reduce

Reduce values of a sequence to a single value using a custom javascript accumulating function. The reduction result is the last accumulated value.

See also map.

Syntax

reduce(accumulator[,initialValue])

Parameter	Description
accumulator	Accumulating javascript function called for each value (with arguments: accumulated value, value and index of the value in the sequence) and that returns the new accumulated value. Note that if the accumulated value resulting of the function call is null, it is not applied to the final reduction result.
initialValue	Optional value to be used to initialize the accumulated value. If not provided, the accumulated value will be initialized with the first not null value of the sequence (thus in this case the accumulating function is not called during this initialization phase).

Examples

Reduce as sequence of measures to their sum:

$('Words').reduce(function(acc, value, index) {
  return acc.plus(value);
})

Reduce a sequence of measures to their average value initialized to 0:

$('SequenceVar').reduce(function(acc, value, index) {
  return acc.multiply(index).plus(value).div(index+1);
}, 0)