[Boost-users] Lookup on composite key in MultiIndex

Subject: [Boost-users] Lookup on composite key in MultiIndex
From: Chris Jewell (chris.jewell_at_[hidden])
Date: 2010-12-03 08:00:01

Hi All,

A question about fast lookup on ordered indices, if I may.  I have a data structure:

struct Individual
 {
        double I;
        double N;
        ...
}

I need some way of indexing Individuals such that I can perform queries such as "Return the set of Individuals such that Individual::I < T and Individual::N > N".  I'm currently using a MultiIndex that orders the individuals by Individual::I, and therefore gives me fast lookups on the I field.

I had thought about creating a composite key on both I and N, and then using the range() method to return iterators to the required individuals.  However, I can't seem to find the correct syntax for a predicate for the composite key.  Can anyone help me out?  Is there a better way to achieve what I need?

Thanks,

Chris

--
Dr Chris Jewell
Department of Statistics
University of Warwick
Coventry
CV4 7AL
UK
Tel: [phone]