0 votes
asked by (350 points)

I'd like to create a vector of QNs in a for loop that are then used to create one Index. The relevant code in my .h defining my class ExcitonSite is

ExcitonSite(Args const& args = Args::global())
{
    int dim = args.getInt("on_site_dim", 5);
    auto ts = TagSet("Site,S="+str(dim));
    auto v = stdx::reserve_vector<Index>(2 * dim + 1);
    for (int j = -dim; j <= dim; ++j)
    {
        auto q = QN({"Sz",j});
        v.emplace_back(q, 1);
    }
    s = Index(std::move(v),Out,ts);
}

This however is throwing an error "error: no matching function for call to..." in the last line. Thoughts?

1 Answer

+1 vote
answered by (350 points)
edited by

For those who are interested, this is the solution:

   ExcitonSite(Args const& args = Args::global())
{
    dim = args.getInt("on_site_dim", 5);
    auto ts = TagSet("Site,Exciton");
    int n = args.getInt("SiteNumber");
    ts.addTags("n="+str(n));
    auto v = std::vector<std::pair<QN, long int>>(2 * dim + 1);
    int cntr = 0; 
    for (int j = -dim; j <= dim; ++j)
    {
        auto q = QN({"Sz",j});
        v.emplace_back(q, 1);
    }
    s = Index(std::move(v),Out,ts);
}
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