Extracting all XY coordinates from within a polygon?

Question

I have multiple polygon shapes covering the UK. How can I create an Excel spreadsheet of all 6 (sometimes 7) figure XY British National Grid coordiantes that fall within these polygons? I don't want just the XYs of the polygon verticies, but all coordinates intersecting the polygon.

DarrenWiens2 · Answer

Have you considered using (or spatially enabling) your database do a point-in-polygon comparison, rather than pre-populating every possible point? Alternatively, calling a geometry service to do the comparison for you? for example: Geoprocessing - Point in polygon search | ArcGIS API for JavaScript 3.22

curtvprice · Answer

However this would result in a 1TB+ raster (I don't have that space anywhere!).

Integer rasters are stored compressed, and in this case the values are repeated (polygon id repeated for each cell inside a polygon) so the raster will be much smaller than rows x columns x 4 bytes (32 bits).

If you are really planning to make a row for each grid-point in an Excel spreadsheet, you may want to consider every 100m (10,000x less rows) or 50m 2,500x less rows) and using a table lookup. If some of your polygons are too small to have one point in them, you you can use the MAXIMUM_AREA option in your polygon to raster operation to make sure small polys aren't "dropped" in your raster.

TheodoreF · Answer

My colleague wants to upload it to our online database to replace our current post code dataset. So when a client places an order (including post code and XY) we can match it to our list of XYs instead of our postcodes (which are less accurate spatially).

And good point about the issue of having millions of records re: Excel!