I have a polygon layer and a points layer, and I need to extact the top five max points where they intersect. How do I do this?

I have a polygon layer and a points layer, and I need to extact the top five max points where they intersect. How do I do this?

I am calculating the height of each point using LiDAR, and I want to extract the top five maximum heights!

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If you have a sample of the intersect table, it should have a 'key' field identifying the polygon and a Z field identifying the elevation of the intersecting point. If you can save/export/ a portion of the table, I can show you how to do it with python, arcpy and numpy. Conceptually, it just involves grouping your intersecting features on the polygon key field, then sorting by Z and slicing off the top five. The results can be sent back as a table for use in Pro

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Mitchell, it may not be exactly what you want... but it will get you started thinking should you chose to follow the path or take an alternate route

Thank you! I am following the tutorial now, and I am trying to understand your code, but I am having trouble getting arcpy to work with jupyter notebooks. Do you have an example of what the numpy array will look like after arcpy.da.TableToNumPy()?

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I wouldn't use jupyter notebooks.

Spyder.... for coding with Python

would be much better.

A 'structured' array is an array which has named fields/columns. Each field has to contain a unique data type, but a structured array need not contain data of the same type. Think a really smart spreadsheet. Or you will see why Pandas exists because of numpy. So in short, it would look exactly like your table in Pro, except that there are no visible field names at the top.

`array([(1885, 963, 1, 'A1', 300886., 5034392., 12.35, 99),`

(1904, 1036, 1, 'A1', 300575., 5034497., 11.83, 53),

snip.... , ...,

( 519, 572, 80, 'J8', 309695., 5027720., 11.86, 5),

( 275, 49, 90, 'J9', 309371., 5026486., 12.46, 79),

( 295, 1683, 90, 'J9', 309226., 5026555., 11.16, 94)],

dtype=[('OBJECTID', '<i4'), ('FID_pnts', '<i4'), ('FID_poly', '<i4'),

('Grid_codes', '<U6'), ('Xs', '<f8'), ('Ys', '<f8'),

('Norm', '<f8'), ('rand_int', '<i4')])In the above we have field names

('OBJECTID', 'FID_pnts', 'FID_poly', 'Grid_codes', 'Xs', 'Ys', 'Norm', 'rand_int')

and the 'i' s are integers and 'f' s are floats and 'U' is text/string (aka unicode). Don't worry about the number ('i4' is a 32-bit, 4 byte integer, 'f8' 64-bit float, etc)

I can make it look like a 'table' if that would help...

`id OBJECTID FID_pnts FID_poly Grid_codes Xs Ys Norm rand_int`

------------------------------------------------------------------------------------------

000 1885 963 1 A1 300886.00 5034392.00 12.35 99

001 1904 1036 1 A1 300575.00 5034497.00 11.83 53

002 68 594 91 A10 300164.00 5025374.00 12.83 22

003 147 1081 91 A10 300529.00 5025818.00 11.86 24

... snip ....

What do you mean by 'top'? those closest to the upper edge of the polygon?