---
title: Use the Gaussian Filter Function
slug: litmusedge/how-to-guides/analytics-guides/gaussian-filter-function
description: Learn how to use the Gaussian Filter function in Analytics. 
docTags: 
createdAt: 2024-02-29T17:07:05.771Z
---

You can use the Gaussian Filter function to calculate a smoothed value for each point by considering its adjacent data points. 

It is factored by a simple Gaussian digital filter, which depends on the distance from the mean, ensuring a natural weighting of surrounding values.

# Understanding Gaussian Function 

The following information describes this function:

- Calculates the mean, standard deviation, and variance of a set of values within a specific window.
- Determines a coefficient using the formula `1 / (sqrt(2 * PI) * deviation)`
- Computes the exponential part with `exp(-1/2 * ((current - mean) / deviation)^2)`
- The Gaussian Function is derived by multiplying the coefficient with the exponential part.
- The process results in a filtered value that smooths or blurs the original data, applying a natural weight based on proximity to the mean.

# User Scenario

Review the following scenario for the Gaussian Filter function. Then, you will simulate PLC data and calculate the filtered values.

In a precision manufacturing facility specializing in aerospace components, high-resolution cameras are employed to inspect the surface of parts for microscopic flaws. These inspections generate vast amounts of image data, where even the smallest imperfection can signal a potential failure in critical aerospace systems. 

We apply the Gaussian Filter function to images to reduce noise and lighting changes that can hide defects. This helps the inspection algorithms to find any problems with a component.

#  Step 1: Add a Device

Follow the steps to [Connect a device](docId\:pal6ABPZbrimdU9LvGJ30) and configure the following parameters:

- **Device Type**: Simulator
- **Driver Name**: Generator
- **Enable Alias Topics**: Select the checkbox. 

# Step 2: Add Tags

After connecting the device, add the following tag. See [Add Tags](docId\:XgWOkQbTPevII7OR82LL0) to learn more. 

## Tag 1: input1

- **Name**: Select **S - Random value generator**
- **Value Type:** Select **float64**
- **Polling Interval**: Enter **1**
- **Tag Name**: Enter **input1**
- **Min\_value**: Enter **101**
- **Max\_value**: Enter **199**

# Step 3: Create Analytics Flows

You can now create the analytics flows using data from the device and tag you previously created. 

**To create an analytics flow with the Gaussian Filter Processor function:**

1. In Litmus Edge, navigate to **Analytics**. 
2. On the analytics canvas, click** Add processor**. 
   The *Create a processor* dialog box displays. 
   ::Image[]{src="https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/ZdcpDTjKPrLwdKeFw6LWq_base-conversionadd-processor.png" size="80" width="1244" height="452" caption="The Add processor option" position="center" showCaption="true"}
3. Select **DataHub Subscribe**.
4. In the **Topic **field, click the **Search **icon, select the device you previously created, and then select the alias topic for the **input1 **tag. 
   ![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/AdCgZcKlrYLXkOnUTBkWY_a.png "Create a Processor dialog box")
5. Click **Save**.
6. Click **Add processor** again and select the **Gaussian Filter **processor.
   The *Edit a Processor* dialog box appears.
   - **Window Size:** Enter a value that represents the range to apply the gaussian digital function. For this example, we input a value of **30**.
   - **Number of Deviations: **Number of deviations to use for the calculations. For this example, we input a value of **1**.
   - **TimeInterval: **If you know your input is going to publish at the expected interval, it is better to disable this timer by entering **0** in the field.
   - Click **Save**.
     ![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/b8UQ_jUu5sus9-FZMkQJK_image.png "Edit a Processor dialog box")
7. Connect the *DataHub Subscribe* processor (tag: *input1*) to the *Gaussian Filter *processor with a wire and use the **events **connection.
8. On the analytics canvas, click **Save**.
   The configured analytics flows should look like the following: 

![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/Ix7efScZDSQNWV30jVS4k_image.png "Completed Flows Canvas")

# Step 4: View Output of Processor

Click the **View **icon in the *Gaussian Filter *processor to view the output values.

The Gaussian Filter output yielded a filtered value of **1.16882172100685** with a coefficient of **0.013888633443174866  **and exponential of **0.6947003584251287**.

![](https://api.archbee.com/api/optimize/SSUUxKZUk9bFTEPNn_6Zo/Gg0G144LZoH6JZeSXH3w-_image.png "Output of Gaussian Filter")