--- title: promql.holtWinters() function description: > `promql.holtWinters()` implements functionality equivalent to [PromQL's `holt_winters()` function](https://prometheus.io/docs/prometheus/latest/querying/functions/#holt_winters). menu: flux_v0_ref: name: promql.holtWinters parent: internal/promql identifier: internal/promql/holtWinters weight: 201 --- `promql.holtWinters()` implements functionality equivalent to [PromQL's `holt_winters()` function](https://prometheus.io/docs/prometheus/latest/querying/functions/#holt_winters). **Important**: The `internal/promql` package is not meant for external use. ##### Function type signature ```js ( <-tables: stream[{A with _value: float, _time: time}], ?smoothingFactor: float, ?trendFactor: float, ) => stream[{B with _value: float}] ``` {{% caption %}} For more information, see [Function type signatures](/flux/v0/function-type-signatures/). {{% /caption %}} ## Parameters ### tables Input data. Default is piped-forward data (`<-`). ### smoothingFactor Exponential smoothing factor. ### trendFactor Trend factor.