Questions tagged [samplepoints]
The samplepoints tag has no usage guidance.
14 questions
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How do I eliminate Grid points that are less than a desired distance from my polygon boundary
I'm performing a sampling study using a systematic sampling grid. I have calculated that I need to establish 71 plots that fall within polygons in the area of interest and I have calculated that the ...
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R - Spatial sample from a points layer
I read all day several articles regarding various methodologies and tools to create a significant sample from my initial data but I get lost at some point.
It is a shapefile of points.
I would like to ...
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Using sampleRegions with randomPoints samples less points than what is provided
Link for the code: https://code.earthengine.google.com/89616ca3147334915eca9f3957bb778f
I am using GEE in order to access image, generate random points on top of it and then sample it using the random ...
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gee ranadomPoints fails:Polygon too large to be randomly sampled. Must be smaller than a hemisphere when image is not so huge
I want to sample random points over an image I access using geemap.
I was trying to do it as following:
#access elevation image and clip it with the feature collection
img = ee.Image('USGS/SRTMGL1_003'...
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Get pixel values using rasterio.sample
I would like to get the pixel values for a single point within a .tif file using rasterio. I have read several previous questions, and implemented the suggestions.
Here is the code that I am using:
...
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Sample points randomly on an image using Google Earth Engine
I have an image ('biome') and a feature collection ('grid'). I want to sample points on the image, precisely 10 points per feature(a grid cell). Also, I want to drop points that intersect the masked ...
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Create random points within polygons with certain distance to polygon boundaries using PostGIS [closed]
I am using PostGIS and have a table containing a polygon geometry and a text column containing different factors.
I need to create 5000 sample points, which are located IN the polygons and are at ...
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ee.Image.sampleRegions - what does the geometries parameter do?
I am reading the geemap tutorial and I have question about the sampleRegions function. As I understand, this function "cross" between vector data (feature collection) and a given raster, and ...
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Sample Regions - excludes points with masked bands. Google Earth Engine
I have a set of points from around the world and I want to extract the pixel values from a set of images, giving information about the local environment, for each point. Then export the set of values ...
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Random sampling In Google Earth Engine
I want to select random 90000 pixels/points from region of interest wherever there is built-up area. To my surprise when I print number of pixels selected it shows only 1044. I am literally lost how ...
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Error in random forest regression (Output of image computation is too large (25 bands for 903440 pixels = 106.8 MiB > 80.0 MiB)
I am working with the GEDI dataset and Sentinel-2 spectral indices (about 20-40 bands). My aim is to use the Random Forest Regression to generate a map containing the information on Relative Height (...
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Random sample of points surrounded by similar pixels in Google Earth Engine
I have a single-band raster (US landcover) where each pixel is assigned to one of a few classes. I want to get a random sample of points (lat-long) throughout an area such that each of those points is ...
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Getting properties of random points in Google Earth Engine
I want to have random points across Peru and their properties (the band values of IMAGE) for statistical analysis in GEE. I found two options which are sampling and random points. I have tried the ...
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Error in .bboxCoords(coords) : nrow(coords) > 0 is not TRUE using raster::sampleRandom()
I am trying to sample a raster (pixel values= 1 or NA, where 1 means opportunity as defined for my research).
The specs of my raster are
class : RasterLayer
dimensions : 15838, 3808, 60311104 (...
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