List Operations

This function block provides a collection of common list manipulations in a single, easy-to-use interface. Choose an operation from the dropdown and the block will adapt its inputs and outputs so you can work with lists (create, query, modify, combine, filter and more) without writing any code.

📥 Inputs

The available inputs change dynamically based on the selected operation.

List A generic list input used by many operations.

Element A single element to append, remove, or search for.

Index An integer index for operations like Get, Set, Insert or Pop.

List(s) When combining multiple lists (Pair) this socket accepts a list of lists.

List (String) A single text input used by the Create method to build a list from a comma-separated string.

(Other input socket names appear as needed by the chosen method.)

📤 Outputs

The outputs are also dynamic and reflect the chosen method.

List Returned list after mutation operations (e.g., append, extend, remove).

Filtered List Result of a filter operation.

Element An individual element returned by Get, Min, Max, etc.

Size Length returned by the Len method.

Index Index of an element for the Index method.

(Additional output sockets appear depending on the method selected.)

🕹️ Controls

Select a method A dropdown with a small action button. Choose the desired list operation (examples: append, extend, filter, create, len, min, max, slice, pair). The block updates sockets automatically when you change this selection.

Info A small text area that displays usage hints for the selected method (for example, reminding you that filter conditions must be a boolean list of the same length).

🎨 Features

• Dynamic sockets: inputs and outputs are created or removed automatically when you pick a method, keeping the interface clean.

• Wide operation set: supports creation, querying, modification and combining of lists (append, extend, insert, pop, remove, filter, slice, sort, reverse, sum, min/max, index, set, pair, and more).

• Built-in validation: warns when indexes are out of bounds or when list sizes do not match for operations like filter or pair.

• Create from text: build a list quickly from a comma-separated string using the Create method.

⚙️ Running mechanism

1. Choose a method using the Select a method control.

2. The block updates its input and output sockets to match the selected operation.

3. Provide the required inputs by connecting other blocks or entering values.

4. When the scenario runs, the block performs the chosen list operation and provides the result on the specified output sockets.

5. If inputs are invalid (e.g., mismatched sizes, invalid index), the block shows an error message and returns a safe fallback where appropriate.

📝 Usage instructions

1. Open the block and pick the desired operation from Select a method.

2. Inspect the displayed Info text for quick guidance about that method.

3. Connect the appropriate inputs (for example, connect a list and an element for Append).

4. Run the scenario and read results from the output sockets that appear for the chosen method.

💡 Tips and Tricks

Create Use with a String Input block to let users type comma-separated items, then convert them into a list automatically.

Filter and Filter Inverse When filtering data, produce the condition list with logical blocks such as Equals, Greater, or Less and then feed that boolean list into this block to extract matching items.

Pair Useful to combine parallel data streams. Pair works well with outputs from Object Detection or Object Detection - Custom when you have parallel lists (for example, positions and sizes) and want them zipped together for downstream logging or export.

Get, Index, Min, Max Combine with Get Element, Exclude Nones, or Replace None to sanitize inputs before querying or aggregating list values.

Sum, Len Use with Scope or CSV Export to collect numerical summaries for plotting or logging.

Slice When processing a batch of items, combine with Debatch or Batch Processing to iterate and process sublists.

General

• Use Data Memory when you want to hold a list steady until an explicit update arrives.

• Create logging or export pipelines: after restructuring lists here, send results to Data to JSON or CSV Export for external storage.

• When building lists from textual sources, use Find Substring and String Merge to prepare strings before using the Create method.

(have these related blocks ready in your workspace to build robust pipelines)

🛠️ Troubleshooting

Filter and size mismatch If you see an error about unequal sizes, make sure the condition list has the same number of elements as the data list. Use Get Batch Size or Len to diagnose sizes.

Index out of range For methods that take an index (Get, Set, Insert, Pop), verify index bounds before connecting. Use Len or Get Batch Size to obtain valid ranges.

Unexpected types Some operations expect numeric or comparable items (for Sum, Min, Max, Sort). Use Replace None and Exclude Nones to clean the list first.

Creating lists from text When using Create, ensure items are comma-separated. Extra whitespace is trimmed automatically, but non-numeric tokens remain strings — double-check with Find Substring or String Operations if you need further parsing.

If you run into persistent issues, check the Info hint for the selected method — it often contains quick, method-specific guidance.