# calculating distance map and getting text file
**URL:** https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157
**Category:** Support
**Created:** [February 23, 2018, 2:40am UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157 "2018-02-23T02:40:04Z")
**Posts on this page:** 12
**Page:** 1
### Author:  [@nodi](https://discourse.slicer.org/u/nodi)
#### Post date: [February 23, 2018, 2:40am UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/1 "2018-02-23T02:40:04Z")
hello.
I’m new to Slicer. I want to use this filter: ApproximateSignedDistanceMapImageFilter. to calculate the distance of each point to the boundary after doing segmentation.
How can I get the distance map as a text file to recall it again for other purposes?
Thank you.
---
### Author:  [@nodi](https://discourse.slicer.org/u/nodi)
#### Post date: [February 23, 2018, 10:10pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/2 "2018-02-23T22:10:23Z")
Can somebody help please?
---
### Author:  [@pieper](https://discourse.slicer.org/u/pieper)
#### Post date: [February 23, 2018, 10:36pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/3 "2018-02-23T22:36:59Z")
Hi -
You can run that filter through SimpleFilters
[https://www.slicer.org/wiki/Documentation/Nightly/Modules/SimpleFilters](https://www.slicer.org/wiki/Documentation/Nightly/Modules/SimpleFilters)
You can save the result as an regular volume file that you can reload (in binary not in ascii text, but you could convert it outside slicer if you want text).
Hope that helps,
Steve
---
### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [February 23, 2018, 10:45pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/4 "2018-02-23T22:45:01Z")
Also note that you can get Hausdorff distance and even full surface error distribution from Segment Comparison module in SlicerRT extension:
[https://www.slicer.org/wiki/Documentation/Nightly/Modules/SegmentComparison](https://www.slicer.org/wiki/Documentation/Nightly/Modules/SegmentComparison)
---
### Author:  [@nodi](https://discourse.slicer.org/u/nodi)
#### Post date: [February 25, 2018, 9:57pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/5 "2018-02-25T21:57:43Z")
Thank you for respond but what do you mean by
> [@pieper](#):
>
> convert it outside slicer if you want text
?
---
### Author:  [@nodi](https://discourse.slicer.org/u/nodi)
#### Post date: [February 25, 2018, 9:59pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/6 "2018-02-25T21:59:34Z")
Thank you Lasso.
How can I use the maximum distance value as a radius to draw a sphere?
---
### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [February 25, 2018, 11:08pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/7 "2018-02-25T23:08:29Z")
You can expand your segment by a specified margin in Segment Editor module, using Margin effect.
---
### Author:  [@nodi](https://discourse.slicer.org/u/nodi)
#### Post date: [February 26, 2018, 8:58pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/8 "2018-02-26T20:58:07Z")
I have read about the Segment Comparison. it compare between 2 models or segments. but I want to find the max distance for each voxel on tumor to the edge (boundary) of the tumor.
---
### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [February 26, 2018, 10:51pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/9 "2018-02-26T22:51:10Z")
That’s a distance map that you can compute using Simple Filters module as described above.
Why do you need the distance map? For segmentation or registration accuracy assessment?
---
### Author:  [@nodi](https://discourse.slicer.org/u/nodi)
#### Post date: [February 27, 2018, 10:43pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/10 "2018-02-27T22:43:30Z")
for drawing spheres based on the distances.
---
### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [February 27, 2018, 10:59pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/11 "2018-02-27T22:59:30Z")
> [@nodi](#):
>
> for drawing spheres based on the distances.
I mean what is the end goal - the clinical problem and the solution that you are working towards?
---
### Author:  [@nodi](https://discourse.slicer.org/u/nodi)
#### Post date: [February 28, 2018, 5:23pm UTC](https://discourse.slicer.org/t/calculating-distance-map-and-getting-text-file/2157/12 "2018-02-28T17:23:39Z")
to define the position of the shot (radiotherapy)