Weighted Average Aggregation Usageedit

A single-value metrics aggregation that computes the weighted average of numeric values that are extracted from the aggregated documents. These values can be extracted either from specific numeric fields in the documents. When calculating a regular average, each datapoint has an equal "weight" i.e. it contributes equally to the final value. Weighted averages, on the other hand, weight each datapoint differently. The amount that each datapoint contributes to the final value is extracted from the document, or provided by a script.

Note

Only available in Elasticsearch 6.4.0+

Be sure to read the Elasticsearch documentation on Weighted Avg Aggregation

Fluent DSL exampleedit

a => a
.WeightedAverage("weighted_avg_commits", avg => avg
    .Value(v => v.Field(p => p.NumberOfCommits).Missing(0))
    .Weight(w => w.Script("doc.numberOfContributors.value + 1"))
    .ValueType(ValueType.Long)
)

Object Initializer syntax exampleedit

new WeightedAverageAggregation("weighted_avg_commits")
{
    Value = new WeightedAverageValue(Field<Project>(p => p.NumberOfCommits))
    {
        Missing = 0
    },
    Weight = new WeightedAverageValue(new InlineScript("doc.numberOfContributors.value + 1")),
    ValueType = ValueType.Long
}

Example json output. 

{
  "weighted_avg_commits": {
    "weighted_avg": {
      "value": {
        "field": "numberOfCommits",
        "missing": 0.0
      },
      "weight": {
        "script": {
          "source": "doc.numberOfContributors.value + 1"
        }
      },
      "value_type": "long"
    }
  }
}

Handling Responsesedit

response.ShouldBeValid();
var commitsAvg = response.Aggregations.WeightedAverage("weighted_avg_commits");
commitsAvg.Should().NotBeNull();
commitsAvg.Value.Should().BeGreaterThan(0);