Re: [Boost-users] [BGL] Inverse property mapping?

From: Alejandro M. Aragón (aaragon2_at_[hidden])
Date: 2007-10-13 16:29:52

Aaron Windsor wrote:
> On 10/12/07, "Alejandro M. Aragón" <aaragon2_at_[hidden]> wrote:
>> Hello everyone,
>>
>> I've been looking for some time at the documentation and I couldn't find
>> a single way to obtain an inverse mapping for a property map. That is,
>> given a property p, I would like to obtain a vertex descriptor v. It
>> seems that the mapping is only in one direction. Is there a way to
>> obtain the inverse mapping too? If so, what is the complexity associated
>> with obtaining the vertex descriptor?
> 
> Hi Alejandro,
> 
> Unless you explicitly set up an inverse property map, there's no way
> to invert a mapping using the property map interface. The only
> interface to retrieving anything from the property map is by key:
> get(map, key) (or map[key] if you're using an LValuePropertyMap).
> 
> Regards,
> Aaron

Hi Aaron, thanks for replying. The way I solved this problem is just 
using a map from the standard library for the inverse mapping. I 
couldn't think about any better solution. Is this what you referred as 
explicitly setting up an inverse map?

a²