### Added - ACSF & Overlap Matrix Feature Maps with derivatives. Spin-or electric field prefactors. - calculation and writing of feature maps and their derivatives to binary and ASCII file (mode 1) - 2G prediction (serial & MPI) - 2G energy and force training (serial & MPI) - most fitting and prediction options - batchwise processing and iteration over chunks of structures - 3G prediction: charges, long-range electrostatic contributions, short-range contributions, and all combined (serial & MPI) - 3G training of charges - 3G training of energies and forces after removing long-range electrostatic contributions - 4G prediction: charges, long-range electrostatic contributions, short-range contributions with force trick, and all combined (serial & MPI) - prediction of Hirshfeld volumina - training of Hirshfeld volumina - OpenMP parallelization for feature maps and intrinsic parallelization of matrix multiplications in forward/backward pass and Kalman filter optimization ### Known Issues - faulty weight initialization in comparison to RuNNer 1. In consequence poor training behavior for large-scale datasets when using a high P initial value (use p_initial < 0.01). - sys_mem test in the CI pipeline fails randomly when other programs are running - in separate pipelines (just restart the pipeline until it works). ### Work in Progress - 4G charge training - 4G energy and force training - committee prediction