Package org.zkoss.pivot.impl.calc
Interface Context<C extends Context<C>>
- All Known Implementing Classes:
MinMaxContext,ProductContext,SumCountContext,VarianceContext
public interface Context<C extends Context<C>>
The context to hold intermediate result of an aggregation. For example,
to calculate arithmetic average, we need to accumulate SUM and COUNT.
It is provable that if an aggregation over a collection is order independent
and its computation can be carried out via a context data type with a binary
operator, then the context can also be merged from contexts over a partition
of the original collection.
- Author:
- simonpai
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Method Summary
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Method Details
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add
Add an item into the aggregation. -
merge
Merge from another context of the same type.
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