Package org.tridas.io.formats.tucson

The Tucson tree ring laboratory's file format.

See:
Description

Class Summary

TridasToTucsonDefaults	Place to hold and change default fields for the Tucson filetype
TucsonFile
TucsonReader	Reader for the Tucson file format.
TucsonToTridasDefaults	here for the library user to create and pass in the loadFile() arguments
TucsonWriter	Writer for the Tucson file format.

Enum Summary

TridasToTucsonDefaults.TucsonField
TucsonToTridasDefaults.TucsonDefaultField

Package org.tridas.io.formats.tucson Description

The Tucson tree ring laboratory's file format. This has been the canonical file format since the punchcard days. Unfortunately, since it's just the punchcard format in a text file, it has numerous shortcomings:

• minimal metadata support just three 80 character lines in a rigid format that many ignore
• relative/absolute flag starts in column 80 of the title, making it inconvenient to edit with most text editors
• officially uses astronomical dates rather than BC/AD so 0 = 1BC etc however most people enter data as if it does use BC/AD. This can cause confusion and data errors.
• only has space for 4 characters to represent years so officially only allows data from 1000BC (-999) to 9999AD (9999). People tend either to add 8000 to all years or pinch the last character from the keycode to allow them to represent years with 5 characters. Neither method is official or documented though.
• no way to store auxiliary numerical data like Weiserjahre
• no way to indicate the variable that has been measured so often people use filenames to indicate early/late wood files
• no way to distinguish with certainty if a summed file is indexed
• no MIME type (even an application/x- one), standard file extension, or telltale opening signature
• variety of no data and stop characters used by different programs
• different number of characters used for keycode in different programs (6 or 8)

What it does do is store dendro data, readable by most dendro programs.

File Format

There are two variants of Tucson files: raw and chronologies. Raw files (RWL) contain just ring width values, whereas chronologies also contain 'sample depth/count' values alongwide each ring width.

Due to there being a minimal specification for the format, implementations over the years have introduced many subtle variations which need to be handled. For instance, the number of keycode characters, the number of characters for the year marker, whether there should be any placeholder values after the 'end of data' marker, the units of measurement etc etc. This class should handle all popular variants of the Tucon format correctly.

See NOAA's Tree Ring Data Description. The CDendro wiki also contains useful information.