Figure shows the percentage of cumulative proportion of variance explained by an increasing amount of principal components. We chose to use 8 components since it is enough to recover more than 90% of the initial variance for the full data set (without distinguishing different fibers). (removing the labels distinguishing among different fibers) and projected the SOAP features for the three systems onto different maps using the first two principal components. We also checked the robustness of our analysis by comparing the results obtained using cutoffs of 8 Å, 12 Å or 16 Å.