---
title: "system.math.kurtosis"
description: "Calculates the kurtosis of a sequence of values."
---

# system.math.kurtosis

> Calculates the kurtosis of a sequence of values.

This function is used in **Python Scripting**.

## Description
Calculates the kurtosis of a sequence of values. Kurtosis measures if data is peaked or flat relative to normal distribution. A set of data with high kurtosis will have distinct peaks near the mean, while a set of data with low kurtosis will have a flat top near the mean. Uniform distribution is typically a flat line.

Returns NaN (Not a Number) if passed an empty sequence measure of whether the data are heavy-tailed or light-tailed of a given distribution.

## Client Permission Restrictions
This scripting function has no [Client Permission](../../../ignition-modules/vision/vision-project-properties/vision-project-properties.md#vision-permissions-properties) restrictions.

## Syntax
`system.math.kurtosis(values)`

### Parameters
Type | Parameter | Description 
------- | ------- | ------
List[Float] | `values` | A sequence of numerical values. Accepts both integers and floats. The sequence may not contain None type values. However, passing a None type object instead of a sequence of numerical values will return NaN. Requires at least four items in the list.

### Returns
**Float** - The kurtosis, or NaN if the input was empty or null. Additionally, returns NaN if the values returned fewer than four values.

### Scope
Gateway, Vision Client, Perspective Session

## Code Examples
```python title="Example #1"
# Create a List of values.
values = [3.5, 5.6, 7.8, 7.4, 3.8]
  
# Prints the resulting value.
print system.math.kurtosis(values)
```