.edu/index.php/Selecting_Spectral_Windows_and_Channels spectral windows/channels],  [https://casaguides.nrao.edu/index.php/Antenna/Baseline_Selection_Syntax_with_or_without_Autocorrelations antenna baseline] pages.
[[file:fig-dspec.png|thumb|center|500px|Fig. 1.]]
+
 
 
<pre>
 
<pre>
 
from suncasa.utils import dspec as ds
 
from suncasa.utils import dspec as ds
Line 14: Line 14:
 
ds.get_dspec(vis=msfile, specfile=specfile, bl=bl, spw=spw, domedian=domedian)
 
ds.get_dspec(vis=msfile, specfile=specfile, bl=bl, spw=spw, domedian=domedian)
 
ds.plt_dspec(specfile, pol='XXYY')
 
ds.plt_dspec(specfile, pol='XXYY')
 
 
</pre>
 
</pre>
 +
[[file:fig-dspec.png|thumb|center|500px|Fig. 1.]]
  
 
==Imaging with SunCASA ==
 
==Imaging with SunCASA ==

Revision as of 13:33, 15 May 2019

Get Dynamic Sepctrum with SunCASA

Within SunCASA, you are using IPython to interact with the system. This does not mean extensive python experience is necessary. Basic Python interactions are straightforward, e.g., assigning parameters, importing modules, running functions. The first module we introduce is dspec. This module allows you to generate a dynamic spectrum from an MS file, and visualize it. You can select a subset of data by specifying a time range, spectral windows/channels, antenna baseline. The selection syntax follows the CASA convention. More information may be found in the time range, spectral windows/channels, antenna baseline pages.

from suncasa.utils import dspec as ds

msfile = 'IDB20170821201020-203020.12s.slfcaled.ms'  # the visbility data
specfile = msfile + '.dspec.npz'  ## The output filename of the dynamic spectrum 
bl = ''    ##  antenna selection
spw = ''    ## Spectral Windows and Channels selection
timeran = ''    ## time range selection
domedian =True    ## select baselines with a median length (0.2~0.8km)
ds.get_dspec(vis=msfile, specfile=specfile, bl=bl, spw=spw, domedian=domedian)
ds.plt_dspec(specfile, pol='XXYY')
Fig. 1.

Imaging with SunCASA

cd to your working directory where the measurement sets file is located.

from suncasa.utils import qlookplot as ql
msfile = 'IDB20170821201020-203020.12s.slfcaled.ms'
vis = msfile
timerange = '20:21:10~20:21:30'  ## time range selection
spw = '3.4~6.0GHz'  ## Spectral Windows and Channels selection
stokes = 'XXYY'     ## polarizations selection
ql.qlookplot(vis, timerange=timerange, spw=spw, stokes=stokes)