# ForwardBackwardResult
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The result of a forward and backward pass through the model, including computed gradients.

## Contents
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 ** lossFnOutputs **   <a name="sagemakertrainingsession-Type-ForwardBackwardResult-lossFnOutputs"></a>
The loss function output tensors, keyed by name.  
Type: Array of string to [TensorData](API_TensorData.md) object maps  
Required: No

 ** lossFnOutputType **   <a name="sagemakertrainingsession-Type-ForwardBackwardResult-lossFnOutputType"></a>
The data type of the loss function output tensors.  
Type: String  
Required: No

 ** metrics **   <a name="sagemakertrainingsession-Type-ForwardBackwardResult-metrics"></a>
The training metrics emitted by the engine, such as loss values.  
Type: String to double map  
Required: No

 ** tokenUsage **   <a name="sagemakertrainingsession-Type-ForwardBackwardResult-tokenUsage"></a>
The token usage statistics for metering.  
Type: [TrainingTokenUsage](API_TrainingTokenUsage.md) object  
Required: No

## See Also
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For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\+\+](https://docs.aws.amazon.com/goto/SdkForCpp/sagemakertrainingsessionruntime-2025-02-10/ForwardBackwardResult) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/sagemakertrainingsessionruntime-2025-02-10/ForwardBackwardResult) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/sagemakertrainingsessionruntime-2025-02-10/ForwardBackwardResult)