title: c++ pivot table implementation
body: <p>Similar to this question <a href="https://stackoverflow.com/questions/1069677/pivot-table-in-c-sharp">Pivot Table in c#</a>, I'm looking to find an implementation of a pivot table in c++. Due to the project requirements speed is fairly critical and the rest of the performance critical part project is written in c++ so an implementation in c++ or callable from c++ would be highly desirable. Does anyone know of implementations of a pivot table similar to the one found in Excel or open office?</p>
  
  <p>I'd rather not have to code such a thing from scratch, but if I was to do this how should I go about it? What algorithms and data structures would be good to be aware of? Any links to an algorithm would be greatly appreciated.</p>