Get Element

This function block extracts a single item from a provided list (batch) by using an index value. It is useful when you need to pick one element from a collection and feed it into downstream blocks.

📥 Inputs

Batch A list or batch of values (images, numbers, texts, etc.) from which an element will be retrieved.

Index The index position (zero-based) indicating which element to return from the batch.

📤 Outputs

Generic The selected element from the batch. The returned type matches the element type inside the input batch.

🕹️ Controls

This function block has no interactive widgets. It works by reading the provided input sockets each evaluation step.

🎨 Features

• Simple and direct extraction of one element from a list or batch.

• Works with any generic data type carried inside the batch (images, numbers, strings, shapes, etc.).

• Designed for straightforward integration in flow where single-item processing is needed.

📝 Usage Instructions

1. Provide a list or batch to the Batch input.

2. Provide the element position (zero-based) to the Index input.

3. The block outputs the element at the requested position on its Generic output.

4. If you provide a batch with dynamic length, ensure the index value is valid to avoid unexpected results.

📊 Evaluation

On each run, the block reads the current Batch and the Index values, then forwards the element at that index to the output. If the index refers to a single value, a single element is returned; when combined with batching flow control, it can be used to select specific items for further processing.

💡 Tips and Tricks

• Use Batch Processing before this block when you want to feed grouped or streamed data and reduce memory usage.

• Combine with Debatch to convert a batch into individual items and then use Get Element to pick a specific item from that stream.

• Use Get Batch Size to verify the batch length before selecting an index; this prevents out-of-range selections.

• Use Is None and Replace None after this block to handle missing values gracefully.

• Use Data Memory to freeze or cache a batch and keep the same data available while experimenting with different index values.

• Use Debug Input to inspect the batch or index when results are unexpected.

• When building indexed image pipelines, combine with visualization blocks like Show Image to preview the selected image element.

🛠️ Troubleshooting

• If you receive unexpected or empty output, confirm the Batch actually contains elements and that Index is within the valid range (0..length-1).

• If the pipeline sometimes supplies None values, use Is None or Replace None to guard downstream processing.

• For workflows with changing batch sizes, always check Get Batch Size before using Index to avoid invalid access.