Create an equal area grid over a buffer of points

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Create an equal area grid over a buffer of points

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Last edited Oct 9, 2012

Created on Oct 9, 2012

This example visualizes a rectangular grid of points covering a 50-kilometer buffer around input locations, with each point representing the centroid of a grid cell in an equal-area projection. The SQL query first buffers the original NAD83 geometries, then unions and reprojects them into the Lambert equal-area projection (SRID 97314) to create an envelope, and finally generates a 1000-by-1000-meter grid using CartoDB’s `CDB_RectangleGrid` function. Each cell’s centroid is reprojected back to WGS84 (SRID 4326) for display, ensuring spatially uniform sampling across the buffered area.

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