Per #2476, clarify the match_to_track TC-Pairs config option for CIRA…

…_DIAG_RT sources. If left empty, the ATCF ID of the corresponding tracks is read from the CIRA diagnostics input file.

data/config/TCPairsConfig_default

@@ -145,7 +145,7 @@ diag_info_map = [
       diag_source    = "CIRA_DIAG_RT";
       track_source   = "GFS";
       field_source   = "GFS_0p50";
-      match_to_track = [ "GFS" ];
+      match_to_track = [];
       diag_name      = [];
    },
    { 

docs/Users_Guide/tc-pairs.rst

@@ -291,7 +291,7 @@ ____________________
        diag_source    = "CIRA_DIAG_RT";
        track_source   = "GFS";
        field_source   = "GFS_0p50";
-       match_to_track = [ "GFS" ];
+       match_to_track = [];
        diag_name      = [];
     },
     {
@@ -307,7 +307,11 @@ A TCMPR line is written to the output for each track point. If diagnostics data
 
 The **diag_info_map** entries define how the diagnostics read with the **-diag** command line option should be used. Each array element is a dictionary consisting of entries for **diag_source**, **track_source**, **field_source**, **match_to_track**, and **diag_name**.
 
-The **diag_source** entry is one of the supported diagnostics data sources. The **track_source** entry is a string defining the ATCF ID of the track data used to define the locations at which diagnostics are computed. This string is written to the **TRACK_SOURCE** column of the TCDIAG output line. The **field_source** entry is a string describing the gridded model data from which the diagnostics are computed. This string is written to the **FIELD_SOURCE** column of the TCDIAG output line type. The **match_to_track** entry specifies a comma-separated list of strings defining the ATCF ID(s) of the tracks to which these diagnostic values should be matched. The **diag_name** entry specifies a comma-separated list of strings for the tropical cyclone diagnostics of interest. If a non-zero list of diagnostic names is specified, only those diagnostics appearing in the list are written to the TCDIAG output line type. If defined as an empty list (default), all diagnostics found in the input are written to the TCDIAG output lines.
+  - The **diag_source** entry is one of the supported diagnostics data sources.
+  - The **track_source** entry is a string defining the ATCF ID of the track data used to define the locations at which diagnostics are computed. This string is written to the **TRACK_SOURCE** column of the TCDIAG output line.
+  - The **field_source** entry is a string describing the gridded model data from which the diagnostics are computed. This string is written to the **FIELD_SOURCE** column of the TCDIAG output line type.
+  - The **match_to_track** entry specifies a comma-separated list of strings defining the ATCF ID(s) of the tracks to which these diagnostic values should be matched. For the SHIPS_DIAG_RT source, this is required since it is the only way to associate diagnostics with track ATCF IDs. For the CIRA_DIAG_RT source, this is optional. If a non-zero list is provided, the diagnostics will be matched to tracks for the specified ATCF ID(s). If defined as an empty list (default), the ATCF ID will be extracted from each CIRA diagnostic file and used to match the diagnostics to track data.
+  - The **diag_name** entry specifies a comma-separated list of strings for the tropical cyclone diagnostics of interest. If a non-zero list of diagnostic names is specified, only those diagnostics appearing in the list are written to the TCDIAG output line type. If defined as an empty list (default), all diagnostics found in the input are written to the TCDIAG output lines.
 
 ____________________
 

internal/test_unit/config/TCPairsConfig_DIAGNOSTICS

@@ -136,7 +136,7 @@ diag_info_map = [
       diag_source    = "CIRA_DIAG_RT";
       track_source   = "GFS";
       field_source   = "GFS_0p50";
-      match_to_track = [ "GFS" ];
+      match_to_track = [];
       diag_name      = [ ${CIRA_RT_DIAG_NAME} ];
    },
    {