> ## Documentation Index
> Fetch the complete documentation index at: https://www.algolia.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Apply a variant's captured settings to the control index

> Applies the captured settings of the given variant to the control index.

**Required ACL:** `analytics`, `editSettings`

The settings must first be captured with the `saveVariantSettings` operation. To revert previously applied settings on the control index, use this operation with the control variant (variant 1).

Settings can be applied up to 14 days after the A/B test ends, and reverted up to 15 days after. Later requests return `400`.

Each set of captured settings can only be applied once, and settings that were reverted can't be applied again. Both cases return `400`.

The control index must not be in use by an active A/B test. Otherwise, the request returns `422`.

## Usage

```cs C# theme={"system"}
// Initialize the client
var client = new AbtestingV3Client(
  new AbtestingV3Config(
    "ALGOLIA_APPLICATION_ID",
    "ALGOLIA_API_KEY",
    "ALGOLIA_APPLICATION_REGION"
  )
);

// Call the API
await client.ApplyVariantSettingsAsync(42, 2);
```

```dart Dart theme={"system"}
// Initialize the client
final client = AbtestingV3Client(
    appId: 'ALGOLIA_APPLICATION_ID',
    apiKey: 'ALGOLIA_API_KEY',
    region: 'ALGOLIA_APPLICATION_REGION');

// Call the API
await client.applyVariantSettings(
  id: 42,
  variantId: 2,
);
```

```go Go theme={"system"}
// Initialize the client with your application region, eg. abtestingV3.ALGOLIA_APPLICATION_REGION
client, err := abtestingV3.NewClient("ALGOLIA_APPLICATION_ID", "ALGOLIA_API_KEY", abtestingV3.US)
if err != nil {
  // The client can fail to initialize if you pass an invalid parameter.
  panic(err)
}

// Call the API
err = client.ApplyVariantSettings(client.NewApiApplyVariantSettingsRequest(
  42, 2))
if err != nil {
  // handle the eventual error
  panic(err)
}
```

```java Java theme={"system"}
// Initialize the client
AbtestingV3Client client = new AbtestingV3Client("ALGOLIA_APPLICATION_ID", "ALGOLIA_API_KEY", "ALGOLIA_APPLICATION_REGION");

// Call the API
client.applyVariantSettings(42, 2);
```

```js JavaScript theme={"system"}
// Initialize the client
// Replace 'us' with your Algolia Application Region
const client = algoliasearch('ALGOLIA_APPLICATION_ID', 'ALGOLIA_API_KEY').initAbtestingV3({ region: 'us' });

// Call the API
await client.applyVariantSettings({ id: 42, variantId: 2 });
```

```kotlin Kotlin theme={"system"}
// Initialize the client
val client =
  AbtestingV3Client(
    appId = "ALGOLIA_APPLICATION_ID",
    apiKey = "ALGOLIA_API_KEY",
    region = "ALGOLIA_APPLICATION_REGION",
  )

// Call the API
client.applyVariantSettings(id = 42, variantId = 2)
```

```php PHP theme={"system"}
// Initialize the client
$client = AbtestingV3Client::create('ALGOLIA_APPLICATION_ID', 'ALGOLIA_API_KEY', 'ALGOLIA_APPLICATION_REGION');

// Call the API
$client->applyVariantSettings(
    42,
    2,
);
```

```python Python theme={"system"}
# Initialize the client
# In an asynchronous context, you can use AbtestingV3Client instead, which exposes the exact same methods.
client = AbtestingV3ClientSync(
    "ALGOLIA_APPLICATION_ID", "ALGOLIA_API_KEY", "ALGOLIA_APPLICATION_REGION"
)

# Call the API
client.apply_variant_settings(
    id=42,
    variant_id=2,
)
```

```ruby Ruby theme={"system"}
# Initialize the client
client = Algolia::AbtestingV3Client.create("ALGOLIA_APPLICATION_ID", "ALGOLIA_API_KEY", "ALGOLIA_APPLICATION_REGION")

# Call the API
client.apply_variant_settings(42, 2)
```

```scala Scala theme={"system"}
// Initialize the client
val client = AbtestingV3Client(
  appId = "ALGOLIA_APPLICATION_ID",
  apiKey = "ALGOLIA_API_KEY",
  region = Option("ALGOLIA_APPLICATION_REGION")
)

// Call the API
Await.result(
  client.applyVariantSettings(
    id = 42,
    variantId = 2
  ),
  Duration(100, "sec")
)
```

```swift Swift theme={"system"}
// Initialize the client
let client = try AbtestingV3Client(appID: "ALGOLIA_APPLICATION_ID", apiKey: "ALGOLIA_API_KEY", region: .us)

// Call the API
try await client.applyVariantSettings(id: 42, variantId: 2)
```

> **[See the full API reference](https://www.algolia.com/doc/rest-api/abtesting-v3/apply-variant-settings.md)**
>
> For more details about input parameters
> and response fields.