The best approach to assign elevation to points from DTM

Question

Hi all,

I have one points FC with about 5000 points. Their maximum bounding rectangle is 50 by 50 km.

I also have 2500 1m resolution DTM elevation ASC grids. Total size is 17.5 GB OS grid data.

What is the best approach to assign elevation to my points from those grids? Caveat is that while the points cover the 50by50 km area, there are location where there are no points.

I have access to spatial analyst.

Any ideas appreciated.

Anonymous User · Answer

Hi Val:

You could put the grids into a mosaic dataset first, then run one of the extraction tools on that.

However, I think using 2500 input raster datasets should work fine with emv2p or the sample tool. I recommend that you do this from python (build a python array of input grids) instead of trying to run the tool interactively using  2500 map layers.

Let me know how it works.

-Jim TenBrink

spatial analyst team

VaL · Answer

@MehdiPira1

Thanks. I know I can use a few tools from the SA toolbox.

Question regarding the 'tool overload' still remains.

I don't want to run the points against 2500 grids. Hence the question about how to strategy this.

MehdiPira1 · Answer

@VaL ,

you can also use "Add Surface Information" which attributes features with spatial information from a surface like DTM.

https://pro.arcgis.com/en/pro-app/2.8/tool-reference/3d-analyst/add-surface-information.htm