:tocdepth: 3

base/frameworks/sumstats/plugins/topk.zeek
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.. zeek:namespace:: SumStats

Keep the top-k (i.e., most frequently occurring) observations.

This plugin uses a probabilistic algorithm to count the top-k elements.
The algorithm (called Space-Saving) is described in the paper Efficient
Computation of Frequent and Top-k Elements in Data Streams", by
Metwally et al. (2005).

:Namespace: SumStats
:Imports: :doc:`base/frameworks/sumstats </scripts/base/frameworks/sumstats/index>`

Summary
~~~~~~~
Redefinitions
#############
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:zeek:type:`SumStats::Calculation`: :zeek:type:`enum` 
                                                      
                                                      * :zeek:enum:`SumStats::TOPK`:
                                                        Keep a top-k list of values.
:zeek:type:`SumStats::Reducer`: :zeek:type:`record`   
                                                      
                                                      :New Fields: :zeek:type:`SumStats::Reducer`
                                                      
                                                        topk_size: :zeek:type:`count` :zeek:attr:`&default` = ``500`` :zeek:attr:`&optional`
                                                          Number of elements to keep in the top-k list.
:zeek:type:`SumStats::ResultVal`: :zeek:type:`record` 
                                                      
                                                      :New Fields: :zeek:type:`SumStats::ResultVal`
                                                      
                                                        topk: :zeek:type:`opaque` of topk :zeek:attr:`&optional`
                                                          A handle which can be passed to some built-in functions to get
                                                          the top-k results.
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Detailed Interface
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