Changes between Initial Version and Version 1 of DatabaseBasedAnalysis/calcsource

Timestamp:

08/07/18 17:14:31 (7 years ago)

Author:

tbretz

Comment:

--

DatabaseBasedAnalysis/calcsource

@@ +1 @@
+To calculate the source position for each event (from the '''Events''' table) in the camera, a tool called `calcsource` was developed.
+
+The toll is called like this
+{{{
+calcsource YYMMDDNNN
+}}}
+where '''YYMMDDNNN''' is the identifier of a run created from the night of sun-set '''YYMMDD''' and the run-id '''NNN'''. It is also known as FileId.
+
+== Getting the source ==
+
+The tool then requests right ascension and declination of the source observed with a given run by the following query:
+
+{{{#!sql
+SELECT 
+    Source.fRightAscension, 
+    Source.fDeclination, 
+    Source.fSourceName
+FROM 
+    RunInfo
+LEFT JOIN 
+    Source USING (fSourceKey)
+WHERE 
+    fNight=20YYMMDD
+AND 
+    fRunID=NNN
+}}}
+
+Here, YYMMDD and NNN are again the parts from the FileId given as positional option.
+
+The table names `Source` and `RunInfo` can be altered by the options `--table.source` and `--table.runinfo`.
+
+== Getting events ==
+
+Then, a list of all event times and the pointing position in terms of right ascension/declination together with the corresponding event number is obtained for the given run by
+{{{#!sql
+SELECT 
+    `Ra`, 
+    `Dec`, 
+    MJD, 
+    MilliSec, 
+    NanoSec, 
+    EvtNumber
+FROM 
+    Events
+WHERE 
+    FileId=YYMMDDNNN
+}}}
+
+The FileId comes again from the command line argument. The table name for the '''Events''' table can be altered by `--table.events`.
+
+For source and pointing position, zenith distance and azimuth is calculated using `libnova` and the wrapper `Nova::GetHrzFromEqu`. The result is then rotated into the camera and projected on a plane which gives the x/y coordinates in the camera.
+
+The result is then inserted into a table '''Position''' which name can be altered with `--table.position`. By default, all entries corresponding to the given FileId are deleted from the table before the new positions are inserted running
+{{{#!sql
+DELETE FROM Position WHERE FileId=YYMMDDNNN
+}}}
+
+
+== Table Creation ==
+
+It is not very handy if the SQL table has to be created manually beforehand. Therefore, `calcsource` can automatically create the table. To do this, specify `--create`. The query which would be used to create the table can be printed with `--print-create` even when `--create` has not been specified. Tables are created only if the do not yet exist (`CREATE TABLE IF NOT EXISTS`). To ensure recreation of a table, the old table can be dropped with `--drop`. As any insert operation would fail if the required table is dropped and no new one is created, `--drop` always implies `--create`.
+
+The table is created as
+
+{{{!#sql
+CREATE TABLE IF NOT EXISTS Position
+(
+    FileId INT UNSIGNED NOT NULL,
+    EvtNumber INT UNSIGNED NOT NULL,
+    X FLOAT NOT NULL,
+    Y FLOAT NOT NULL,
+    PRIMARY KEY (FileId, EvtNumber)
+)
+DEFAULT CHARSET=latin1 COLLATE=latin1_general_ci
+}}}
+
+=== Database Engine ===
+
+The default database engine is to create the table with the default of the database. If a database engine (`ENGINE=`) should be forced for the table the `--engine ENGINE` option can be used. Similarly, the row-format (`ROW_FORMAT=`) can be defined using `--row-format FORMAT`. For example:
+
+{{{
+--engine InnoDB --row-format=COMPRESSED
+}}}
+
+== Ignore duplicate entries ==
+
+Usually, the `INSERT` query would fail if another row with the same primary key exists already.  This can be avoided adding the `IGNORE` keyword to the `INSERT` query by `--ignore-errors`, which essentially ignores all errors and turns them into warnings which are printed after the query succeeded.
+
+If the `--update` option is given, column are updated with `ON DUPLICATE KEY UPDATE X=VALUES(X), Y=VALUES(Y)`.
+
+== Source position ==
+
+Instead of obtaining the source position automatically, right-ascension and declination can be specified manually with `--ra` and `--dec`.
+
+== Focal Distance ==
+
+For a correct calculation of X and Y, the focal distance has to be known. The default is 4889mm. It can be altered with `--focal-dist`.
+
+== Debugging ==
+
+The `INSERT` query can be skipped with `--insert`. A dry run which guarantees that nothing in the database is altered can be done with `--dry-run` (note that this might produce subsequent errors).
+
+To print out the meta queries (DROP, CREATE, DELETE, SELECT), the option `--print-meta` exists. The longer `INSERT` query can be printed using `--print-insert`.