jiayuasu opened a new pull request, #3261: URL: https://github.com/apache/sedona/pull/3261
## Did you read the Contributor Guide? - Yes, I have read the [Contributor Rules](https://sedona.apache.org/latest/community/rule/) and [Contributor Development Guide](https://sedona.apache.org/latest/community/develop/) ## Is this PR related to a ticket? - No: this is a documentation update. The PR name follows the format `[DOCS] my subject` ## What changes were proposed in this PR? Add a blog post about the raster Python UDFs shipped in Sedona 1.9.1: "Seven Lines of NumPy, 121 Million Pixels". The post walks through computing NDVI over a Sentinel-2 scene of California's Central Valley end to end: reading the red and NIR band COGs from the public `sentinel-cogs` bucket with the tiled `raster` reader (512 px tiles), pairing the bands with a join on tile position, computing NDVI in a two-raster Python UDF that returns a raster via `with_bands()`, and writing the result back as Cloud Optimized GeoTIFFs with `RS_AsCOG` and the raster writer. It also covers using rasterio/SciPy inside UDFs, NODATA handling, the same-grid boundary, and how the workload distributes. Cross-links the tiled reader, STAC, and raster metadata posts. Includes a cover image (five real NDVI output tiles from the run plus the UDF code) and a before/after figure, both generated from the actual outputs. ## How was this patch tested? - Every code snippet in the post was executed against the released artifacts: a fresh venv with `pip install apache-sedona==1.9.1` and `sedona-spark-shaded-3.5_2.12:1.9.1` / `geotools-wrapper:1.9.1-33.5` / `hadoop-aws:3.3.4` from Maven Central, reading `s3a://sentinel-cogs` anonymously. - All numbers in the post (484 tiles per band, 76 s end-to-end, NDVI ranges) are the measured output of those runs; the written tiles were read back with the `raster` reader and checked with `RS_BandNoDataValue` / `RS_SummaryStatsAll`, and verified to be internally tiled with overviews and deflate compression. - Both images are rendered from the run's real outputs. - `pre-commit` passes, including the manual-stage `oxipng` hook on both PNGs (idempotent on second run). - Verified the rendered page with `mkdocs serve`: images resolve, code highlighting works, and the blog star-CTA hook is appended. ## Did this PR include necessary documentation updates? - Yes, I have updated the documentation. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
