# How to calculate the average length and FA value of fiber bundles

**URL:** https://discourse.slicer.org/t/how-to-calculate-the-average-length-and-fa-value-of-fiber-bundles/16225
**Category:** SlicerDMRI
**Tags:** diffusion
**Created:** [February 26, 2021, 1:26am UTC](https://discourse.slicer.org/t/how-to-calculate-the-average-length-and-fa-value-of-fiber-bundles/16225 "2021-02-26T01:26:15Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![slicer365](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/slicer365/32/67549_2.png) [@slicer365](https://discourse.slicer.org/u/slicer365)
#### Post date: [February 26, 2021, 1:26am UTC](https://discourse.slicer.org/t/how-to-calculate-the-average-length-and-fa-value-of-fiber-bundles/16225/1 "2021-02-26T01:26:15Z")

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How to calculate the average length and FA value of fiber bundles like this picture?For example, if I set a label or model and get the corresponding fiber bundle, how to calculate the average length and FA value of the fiber bundle contained in this label or model

 ![捕获](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/2/f/2f09b057b1c11c1506c6e44c1f184ff934072c04.jpeg)