The article discusses computational analysis techniques for classifying local atomic arrangements in large-scale atomistic simulations of crystalline solids. It compares typical analysis algorithms such as Common Neighbor Analysis (CNA), Centrosymmetry Analysis, Bond Angle Analysis, Bond Order Analysis, and Voronoi Analysis. The author proposes an extension to the CNA method, called Adaptive Common Neighbor Analysis (a-CNA), which is suitable for multi-phase systems. Additionally, a new structure identification algorithm, Neighbor Distance Analysis (NDA), is introduced to identify atomic structure units in grain boundaries. The paper provides a performance comparison of these methods and highlights their strengths and weaknesses. The NDA method is particularly useful for identifying complex structural environments in crystal defects. The author also implements all discussed algorithms for benchmarking purposes and provides the source code for reference. The article concludes with a discussion on the limitations and future directions of structure characterization techniques in atomistic simulations.The article discusses computational analysis techniques for classifying local atomic arrangements in large-scale atomistic simulations of crystalline solids. It compares typical analysis algorithms such as Common Neighbor Analysis (CNA), Centrosymmetry Analysis, Bond Angle Analysis, Bond Order Analysis, and Voronoi Analysis. The author proposes an extension to the CNA method, called Adaptive Common Neighbor Analysis (a-CNA), which is suitable for multi-phase systems. Additionally, a new structure identification algorithm, Neighbor Distance Analysis (NDA), is introduced to identify atomic structure units in grain boundaries. The paper provides a performance comparison of these methods and highlights their strengths and weaknesses. The NDA method is particularly useful for identifying complex structural environments in crystal defects. The author also implements all discussed algorithms for benchmarking purposes and provides the source code for reference. The article concludes with a discussion on the limitations and future directions of structure characterization techniques in atomistic simulations.