Task SSB-42: Added a draft for the Holography Data Set (HDS)

.gitattributes

@@ -3,6 +3,7 @@
 CAL/CMakeLists.txt -text
 CAL/CalibrationCommon/CMakeLists.txt -text
 CAL/CalibrationCommon/bin/CMakeLists.txt -text
+CAL/CalibrationCommon/doc/Holography_Data_Set.txt -text
 CAL/CalibrationCommon/lib/CMakeLists.txt -text
 CAL/CalibrationCommon/test/CMakeLists.txt -text
 CAL/CalibrationCommon/test/t_holography_beam_specification_class.py -text

CAL/CalibrationCommon/doc/Holography_Data_Set.txt

+Definition of the Holography Data Set
+
+Authors:  Thomas Jürges <jurges@astron.nl>, Mattia Mancini <mancini@astron.nl>
+Date:  2018-09-07
+Version 1.0
+
+
+The Holography Data Set (HDS)
+
+Attributes in the HDS
+
+- Version:  The HDS is versioned and begins at version 1.0.  Newer versions
+    will have the version the value incremented.  Unit:  n.a.
+- RCU list:  An array that contains the list of RCUs that were used during the
+    holography observation.  Unit:  n.a.
+- mode:  The RCU mode that was used during the holography observation.
+    Unit:  n.a.
+- SAS id:  An array that contains the SAS ids that were created for all
+    observation runs during the hologrpahy observation.  Unit:  n.a.
+- Target station name:  Name of the LOFAR target station.  Unit:  n.a.
+- Target station position:  Position in cartesian coordinates with reference to
+    the Unit:  [m, m, m]
+- Source name:  Name of the source used for the holography observation.
+    Unit:  n.a.
+- Source position:  Celestial coordinates (RA, DEC) of the source.
+    Unit:  [rad, rad]
+- Observation time:  Start and end time stamps of the entire holography
+    observation in MJD.  Unit:  [s]
+- Rotation matrix:  Rotation matrix that allows to convert (RA, DEC)
+    coordinates to (l, m) coordinates and vice versa.  Unit:  n.a.
+- Antenna field positions:  Cartesian coordinates with reference to IRTF of the
+    centre of each antenna field that was used in the holography observation.
+    Unit:  [m, m, m]
+
+
+Data tables in the HDS
+
+- Reference station:  The reference station data table contains the list of
+    all reference stations that were used in the holography observation.
+- nu:  The data table nu contains all frequencies that were used during the
+    holography observation.
+- RA DEC:  The RA DEC table contains the celestial positions of all of the.
+    With the indices frequency and beamlet number the right ascension and
+    declination pointing of the respective beamlet can be determined.
+- data:  The data table is a cube which contains the crosscorrelations for
+    a given frequency nu,
+
+
+Layout of the HDS in HDF5 files
+
+/root
+    /ATTRS
+        /Version (double), hologrpahy file format version
+        /RCU list (vararray[int]), entries are RCU#s used in all observations
+        /mode (int), RCU mode used during all observations
+        /SAS id (vararray[string]), contains all SAS ids of all observations
+        /Target station name (string), name of the target station
+        /Target station position (double[3]), position of the centre of
+            the station in cartesian coordinates
+        /Source name (string), name of the observed source in the sky
+        /Source position (double[2]), RA, DEC of the source in the sky
+        /Observation time (double[2]), Start and end time stamps of the
+            holography observation
+        /Rotation matrix (2-d array, double[3][3]), translation matrix for
+            (RA, DEC) <-> (l, m) conversion
+        /Antenna field positions (1-d array, double[3]), cartesian coordinates
+            of the centres of each antenna field
+    /Reference station (1-d array, string), entries are reference station names
+    /nu (1-d array, double), entries are the frequencies of all observations
+    /RA DEC (2-d array, compound[double, double]), indices are nu index, beamlet#
+    /data (3-d array, vararray[compound[compound[4][double, double], double[3],
+        boolean]], indices are Reference station index, nu index, beamlet#;