libkdtree++-dev binary package in Ubuntu Bionic i386

 libkdtree++ is a C++ template container implementation of k-dimensional space
 sorting, using a kd-tree. It:
 .
   - supports an unlimited number of dimensions (in theory)
   - can store any data structure, provided the data structure provides
     operator[0 - k-1] to access the individual dimensional
     components (arrays, std::vector already do) and a std::less
     implementation for the type of dimensional components
   - has support for custom allocators
   - implements iterators
   - provides standard find as well as range queries
   - has amortised O(lg n) time (O(n lg n) worst case) on most
     operations (insert/erase/find optimised) and worst-case O(n) space
   - provides a means to rebalance and thus optimise the tree
   - exists in its own namespace
   - uses STL coding style, basing a lot of the code on stl_tree.h
 .
 libkdtree++ only exists as a -dev package as it's only a bunch of C++ header
 files. Therefore, no static or shared library is necessary, allowing for
 ultimate flexibility.

Source package