Class: ApacheCrunch::Distribution

Inherits:
ProcedureRoutine show all
Defined in:
lib/procedure_dsl.rb

Overview

DSL routine that finds the distribution of (numeric) values to which the given block evaluates

For example,

distribution 100 do
    bytes_sent
end

would return a hash with keys from 0 up by multiples of 100, the value of each being the number of entries for which bytes_sent is between that key and the next key.

Instance Method Summary collapse

Methods inherited from ProcedureRoutine

#finish, #initialize, #method_missing

Constructor Details

This class inherits a constructor from ApacheCrunch::ProcedureRoutine

Dynamic Method Handling

This class handles dynamic methods through the method_missing method in the class ApacheCrunch::ProcedureRoutine

Instance Method Details

#_key_for(val, bucket_width) ⇒ Object

Determines the key for the distribution hash given the value and step



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# File 'lib/procedure_dsl.rb', line 163

def _key_for(val, bucket_width)
    (val.to_i / bucket_width) * bucket_width
end

#execute(bucket_width, &blk) ⇒ Object 



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# File 'lib/procedure_dsl.rb', line 142

def execute(bucket_width, &blk)
    dist = {}
    while @_current_entry = @_log_parser.next_entry
        val = instance_eval(&blk)
        k = _key_for(val, bucket_width)
        if dist.key?(k)
            dist[k] += 1
        else
            dist[k] = 1
        end
    end

    # Backfill keys for which we didn't find a value
    0.step(dist.keys.max, bucket_width).each do |k|
        dist[k] = 0 unless dist.key?(k)
    end

    dist
end