# Struggling to identify a coordinate from the original volume to the new resampled euler transform volume (with offset)
**URL:** https://discourse.itk.org/t/struggling-to-identify-a-coordinate-from-the-original-volume-to-the-new-resampled-euler-transform-volume-with-offset/3515
**Category:** Beginner Questions
**Created:** [October 6, 2020, 7:05pm UTC](https://discourse.itk.org/t/struggling-to-identify-a-coordinate-from-the-original-volume-to-the-new-resampled-euler-transform-volume-with-offset/3515 "2020-10-06T19:05:07Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@Helena](https://discourse.itk.org/u/Helena)
#### Post date: [October 6, 2020, 7:05pm UTC](https://discourse.itk.org/t/struggling-to-identify-a-coordinate-from-the-original-volume-to-the-new-resampled-euler-transform-volume-with-offset/3515/1 "2020-10-06T19:05:08Z")
I have a volume that I resample using img\_center , and a transform matrix = [0.814277854168591, 0.58047530198157, 0, -0.58047530198157, 0.814277854168591, 0, 0, 0, 1] via euler 3d transformation.
I would like to extract a coordinate at [330,117,172] (within array) but in the new resampled\_volume however, as the size is the same as the original volume with rotation the coordinate has changed, I canβt find a way to extract the correct position and have tried multiple techniques any advice would be much appreciated π
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### Author:  [@zivy](https://discourse.itk.org/u/zivy)
#### Post date: [October 6, 2020, 7:26pm UTC](https://discourse.itk.org/t/struggling-to-identify-a-coordinate-from-the-original-volume-to-the-new-resampled-euler-transform-volume-with-offset/3515/2 "2020-10-06T19:26:01Z")
Hello @Helena,
When working with transformations you need to work with physical points and not indexes into the image array. The relevant image methods are [TransformIndexToPhysicalPoint](https://itk.org/Doxygen/html/classitk_1_1ImageBase.html#ae2e113c2ff7bab1a145c27a30584a2ac) and [TransformPhysicalPointToIndex](https://itk.org/Doxygen/html/classitk_1_1ImageBase.html#ae46118e0a604c11e6f1170da7c478f81). You start with the indexes, get the physical point, transform that and then get the indexes for the transformed point.
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### Author:  [@Helena](https://discourse.itk.org/u/Helena)
#### Post date: [October 7, 2020, 10:33am UTC](https://discourse.itk.org/t/struggling-to-identify-a-coordinate-from-the-original-volume-to-the-new-resampled-euler-transform-volume-with-offset/3515/3 "2020-10-07T10:33:24Z")
Hello @zivy Thank you for the response i followed the instructions and I still do not get the correct position, unless i inverse the transform but then I do not get the correct transformed volume. I can share the volume file and coordinate information I am trying to extract, maybe i am missing something.
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### Author:  [@dzenanz](https://discourse.itk.org/u/dzenanz)
#### Post date: [October 7, 2020, 6:22pm UTC](https://discourse.itk.org/t/struggling-to-identify-a-coordinate-from-the-original-volume-to-the-new-resampled-euler-transform-volume-with-offset/3515/4 "2020-10-07T18:22:55Z")
Transforms in ITK transform from moving space to fixed space. To go from fixed to moving you need the inverse.
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### Author:  [@Helena](https://discourse.itk.org/u/Helena)
#### Post date: [October 7, 2020, 6:35pm UTC](https://discourse.itk.org/t/struggling-to-identify-a-coordinate-from-the-original-volume-to-the-new-resampled-euler-transform-volume-with-offset/3515/5 "2020-10-07T18:35:29Z")
Yes thank you I worked it out now π