Robust powder auto-indexing using many peaks

A new powder auto‐indexing method for the CONOGRAPH software [Oishi‐Tomiyasu (2013). Acta Cryst. A69, 603–610] can carry out exhaustive powder auto‐indexing in a short time, even if the q values of many peaks are used, with sufficient consideration given to their observational errors. This article explains that the use of many q values is essential to make powder auto‐indexing robust against dominant zones and missing or false peaks in the input. Results from CONOGRAPH for 25 real diffraction patterns, including difficult cases, are presented. Owing to a sorting criterion for zones defined in the previous article, the computation times were reduced by a factor of between 18 and 250, and exhaustive powder auto‐indexing was completed in 5 min at most.