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Gabor Gevay commented on FLINK-2144: ------------------------------------ But why couldn't we provide FoldFunctions for these in the API? > Incremental count, average, and variance for windows > ---------------------------------------------------- > > Key: FLINK-2144 > URL: https://issues.apache.org/jira/browse/FLINK-2144 > Project: Flink > Issue Type: New Feature > Components: Streaming > Reporter: Gabor Gevay > Priority: Minor > Labels: statistics > > By count I mean the number of elements in the window. > These can be implemented very efficiently building on FLINK-2143: > Store: O(1) > Evict: O(1) > emitWindow: O(1) -- This message was sent by Atlassian JIRA (v6.3.4#6332)