# BNNSGraphContextExecute(_:_:_:_:_:_:) Executes the specified function with the given context. ``` func BNNSGraphContextExecute(_ context: bnns_graph_context_t, _ function: UnsafePointer?, _ argument_count: Int, _ arguments: UnsafeMutablePointer, _ workspace_size: Int, _ workspace: UnsafeMutablePointer?) -> Int32 ``` ## Parameters `context` The graph context. You may only use this context on a single thread at a time. `function` The function. Specify as `nil` if the graph only contains one function. `argument_count` The number of elements in the `arguments` array. `arguments` An array of `bnns_graph_argument_t` objects that supply the input data and the outputs. Use the [`BNNSGraphGetArgumentPosition(_:_:_:)`](/documentation/Accelerate/BNNSGraphGetArgumentPosition(_:_:_:)) to derive the argument positions for this parameter. If you supply unallocated output arguments, this function allocates the required memory and reuses that memory for future executions. `workspace_size` The size of the workspace. Call [`BNNSGraphContextGetWorkspaceSize(_:_:)`](/documentation/Accelerate/BNNSGraphContextGetWorkspaceSize(_:_:)) to get the required size or pass `0` and a null `workspace` parameter to specify that this function allocates its own workspace. `workspace` The temporary workspace that the function uses during execution. Call [`BNNSGraphContextGetWorkspaceSize(_:_:)`](/documentation/Accelerate/BNNSGraphContextGetWorkspaceSize(_:_:)) to get the required size or pass `nil` and a zero `workspace_size` parameter to specify that this function allocates its own workspace. ## Return Value `0` on success, nonzero on failure. ## Discussion If the underlying model contains dynamic shaped inputs or outputs, you must set these prior to calling this routine with either [`BNNSGraphContextSetDynamicShapes(_:_:_:_:)`](/documentation/Accelerate/BNNSGraphContextSetDynamicShapes(_:_:_:_:)) or [`BNNSGraphContextSetBatchSize(_:_:_:)`](/documentation/Accelerate/BNNSGraphContextSetBatchSize(_:_:_:)). Don’t modify these shapes during execution. This function doesn’t perform memory allocation if your code meets the following conditions: - The workspace isn’t `nil`. - The graph doesn’t contain tensors that BNNS couldn’t bound prior to calling this function. - The arguments array doesn’t contain any new shape information. - The code provides all output storage. The following code executes the graph with the [`BNNSTensor`](/documentation/Accelerate/BNNSTensor) structures `inputTensor` and `outputTensor` as the input and output arguments, respectively: ```swift withUnsafeMutablePointer(to: &inputTensor) { input in withUnsafeMutablePointer(to: &outputTensor) { output in var inputArgument = bnns_graph_argument_t() inputArgument.tensor = input var outputArgument = bnns_graph_argument_t() outputArgument.tensor = output var arguments = [outputArgument, inputArgument] BNNSGraphContextSetArgumentType(context, BNNSGraphArgumentTypeTensor) BNNSGraphContextExecute(context, nil, 2, &arguments, 0, nil) } } ``` --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)