Thank you very much Michael. My idea is to create a spatial nested grid to conduct spatial surveys for a monitoring protocol.
I am thinking to create an 8km, 4km, 2km and 1km nested grids so you can use different tiles according to the desired resolution of species occurrences, landscape metrics, or other metrics. See this https://gis.stackexchange.com/questions/386664/creating-nested-grid-in-qgis Manuel El vie, 10 feb 2023 a las 16:38, Michael Sumner (<mdsum...@gmail.com>) escribió: > One way is to write it to a (COG) GeoTIFF with overviews ("pyramid", or > zoom levels) - these are pre-calculated copies of the highest resolution > data saved as lower resolution versions. > > Do you want this to generate a set of nested data, or is it more about > working with the nested logic? > > I'm not sure what version of GDAL is required to write one directly with > terra or raster, but i'll explore. In terms of the nesting logic , you can > read a particular zoom level (or model it with an data-empty object) and > determine cell index using the cells tools in terra (or raster). I think > you would need to generate xyFromCell and use that to cellFromXY between > layers (the arithmetic is not onerous but doesn't exist for reuse anywhere > in R afaik). > > I'm interested in this generally for workflows I'm using so might come > back with an example, happy to follow up related questions. > > At the command line with COG format you can do > gdalinfo in.tif overviews.if -of COG -co OVERVIEW_COUNT=3 ## 3, for > example > > or > > gdal_translate in.tif overviews.tif > gdaladdo overviews.tif 2 4 8 > > but, of course there are implications with tile pattern and potential > overlap for a given size. You'd probably also want tiling enabled and > choose a particular tile size (perhaps to match the next resolution down). > And I'd definitely want to make sure my extent was clean whole numbers and > choose sensible sized zoom and tile levels. > > Cheers, Mike > > > On Fri, Feb 10, 2023 at 10:22 AM Manuel Spínola <mspinol...@gmail.com> > wrote: > >> Dear list members, >> >> Is it possible to generate a spatial nested grid in R? >> >> For example, a grid of several 8km x 8km tiles, and within that grid, I >> want 4 tiles of 4km x 4km, and in each of those I want 4 tiles of 2km x >> 2km, and in each of those I want 4 tiles of 1km x 1km. >> >> Manuel >> >> -- >> *Manuel Spínola, Ph.D.* >> Instituto Internacional en Conservación y Manejo de Vida Silvestre >> Universidad Nacional >> Apartado 1350-3000 >> Heredia >> COSTA RICA >> mspin...@una.cr <mspin...@una.ac.cr> >> mspinol...@gmail.com >> Teléfono: (506) 8706 - 4662 >> Institutional website: ICOMVIS >> <http://www.icomvis.una.ac.cr/index.php/manuel> >> Blog sobre Ciencia de Datos: >> https://mspinola-ciencia-de-datos.netlify.app >> >> [[alternative HTML version deleted]] >> >> _______________________________________________ >> R-sig-Geo mailing list >> R-sig-Geo@r-project.org >> https://stat.ethz.ch/mailman/listinfo/r-sig-geo >> > > > -- > Michael Sumner > Software and Database Engineer > Australian Antarctic Division > Hobart, Australia > e-mail: mdsum...@gmail.com > -- *Manuel Spínola, Ph.D.* Instituto Internacional en Conservación y Manejo de Vida Silvestre Universidad Nacional Apartado 1350-3000 Heredia COSTA RICA mspin...@una.cr <mspin...@una.ac.cr> mspinol...@gmail.com Teléfono: (506) 8706 - 4662 Institutional website: ICOMVIS <http://www.icomvis.una.ac.cr/index.php/manuel> Blog sobre Ciencia de Datos: https://mspinola-ciencia-de-datos.netlify.app [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
