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I have a gridded dataset that has mean elevations as the centroid value. I would like to create a perpendicular transect line from lowest to highest elevation in this mountainous area. Once I have the transect, I will then pick a set of six or eight grid points from lowest to highest elevation for further analysis.

I tried looking into Creating perpendicular transects to stream at specified intervals using ArcMap, but I could not quite understand where to start. So far I know that I can draw a line perpendicular to a polygon.

How can I do this in ArcMap 10.7?

This is how I was explained about it, to draw a perpendicular transect such that I can get a set 6-8 of pixels from low to high elevation within in the study area.

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In reality my study area looks this:

enter image description here

PolyGeo
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Arthur_Morgan
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    Do you have Spatial Analyst and/or 3D Analyst licensing? What have you tried/researched? – PolyGeo Nov 10 '21 at 01:26
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    You seem to have a number of steps envisioned. Have you tried to do any of them? What error have you encountered? – Vince Nov 10 '21 at 01:29
  • @PolyGeo, yes I do have spatial analyst. I have looked into this, but I could not quite understand where to start. Even the transect tool links provided are not working anymore. – Arthur_Morgan Nov 10 '21 at 01:33
  • I know in ArcMap you can draw perpendicular lines with respect to a polygon, but I don't know how do it in terms of elevation. Another problem is that since the area is very heterogenous. – Arthur_Morgan Nov 10 '21 at 01:42
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    Please use the [edit] button beneath your question to revise it with any requested clarifications. – PolyGeo Nov 10 '21 at 01:44
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    I'm not understanding 'perpendicular transect', can you draw a picture of what your result would ideally look like and edit it into your question. Also are you trying to script this or would an interactive method work for you? – Michael Stimson Nov 10 '21 at 04:32
  • @MichaelStimson, you are right, I have added a rough sketch based on what I understood from this meeting I had. And when I looked at the study area, the elevation is so heterogenous, even I was confused on how to make a 'perpendicular transect ' for this. If my edits still do not make sense, then I will have some clarity tomorrow and edit the question accordingly. Please don't close the question until then – Arthur_Morgan Nov 10 '21 at 05:13
  • @MichaelStimson, an interactive method would work better for me. – Arthur_Morgan Nov 10 '21 at 05:19
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    Would it be reasonable to find the lowest and highest elevation by sorting the attribute table, select both, use feature to point to extract the centroids, draw a line between the two points, with the construct points tool add markers (6-8) along said line then add perpendicular lines, snapping to the points and constrained to perpendicular using Ctrl + E, make the lines as long as you like you can always cut them back later, if you like to be neat you can also constrain with Ctrl + L to limit the length - with both constrained a vertex will be added. Intersecting the perpendicular lines with – Michael Stimson Nov 10 '21 at 06:54
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    your polygons you can pick up the mean elevation for each cell the line passes through which would make it a transect. There is a spatial/3d analyst tool for making a 3d transect if the intersection doesn't meet your requirement which can be viewed in ArcScene and rotated in 3 dimensions to visually asses the transect but I'd want a much finer raster than those cells to get a proper 3d transect. If Ctrl + E/L don't work both perpendicular and limit to length are available by right clicking on the min-max line. Don't panic if your question is closed, any edit puts it in the reopen queue. – Michael Stimson Nov 10 '21 at 06:57

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