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Eugene Kirpichov commented on MATH-169: --------------------------------------- Rolling percentiles seems like an interesting and useful thing to do; however, the implementation looks to me like it might have poor performance under some circumstances. Namely, the SortedDeque class uses a LinkedList for storing items in order, and does a Collections.binarySearch on it. However, Collections.binarySearch is very inefficient for the LinkedList: actually, so inefficient that a linear search is much faster. If you are maintaining a fixed-size sorted queue, I'd suggest you to use a binary heap; when it is full and a new item goes in, insert the new item and delete the minimum from the heap. One might simply use a PriorityQueue, or implement a heap of double's for greater efficiency. > Rolling statistics > ------------------ > > Key: MATH-169 > URL: https://issues.apache.org/jira/browse/MATH-169 > Project: Commons Math > Issue Type: Improvement > Reporter: Bradford N. Cross > Assignee: Phil Steitz > Fix For: 2.1 > > Attachments: FirstRollingPatch, RankRollingPatch > > > Rolling statistics with optimized calculation algorithms. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.