---
title: promql.linearRegression() function
description: promql.linearRegression() implements linear regression functionality required to implement PromQL’s deriv() and predict_linear() functions.
url: https://docs.influxdata.com/flux/v0/stdlib/internal/promql/linearregression/
estimated_tokens: 660
product: Flux
version: v0
---

# promql.linearRegression() function

-   Flux 0.47.0+
-   View InfluxDB support

`promql.linearRegression()` implements linear regression functionality required to implement PromQL’s [`deriv()`](https://prometheus.io/docs/prometheus/latest/querying/functions/#deriv) and [`predict_linear()`](https://prometheus.io/docs/prometheus/latest/querying/functions/#predict_linear) functions.

**Important**: The `internal/promql` package is not meant for external use.

##### Function type signature

```js
(
    <-tables: stream[{A with _value: float, _time: time, _stop: time}],
    ?fromNow: float,
    ?predict: bool,
) => stream[{B with _value: float}]
```

For more information, see [Function type signatures](/flux/v0/function-type-signatures/).

## Parameters

### tables

Input data. Default is piped-forward data (`<-`).

### predict

Output should contain a prediction.

### fromNow

Time as a floating point value.