# period_calc.cpp

Calculates if a date is in an 'irregular' collection of periods using period calculation functions.

    /*
    This example demonstrates a simple use of periods for the calculation
    of date information.

    The example calculates if a given date is a weekend or holiday
    given an exclusion set.  That is, each weekend or holiday is
    entered into the set as a time interval.  Then if a given date
    is contained within any of the intervals it is considered to
    be within the exclusion set and hence is a offtime.

    Output:
    Number Excluded Periods: 5
    20020202/20020203
    20020209/20020210
    20020212/20020212
    20020216/20020217
    In Exclusion Period: 20020216 --> 20020216/20020217
    20020223/20020224

    */

    #include "boost/date_time/gregorian/gregorian.hpp"
    #include <set>
    #include <algorithm>
    #include <iostream>

    typedef std::set<boost::gregorian::date_period> date_period_set;

    //Simple population of the exclusion set
    date_period_set
    generateExclusion()
    {
      using namespace boost::gregorian;
      date_period periods_array[] =
        { date_period(date(2002,Feb,2), date(2002,Feb,4)),//weekend of 2nd-3rd
          date_period(date(2002,Feb,9), date(2002,Feb,11)),
          date_period(date(2002,Feb,16), date(2002,Feb,18)),
          date_period(date(2002,Feb,23), date(2002,Feb,25)),
          date_period(date(2002,Feb,12), date(2002,Feb,13))//a random holiday 2-12
        };
      const int num_periods = sizeof(periods_array)/sizeof(date_period);

      date_period_set ps;
      //insert the periods in the set
      std::insert_iterator<date_period_set> itr(ps, ps.begin());
      std::copy(periods_array, periods_array+num_periods, itr );
      return ps;

    }

    int main()
    {
      using namespace boost::gregorian;

      date_period_set ps = generateExclusion();
      std::cout << "Number Excluded Periods: "  << ps.size() << std::endl;

      date d(2002,Feb,16);
      date_period_set::const_iterator i = ps.begin();
      //print the periods, check for containment
      for (;i != ps.end(); i++) {
        std::cout << to_iso_string(*i) << std::endl;
        //if date is in exclusion period then print it
        if (i->contains(d)) {
          std::cout << "In Exclusion Period: "
              << to_iso_string(d) << " --> " << to_iso_string(*i)
              << std::endl;
        }
      }

      return 0;

    }