Archaeological dataset records often give a textual expression of dating rather than absolute numeric years for the dating of artefacts. These textual data values can be in a variety of formats, sometimes expressed in different languages. There can be prefixes present such as 'Circa', 'Early', 'Mid', 'Late' - and suffixes such as 'A.D.', 'B.C.', B.P.' that may influence the dates intended. This can present a data integration issue, as illustrated in the table below:

Normalising this data can make later search and comparison of the records easier. We can do this by supplementing the original values with additional attributes defining the start and end dates of the timespan. This application attempts to match a set of textual values representing timespans to a number of known patterns, and from there to derive the intended start/end dates of the timespan. For some cases the start/end dates are present and can be extracted directly from the textual string, however in most cases a degree of additional processing is required after the initial pattern match is made. The output facilitates the fairer comparison of textual date spans as often expressed in datasets. Due to the wide variety of formats possible (including punctuation and spurious extra text), the matching patterns developed cannot comprehensively cater for every possible free-text variation present, so any remaining records not processed by this initial automated method (start/end years are blank) can be manually reviewed and assigned suitable start/end dates.

The output dates produced are relative to Common Era (CE). Centuries are set to start at year 1 and end at year 100. Prefix modifiers for centuries take the following meaning in this application:

In the case of decades, centuries or stated tolerances, an offset is added or subtracted from the initial extracted year in order to interpret the overall extents of the year span being expressed. (e.g. "1540±9" = min year 1531, max year 1549)

For matches on known named periods (e.g. Georgian, Victorian etc.) the start/end years are derived from suitable authority list lookups.

Command: timespans -i:{inputFileName} [-o:{outputFileName}] [-l:{languageCode}]

The name (including path) of a text file containing a list of the timespan expressions to be matched, one per line. The matching patterns used are case insensitive. If no match is found then a result is still returned, having blank dates - indicating no appropriate match.

The name (including path) of a text file to write the output to. If this file is not present it will be created, otherwise it will be overwritten. If this parameter is not present then the file name used will be the input file name appended with ".out.txt" The output data format is tab delimited UTF-8 text, this can be easily used within spreadsheet applications for further processing as required.

The ISO639-1:2002 language code corresponding to the language of the input data. This hints to the underlying matching process the most appropriate matching patterns to use. The languages with best support so far are English ('en') and Italian ('it') - some matching patterns are present for Welsh ('cy'), German ('de'), French ('fr'), Spanish ('es') and Swedish ('sv') but these are currently comparatively underdeveloped and untested with representative data. If the language parameter is omitted or is not one of the recognised values then it will default to 'en' (English).

Command: timespans -i:{inputFileNameWithPath} [-o:{outputFileNameWithPath}] [-l:{languageCode}]

Command: timespans -i:myinput.txt -o:myoutput.txt -l:en

myinput.txt: The input is a text file containing one timespan value per line e.g.

1839-1895
1839-75
c.1521
Early 2nd Century

myoutput.txt: The output is a tab delimited text file with years (in ISO 8601 format) assigned to the timespan values

Command: timespans -i:myinput.txt -o:myoutput.txt -l:it

myinput.txt:

140-144 d.C.
III e lo II secolo a.C.
intorno a VI sec. d.C.
tra IV e III secolo a.C.
575-400 a.C.

myoutput.txt: