In the Results, we reported that the model trained on 4000 samples gave a density prediction error of ϵ ρ M L = 0.62% on the 2-mer test set (Fig. ). To get a better sense of what this error means, we compare this value to other density prediction errors in the literature. We caution that an exact comparison is difficult to make due to differences in methodologies, neural network architec-tures, and types of systems studied. For example, in the study that reported the lowest error of 0.3%, the test systems were simple dimers that did not exceed 25 atoms. By comparison, a structure in our DNA 2-mer test set contains around 126 atoms. Given that reported errors in the literature ranged from 0.3% to 2.5%, the accuracy of our DNA machine learning model is consistent with the most accurate machine learning density studies.