libcruft-util/test/kmeans.cpp

#include <cruft/util/tap.hpp>

#include <cruft/util/kmeans.hpp>

#include <cruft/util/point.hpp>


///////////////////////////////////////////////////////////////////////////////
int
main ()
{
    cruft::TAP::logger tap;

    // create one point and check it 'converges' to this one point
    {
        const std::array<cruft::point3f,1> p { {{1,2,3}} };
        std::array<cruft::point3f,1> q;

        cruft::kmeans (cruft::view{p}, cruft::view{q});
        // clang#19-rc2: ICE when instantiating p == q
        //
        // clang++-19: clang/include/clang/AST/DeclTemplate.h:1938:
        //  void clang::ClassTemplateSpecializationDecl::setPointOfInstantiation(clang::SourceLocation):
        //  Assertion `Loc.isValid() && "point of instantiation must be valid!"' failed.
        //
        // So just compare the items directly.
        static_assert (p.size () == q.size ());
        tap.expect_eq (p[0], q[0], "single point, single k");
    }

    // create two vectors, check if the mean converges to their average
    {
        const std::array<cruft::vector3f,2> p {{
            {1}, {2}
        }};
        std::array<cruft::vector3f,1> q;

        cruft::kmeans (cruft::view{p}, cruft::view{q});
        tap.expect_eq (q[0], (p[0]+p[1])/2, "two point, single k");
    }

    return tap.status ();
}