民族宗教理论甘肃研究基地专家委员在北京座谈
百度 三款车当中，只有宋MAX的发动机拥有直喷技术，而它的扭矩也是最高的，同时最大扭矩输出的起步转速却是最低的。
Measuring data values at specific, discrete locations.
123 questions
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How to obtain a CSV file (feature collection) from a very large image in Google Earth Engine
I have a particularly large image (encompasses a large area at high resolution with 30 bands). I would like to have a CSV file with one pixel per 10km grid cell, and another CSV file with one pixel ...
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44
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Cluster sampling of line data
I would like to create clusters of line data (geometry) for sampling, the geometry would be connected within each cluster. So far I’ve thought of:
Create a bounding polygon > split it into X ...
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2
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78
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EarthEngine: how to sample pixels returning pixel geometry, not points
I would like to sample pixels within a given region, and extract the sampled pixel as a polygon. This will be used for ground-truthing at the polygon level.
I thought Image.sample would be the perfect ...
- 2,112
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1
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138
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Using Point Sampling Tool of QGIS
I am trying to sample raster values at locations in a points layer, using the Point Sampling Tool - a process that I have done successfully in the past. The process is failing with a Python error:
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- 489
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233
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How to auto-update field on geometryChanged() signal?
I have a point XY layer with a Z field used only for annotations. Sometimes there is a need to update the the geometry by moving the point manually. Since the layer is stored on an mssql server, the X ...
- 361
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130
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Extracting values over a large area in Google Earth Engine: memory optimisation
I am trying to sample satellite (Sentinel-2 spectral metrics) data over a rather large area (1500 by 2500 km). I have around 2000 points relatively evenly distributed over this area.
However, even ...
- 61
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69
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Spatial clustering vs sampling
I have a dataset with 100 millions Point (lat/lon).
I have started by using GeoHash clustering (applied dynamically by Elasticsearch regarding the user zoom level).
I end up with something like that:
...
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2k
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Stratified random sampling in R
I want to generate 5 pairs of random points per each stratum. I have 4 strata that represent different rock types. For each rock type i want to generate 5 random points and to each random point I want ...
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272
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Smart Map plugin: error sampling 5000 data points
I'm trying to use the Smart-Map plugin in QGIS to do Kriging. I have about 15,300 data points and I need to sample the data (5,000 points, maximum for Smart-Map right now). But this error appears when ...
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1
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134
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Failed to print projection in GEE after sampleRegions
I'm using the function sampleRegions to extract the iamgecollection values from the sample plot I imported. I assigned the projection at first when doing the sampleRegions , however, when I want to ...
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37
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Estimating resolution interpolated from point samples
I have a series of data samples (actually satellite measurements), and I am interpolating the data to produce a raster. I can interpolate to any arbitrary resolution I like; but how can I estimate the ...
- 1,324
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180
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Avoid adding a bunch of new features for one static location for repeat sampling efforts in Field Maps
I have built several maps and forms for their use in Field Maps for various projects. Most have been creating new features and filling out the form for the new location where we sampled. However, we ...
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1
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204
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Selecting points based on random index location from a filtered GeoDataframe in Python?
I have a large point vector file (and many others like it), where each point has a integer value in the column "DN". However, I only need 6 points per DN and want them to be selected ...
- 231
1
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2
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144
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Randomly select non adjacent polygons in vector layer (QGIS) [closed]
I am trying to obtain a random selection of polygons (e.g., 100 polygons out of 400) with the condition that the selected polygons are not adjacent among each other.
Any suggestion on how to achieve ...
- 131
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1k
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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 ...
