---
title: activity
framework: musicunderstanding
role: symbol
role_heading: Instance Property
platforms: [iOS 27.0+, iPadOS 27.0+, Mac Catalyst 27.0+, macOS 27.0+, tvOS 27.0+, visionOS 27.0+, watchOS 27.0+]
path: musicunderstanding/instrumentactivityresult/activity
---

# activity

The activity level of each instrument over time, as values from 0.0 to 1.0.

## Declaration

```swift
let activity: [InstrumentActivityResult.Instrument : [MusicUnderstandingSession.TimedValue<Float>]]
```