DateSense is for detecting the format of date strings. It can be used to return a convenient format string that you can pass to strptime or strftime. It accepts any number of dates as input, which it will assume all share the same format. And if the default parser settings aren't working for your data it's easy to customize the rules which tell the parser what to expect.

To parse one or more date strings using default settings, you need only two lines. Here's an example that outputs the string "%d %b %Y":

>>> import DateSense
>>> print DateSense.detect_format( ["15 Dec 2014", "9 Jan 2015"] )
%d %b %Y

Various rule objects tell the parser what assumptions to make regarding how dates are formatted. Here's an example - this rule tells the parser how to recognize parts of date strings that look like they fit the pattern HH:MM:SS.

rule_pattern_hms = DateSense.DSPatternRule( (('%H','%I'),':','%M',':','%S'), posscore = 3 )

Custom rules can be useful if, for example, you have a nonstandard format you need to anticipate that the parser wasn't able to recognize using the default rules. You could add the format as a pattern rule to let the parser know what to expect when it encounters directives in that sequence.

There are a few other kinds of rules, thoroughly documented in DSrule.py. The default rules are all defined as attributes of the DSoptions class so that you can pick and choose as you see fit if you don't want to write your own. If you were to create a collection of rules you wanted the parser to use instead of the default, you could use this syntax:

DateSense.detect_format( dates, rules )

Enjoy!