Need to extract specific XYZ coordinates from a dataset

**pdog** · 08-31-2012, 08:30 PM

Each of these records are geographic coordinates. Each point has its own unique X,Y, and Z values. There should not be any duplicate values. I need to extract the record with the highest Z value AND the highest X value. I also need the record with the lowest Z value AND the highest X value. Any ideas?

**martindwilson** · 08-31-2012, 08:43 PM

what takes priority?there are no pairs that are the max of both x and z for example

**pdog** · 09-01-2012, 01:23 PM

There is no priority. Max function does not help with this problem as far as I can tell. I think a search array function with logical conditions is necessary but idk the code for that.

**shg** · 09-01-2012, 01:27 PM

Sort by columns A and C descending. The topmost row has the largest x value, and the largest z value having that x value.

I expect that's not what you want, though, so you need to do some more 'splainin'.

**pdog** · 09-02-2012, 01:37 PM

Sorting does not give me the highest Z and X value... The coordinates are a LiDAR point cloud cluster for a powerline tower. For each tower in an alignment I should logically be able to select the point that is the highest (Z) and the farthest (+X) away from the ground or base of the tower.

**mikerickson** · 09-02-2012, 02:52 PM

Please define "highest Z and X value"

Given this data set, what row is the "highest Z and X value"

0, 1, 1
1, 1, 0
1, 0, -1
2, 1, -1
-1, 3, 2

the point that is the highest (Z) and the farthest (+X) away

One problem is that the highest Z might not be the furthest X. How would you compare two X,Z pairs to determine which is highest/furthest?

Possibly, what you could do is add a helper column with =SUMSQ(A2,C2) and sort on that column.