Re: [Boost-users] [ICL] interval_map question

Hi Antal, the output of your program is correct. This is because interval_maps do *not* store interval value pairs (I,v), if v==0 or more precisely, if v is the identity element of the codomain_type of associated values. 2011/5/25 Antal A. Buss :

Hi all,

I'm trying to use interval_map to implement some kind of range to value directory, but I have some non expected results.

The test code I'm using is: ------------------------ #include <iostream> #include #include

using namespace std; using namespace boost::icl;

int main(int argc, char const **argv) {  interval_map imap;

// use interval_map imap; // if you want to store zeroes as associated values.

 typedef discrete_interval interval_t;

 imap += make_pair(construct(0, 7, interval_bounds::closed()),0);  cout << "imap: " << imap << endl;

 imap.set(make_pair(construct(0, 0, interval_bounds::closed()),1));  cout << "imap: " << imap << endl;

 imap.erase(construct(3, 3, interval_bounds::closed()));  cout << "imap: " << imap << endl; } ------------------------

The result I got is:  imap: {}  imap: {([0,0]->1)}  imap: {([0,0]->1)}

Correct result, because [0,7]->0 is not stored. There is a MapTraits parameter http://www.joachim-faulhaber.de/boost_icl/doc/libs/icl/doc/html/boost_icl/co... Default for MapTraits is the value 'partial_absorber'. The _absorber part of the name indicates, that interval-value-pairs associated to 0 are absorbed. So a segment of the interval_map "quantified" zero disappears, keeping the map minimal. If you need to store zeros, choose partial_enricher as MapTrait. It is called _enricher, because (I,0)-segments, that may occur through aggregating operations accumulate over time. So using this type of interval map: interval_map imap;

but the result I was expecting is:  imap: {([0,7]->0)}  imap: {([0,0]->1)((0,7]->0)}  imap: {([0,0]->1)((0,3)->0)((3,7]->0)}

you will get the desired result. Best regards, Joachim -- Interval Container Library [Boost.Icl] http://www.joachim-faulhaber.de