---
title: promql.promqlHour() function
description: >
  `promql.promqlHour()` implements functionality equivalent to
  [PromQL's `hour()` function](https://prometheus.io/docs/prometheus/latest/querying/functions/#hour).
menu:
  flux_v0_ref:
    name: promql.promqlHour
    parent: internal/promql
    identifier: internal/promql/promqlHour
weight: 201
---

<!------------------------------------------------------------------------------

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`promql.promqlHour()` implements functionality equivalent to
[PromQL's `hour()` function](https://prometheus.io/docs/prometheus/latest/querying/functions/#hour).

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

##### Function type signature

```js
(timestamp: float) => float
```

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

## Parameters

### timestamp
({{< req >}})
Time as a floating point value.