Figure 6.

The speed of the EM algorithm and the requirements on the data set. (a) The time required for a single iteration is linearly dependent on the number of diffraction patterns. (b) For the case of PSI experimental data, a minimum set of 5000 diffraction patterns is required to guarantee reliable converged models. The CIM percentage shown on the vertical axis means the percentage of recovered indexing modes that are consistent with the reference model. When the sample size is smaller than 500, the EM algorithm fails to resolve the indexing ambiguity. For the cases where 1000 to 3000 patterns form the test set, detwinning can be successful but the large error bars suggest that the success rate is not guaranteed, so more runs would be desired.