> For the complete documentation index, see [llms.txt](https://docs.augelab.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.augelab.com/function-blocks/blocks-reference/data-logic/logic/logic-operations.md).

# Logic Operations

This function block evaluates logical and comparison operations over one or more inputs. Use it to combine boolean checks, compare numeric values, or reduce multiple conditions into a single true/false output.

## 📥 Inputs <a href="#inputs" id="inputs"></a>

`Generic` Accepts any data type. Multiple inputs can be connected and evaluated together.

`Generic` Accepts any data type. (Second default socket; more inputs may be added)

## 📤 Outputs <a href="#outputs" id="outputs"></a>

`Boolean` The resulting true/false value after evaluating the selected logic or comparison.

## 🕹️ Controls <a href="#controls" id="controls"></a>

`Method` Select which logical or comparison operation to apply to the inputs. Common methods include AND, OR, GREATER, SMALLER, EQUALS, and NOT EQUALS.

## 🎨 Features <a href="#features" id="features"></a>

`Multi-input support` Evaluate two or more inputs together, not limited to only two values.

`Flexible input types` Inputs are generic so you can feed numbers, booleans, lists, or other values depending on your scenario.

`Context-aware comparisons` Comparison methods work for both pairwise comparisons and for checking the first input against multiple others.

## 📝 Usage Instructions <a href="#usage" id="usage"></a>

1. Connect one or more values to the inputs. Typical sources are counts, measurement numbers, or boolean signals from other function blocks.
2. Choose the desired operation from the `Method` combobox.
3. The block outputs a single `Boolean` that represents the result of the selected logical/comparison operation.

Examples:

* Use `Method` set to AND when you need all conditions to be true for a pass.
* Use GREATER when checking whether a measured value is higher than a threshold or higher than multiple reference values.
* Use EQUALS to verify that several inputs are identical.

## 📊 Evaluation Behavior <a href="#evaluation" id="evaluation"></a>

* AND returns true only if every input value evaluates to true.
* OR returns true if any input evaluates to true.
* GREATER compares the first input against the second; when more inputs are provided, it checks whether the first input is greater than each of the others.
* SMALLER behaves like GREATER but tests if the first input is lesser.
* EQUALS returns true when the first input equals all other inputs.
* NOT EQUALS returns true if any of the other inputs differ from the first input.

## 💡 Tips and Tricks <a href="#tips-and-tricks" id="tips-and-tricks"></a>

* Combine with detection and counting blocks
  * Connect `Object Count` from `Object Detection` or `Object Detection - Custom` to check if an object count is above a threshold using GREATER, then trigger `Record Video` or `Image Logger`.
* Use with tracking results
  * Feed tracking outputs like `Position - ID List` from `Object_Detection_Tracker` into this block to create rules such as "is any tracked object present" using OR or NOT EQUALS.
* Mask / safety logic
  * Combine outputs from `Mask Detection` or `Safety Equipment Detection` with AND to assert multiple safety conditions are met before raising an alarm or saving a frame.
* Pre-checks and flow control
  * Use this block with `Is None` or `Replace None` to validate inputs before downstream processing. For example, ensure image data exists and a detector produced results before continuing.
* Measurement comparisons
  * Feed numeric outputs from `Measure Position Distance`, `Get Dimension`, or `Mean Value of Image` to GREATER/SMALLER methods to create pass/fail conditions for quality checks.
* Use in automation flows
  * Chain the boolean result to `Led Output`, `Write Text On Image`, `CSV Export`, or `MQTT Publish` to act on detection or measurement outcomes.

## 🛠️ Troubleshooting <a href="#troubleshooting" id="troubleshooting"></a>

* Unexpected false results
  * Check the data types flowing into the inputs. Convert or normalize values (for example, use `Round` or `String Operations`) so comparisons behave as expected.
* Comparisons with multiple inputs behave differently
  * Remember that GREATER and SMALLER compare the first input against the others. If you need pairwise comparisons, feed appropriate pairs or use multiple Logic Operations blocks.
* No output or stuck flow
  * Ensure at least one input is connected or valid. Use `Is None` or `Replace None` to guard against missing values.