I have a "grid" (vector grid) of evenly spaced points for ocean alkalinity. At every location in the grid there is a stack of up to 15 points with identical coordinates but different values for their depth and alkalinity attributes. I need to join the alkalinity values for the deepest points at each location to another point layer.

How can I create a selection that will grab just the deepest points at each location?

This is not a simple get max value from the entire layer problem, I need the points with the max depth value at each of 6000 point stacks.

I've tried various versions of this: "depth" = (SELECT MAX("depth") FROM INPUT) in the select by attribute window but get a bunch of syntax errors. I'm pretty sure I also need some other selection attribute like a unique coordinate ID so I'm picking the max from each stack and not just the whole data set. I have that ID created.

Any help is greatly appreciated!

David

How can I create a selection that will grab just the deepest points at each location?

This is not a simple get max value from the entire layer problem, I need the points with the max depth value at each of 6000 point stacks.

I've tried various versions of this: "depth" = (SELECT MAX("depth") FROM INPUT) in the select by attribute window but get a bunch of syntax errors. I'm pretty sure I also need some other selection attribute like a unique coordinate ID so I'm picking the max from each stack and not just the whole data set. I have that ID created.

Any help is greatly appreciated!

David

I think that will work. I already have the unique ID for each stack (concatenated X and Y coordinates) so that as the Case Field in the summary statistics tool should give me what I need to join back to the data to get the max points. I'll try it with the student I'm helping when we meet next week and will report back if this was the solution.

Thanks!