@@ -14,7 +14,7 @@ where the **verbose** parameter allows you to have more detailed information abo
+ Python-casacore (formerly "pyrap") is a python interface to the casacore library, which allows the raw data tables (Measurement Sets) to be manipulated and the data plotted via python scripts. These allow you to customize what is plotted, and can be significantly faster than CASA for plotting large datasets. An extensive description of the python-casacore utilities is available `online <http://casacore.github.io/python-casacore/>`_.
+ Visibilities can be plotted relatively rapidly by making use of the combination of python-casacore and the plotting package PGPLOT, both of which work quickly. The script **uvplot.py** [#f2]_ can be used to plot visibility data and can be significantly faster than the PLOTMS task in CASA.
+ `CASA <http://casa.nrao.edu/>`_ is the python-based next generation replacement for AIPS/AIPS++ and can be used to display the data. Be aware that trying to inspect the raw visibilities with CASA will produce a "**segmentation fault**" error. To avoid this, you should make a copy of the dataset with DPPP (see the first example parset in Sect.~\ref{theparsetfile}). Moreover, when opening with CASA a MeasurementSet observed between May and October 2011, you will get an **Unrecognized mount type** error [#f3]_. CASA has multiple functionalities that allows one to inspect different data products.
+ `CASA <http://casa.nrao.edu/>`_ is the python-based next generation replacement for AIPS/AIPS++ and can be used to display the data. Be aware that trying to inspect the raw visibilities with CASA will produce a "**segmentation fault**" error. To avoid this, you should make a copy of the dataset with DPPP (see the first example parset in Sect.~\ref{theparsetfile}). **Also note** that the Radio Observatory now stores the LOFAR data as Dysco compressed measurement sets and hence CASA cannot be used to inspect them. You must decompress the measurement set first if you want to use CASA for data inspection [#f6]_. Moreover, when opening with CASA a MeasurementSet observed between May and October 2011, you will get an **Unrecognized mount type** error [#f3]_. CASA has multiple functionalities that allows one to inspect different data products.
* **casabrowser** can be used to inspect the content of a Measurement Set.
* **casaplotms** can be used to visibility data against different parameters.
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@@ -233,6 +233,7 @@ The following command lets you make a movie of the line plots like the one shown
.. [#f1] This chapter is maintained by `A. Shulevski <mailto:shulevski@astron.nl>`_ and `Valentina Vacca <mailto:vvacca@oa-cagliari.inaf.it>`_.
.. [#f2] The script was written by George Heald and is available through the `LOFAR GitHub repository <https://github.com/lofar-astron/LOFAR-Contributions>`_.
.. [#f6] For more information, consult `this webpage <https://old.astron.nl/radio-observatory/lofar-data-processing/dysco-compression/compressing-lofar-measurement-sets-using-d>`_.
.. [#f3] This is due to the fact that the MS writer version used during those months was specifying the antenna mount as FIXED, and not as ALT-AZ, which is CASA friendly. To solve this problem, you can run the following **taql** command on your MS as *taql 'update <ms name>/ANTENNA set MOUNT="X-Y" '*
.. [#f4] The **SPLIT** task will be deprecated in favor of the **MSTRANSFORM** task beginning with CASA v.4.1.0.
.. [#f5] The script is available through the `LOFAR GitHub repository <https://github.com/lofar-astron/LOFAR-Contributions>`_.
