help regarding syntax

Hi, any idea on what is this code doing:
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//=================================
1 #include <boost/scoped_ptr.hpp>
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...
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3 typedef std::vector<std::vector<pair<size_t, size_t ParamsType;
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5 /*
6 *Is the following a boost shared pointer to a "ParamsType" object?
7 */
8 shared_ptr<ParamsType>& params;
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...
14 params.reset(new ParamsType(m_pred_map->size()));
15 for (size_t pid = 0; pid < m_pred_map->size(); ++pid) {
16 vector<pair<size_t, size_t& param = (*params)[pid]; // ??
...
}
//=================================
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I have problems with lines 14 & 16. First of all, is ParamsType a vector
of vectors of pairs? Then I think params is a pointer to that. Then, we
probably instantiate a new ParamsType and let params point at it. Right?
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But then, what's happening in line 16?
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Thanks in advance
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Giuseppe

Anybody? please.. :) Is
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vector<pair<size_t, size_t& param = (*params)[pid];
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a kind of cast?
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cheers
Giuseppe
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Giuseppe:G: wrote:>>>>>>>

If you think of it as a 2D matrix of "pair" objects, then this loop is
getting each "row" of of the matrix. The term "param" in most cases
would be used as a reference, because it is easier to read/type than
repeating "(*params)[pid]" everywhere else in the loop. It is just an
alias.
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hth,
Joe Cook
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