---
title: "apply(input:)"
framework: accelerate
role: symbol
role_heading: Instance Method
path: "accelerate/vdsp/biquad/apply(input:)"
---

# apply(input:)

Applies a single- or double-precision single-channel or multichannel biquad IIR filter, returning the filtered signal.

## Declaration

```swift
mutating func apply<U>(input: U) -> [T] where T == U.Element, U : AccelerateBuffer
```

## See Also

### Instance methods

- [apply(input:output:)](accelerate/vdsp/biquad/apply(input:output:).md)