Merger and Appender
**********************************************************

..  figure:: /Images/Merger_Appender/Overview.png
   :scale: 75 %
   :align: center

   Difference Merger & Appender
  
Merger
==========================================================

The general function of the *Merger* is to join two measurements which
were recorded at the same time with different logger systems.

It does not matter whether the measurements have the same or different
channels. Length does not matter either, as the channel values of the
shorter measurement are kept constant outside the overlapping area.

A difference in function exists and depends on where the merge is
started from:

Positional merge
----------------------------------------------------------

If two measurements are loaded in the *Analyzer* and the merge is
started from there (*Analyzer Functions Merge 2 measurements*), the
boxes where the measurements and the channels can be selected are
disabled in the Merger settings window.

These fields are disabled because during the position-based merge the
measurements are merged as they are currently positioned in relation to
each other in the *Analyzer*! The offset of the measurements to each
other set via the current positions is adopted during the merge.

In the lower part of the window, it can be selected how to proceed if
same channel names are existing.

Channel-related merge
----------------------------------------------------------

If the Merger.exe is started directly from the application directory
(*WinARace [CTRL]+[ALT]+[A*]), the boxes for measurement and channel
selection are enabled.

These fields are activated because it can now be decided directly which
channel is to be used to merge the two measurements! With
channel-related merging, the measurements are matched so that the
selected merging channels are exactly overlap each other. 

.. important:: 
   It is recommended to use GNSS/GPS time channels (#SOD).


In the lower part of the window, it can be selected how to proceed if
same channel names are existing.

Appender
==========================================================
The general function of the *Appender* is to join two measurements that
were recorded one after the other.

It does not matter if the measurements have a different length and if
they were recorded with different logger systems, but all measurements
must contain exactly the same channels (same sampling rate, same data
type, ...)!



.. important:: 
   The Appender.exe can only be started directly from the application
   directory (*WinARace [CTRL]+[ALT]+[A]),* where the measurements to be
   appended can be selected.