Exists
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package reduce
Create a existential quantifier reducer from a predicate p.
Create a existential quantifier reducer from a predicate p.
the predicate to apply to the values of the column.
Reduce the given column of values to a cell using only the indexes in given array slice.
Reduce the given column of values to a cell using only the indexes in given array slice.
indices, start, and end represent an array slice. The
following must hold:
0 <= startend <= indices.lengthstart <= endand the slice is [start:end), inclusive of start and
exclusive of end.
Let i: Int where start <= i and i < end, then
column(indices(i)) match { case Value(v) => // 1. case NA => // 2. case NM => // 3. }
the column of values is the source of the reduction
the array of column indexes to reduce over
the start of the array slice on the indices
the end of the array slice on the indices
the result of the reduction as a Cell
A Reducer that exististentially quantifies a predicate as a reduction over a collection of Cells.
This reducer will return true upon encountering the first value that is available and meaningful and applying the predicate
pto that value returns true. Otherwise, returns false.This reducer is unusual in that it will ignore NonValues, in particular, it will not propogate NM. If the predicate can be satisfied by a value that is available and meaningful elsewhere in the collection, then this reduction should still return true.
This reducer will only traverse the entire collection if it never encounters an available and meaningful value that satisfies the predicate
p.the value type of the column to reduce.
This reducer will always return precisely
Value[Boolean], rather thanCell[Boolean]. This in constrast to most reducers that will also return NonValues.ForAll