I tried with small arrays, it worked but it raised error with the larger ones.
Running ICP (point-to-plane, no outliers)
openGLScratch: /mnt/linuxdisk/localdev/boost_1_76_0/build/include/boost/multi_array/base.hpp:177: Reference boost::detail::multi_array::value_accessor_one<T>::access(boost::type<Reference>, boost::detail::multi_array::value_accessor_one<T>::index, TPtr, const size_type*, const index*, const index*) const [with Reference = const float&; TPtr = const float*; T = float; boost::detail::multi_array::value_accessor_one<T>::index = long int; boost::detail::multi_array::multi_array_base::size_type = long unsigned int]: Assertion `idx - index_bases[0] >= 0' failed.
Aborted (core dumped)
sum += the_data[ind[k]][c];