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# vDSP_biquadm_SetActiveFilters

Activates or deactivates individual sections in a single-precision, multichannel biquadratic filter.

```
extern void vDSP_biquadm_SetActiveFilters(vDSP_biquadm_Setup __setup, const _Bool *__filter_states);
```

## Parameters

`__setup`

The biquadratic filter setup object that the function updates.

`__filter_states`

An array of Boolean values, each of which corresponds to a section in the biquadratic filter.

## Discussion

For each section in a multichannel biquadratic filter, the corresponding Boolean value in `filter_states` sets the section to active or inactive. The apply function removes inactive filters from the processing chain. The biquadratic filter retains the state of inactive sections for future use.

---

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