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I have created a point layer with ~150 points. I have a DEM beneath it, which is where I have taken the X and Y values from.

Does anybody know how I can retrieve the Z values, without using the info button?

I am using ArcGIS Desktop 10. I have licences for the spatial analyst etc tools.

  • Extract Values to Points or Zonal Statistics. Sometimes Extract Values to Points does not work correctly with large numbers of points. – Barbarossa May 28 '14 at 17:31
  • I have tried this. It is telling me that I have an invalid output extent. Can I check with you that this sounds right? input raster or feature zone data - The points; Zone field - POINT_Z; Input value raster - The DEM; Output raster- location+name of where it will be saved; Statistic type - mean. Thanks very much – Katie C May 28 '14 at 17:41
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    Are your DEM and point data in the same projection? That can sometimes lead to the error you mention. – JWallace May 28 '14 at 17:51
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From what I can tell Ryan Garnett's answer is the correct one. If I could attach an image to a comment I wouldn't be posting my own "answer" but it should look like this:

Extract Values to Points Tool

This tool creates a new Shapefile (file folder location) or Feature Class (GDB) with a field attached that has cell values for Z-axis (or whatever attribute value the raster represents).

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You will want to use Toolbox --> Spatial Analyst --> Extraction --> Extract Values to Points

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  • I've tried to do this, but it only gives me x and y. Do I need to change something under environment? I couldn't figure it out. – Katie C May 28 '14 at 17:30
  • I have never had an issue with this process. An alternative is to use GME (Geospatial Modeling Environment) spatialecology.com/gme and use the isectpntrst tool – Ryan Garnett May 28 '14 at 17:56
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I would use either Extract Values to Points or Zonal Statistics as Table (same as zonal statistic, but with a table output). However, the former tends to not collect values for all points if there is a large number of points.

Using Zonal Statistic as Table I would do the following:

First, add a field to your point feature class, call it ID, and use field calculator to copy the OBJECTID (or FID) values into the ID field. The reason being that you need a unique value for the zonal statistic ZONE field.

Then with Zonal Statistic

  • input raster or feature zone data -> point feature class (or shapefile)
  • zone field -> the ID field mentioned above
  • input value raster -> the DEM
  • Output table -> \path\to\outputtable
  • statistic type -> min or max (doesn't matter since there will be only 1 value)

Finally, join the output table to your feature class based on ID field.

  • So, I have managed to get x,z,y coordinates into the attribute table. I had not stated that I would have z coordinates when I first created the feature class. However, the z coordinates are all 0. Do you know how to fix this? – Katie C May 28 '14 at 18:06
  • I have tried your zonal statistics but it returns the error 'output table: <empty>'. Sorry about the late reply, I have been away for a while. – Katie C Jun 8 '14 at 9:38
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You need the the 3d Analyst tool license to get z values. open arc scene, enable the 3d analyst(the 3 analyst tool bar becomes activated and you can see it on your screen), click the small button directed downward at the edge of the tool bar(customize), click the commands tab, drag the feature to 3d tab and include it in the tool bar, click on it, another dialog opens up, click the point shape file you want to have z values for, select your raster file, go to spatial analyist tool bar in tool box > Data managment > features > Add X&Y coordinates

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