Tucson format
Tucson format or decadal format or rwl format is one of the most common formats for storing ring width data. It is the standard format for ITRDB. It is a text file format. Different extensions are used, such as .rwl, .crn, .tuc and .dec. (.crn is used for derivate chronologies). The name comes from the city of Tucson in Arizona.
A Tucson file consists of three lines of meta data followed by an undefined number of data lines (and cores). A data line consist of the core identity (max 8 alphanumeric characters, i.e. letters or digits), the year of the oldest measurement of the line (4 digits)[1] ring width data, up to ten rings per line. Measurement data is either given with 3 or 4 digits according to resolution. Except for the first and last lines of each core there are measurements for one decade per line. After the youngest ring there is a "999" as a stop mark. Missing data mark is -999.
PMkr12b 1781 120 87 69 122 108 85 125 114 77 PMkr12b 1790 134 131 114 97 117 49 69 100 123 89 PMkr12b 1800 137 89 -999 79 44 38 62 99 68 26 PMkr12b 1810 27 43 51 57 36 999
An example of a three digit resolution sample which covers the timespan AD 1781-1814, with a missing ring for AD 1802 (-999). The width of AD 1781 (the first year) annual ring is 1.20 mm and for 1782 AD 0.87 mm.
Examples
These examples are taken from comments within the CDendro code. Best would be if we could have two sections with awkward data - one for each precision - that could be used for testing Tucson format reading capability of software.
'Examples of decadal file format: 'The usual ending of a sample is like this: '6682 1980 143 231 154 145 150 201 130 156 245 137 '6682 1990 141 202 120 96 999 'NM002 1632 90 92 91 174 84 45 185 111 'NM002 1640 116 72 91 49 85 146 125 126 136 131 'Here is an example from brit9.rwl. 'SH387C 1170 14 16 14 19 22 22 26 16 23 23 'SH387C 1180 17 11 14 12 999 0 0 0 0 0 'SH387D 1078 48 48 'SH387D 1080 50 42 46 62 49 53 41 28 17 31 ' 'Here is a snappet from brit045.rwl: 'Q 9730 990 72 98 112 124 107 132 137 145 114 80 'Looks very much normal, but ends with two Asciichar(13) characters which 'will not be trimmed away by the VB Trim function. 'The normal start of a sample is like this: '6682 1884 261 267 191 189 215 309 '6682 1890 357 284 248 174 274 271 229 201 200 130 'But here is a snappet from brit5.rwl: 'WRU9 1190 190 192 218 213 204 259 206 150 178 149 'WRU9 1200 198 232 151 199 175 196 9990 9990 9990 9990 'WRU13 1075 9990 9990 9990 9990 9990 342 426 240 213 217 'It both ends and start a sample with 9990 markers. ' 'From ca535.rwl: 'MWK964 1970 16 11 22 25 9 13 26 24 23 16 'MWK964 1980 999 'MWK965 509 62 0 0 0 0 0 0 0 0 0 'MWK965 510 47 45 25 19 33 24 32 51 24 22 'where zeroes are filled into positions which are not in use 'and this with a -0 instead of 0 or -999 'MWK401 -3550 26 21 19 20 28 21 13 11 -0 11 ' 'Format still not handled with example from fran009.rwl: '606 13 1570 24 31 30 25 26 24 27 27 33 30 '606 13 1580 20 999 '606 13 1586 20 19 19 18 '606 13 1590 27 20 20 25 22 22 23 23 10 15 'I.e. a gap of missing rings is handled as two series one after the other though with the same identity.
CDendro interpretation
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See also CDendro naming standard
Limitations of the Tucson format
Notes
- ↑ If 5 digits are needed for the year, i.e. older than -999, the identity cannot be more than 7 alphanumeric characters.