Module differential_dataflow::operators::consolidate
[−]
[src]
Aggregates the weights of equal records into at most one record.
As differential dataflow streams are unordered and taken to be the accumulation of all records,
no semantic change happens via consolidate
. However, there is a practical difference between
a collection that aggregates down to zero records, and one that actually has no records. The
underlying system can more clearly see that no work must be done in the later case, and we can
drop out of, e.g. iterative computations.
Examples
This example performs a standard "word count", where each line of text is split into multiple
words, each word is converted to a word with count 1, and consolidate
then accumulates the
counts of equivalent words.
stream.flat_map(|line| line.split_whitespace()) .map(|word| (word, 1)) .consolidate();
Traits
ConsolidateExt |
An extension method for consolidating weighted streams. |