Questions tagged [large-datasets]
difficult to process and manage because the size is usually bigger than the limits software can normally deal with.
122
questions
1
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0answers
16 views
How to build raster file from large folder tiles (256x256), which has 70.000 file tiles
First, I'd like to mention that I'm new to working with GIS, so please forgive my inexperience.
I have map folder with structure: zoom level contains multi tile image files (256x256),ex: folder zoom ...
0
votes
1answer
68 views
How to handle layer that contains millions of vertices in QGIS
I have a multi polygon layer with 25 features, each containing millions of vertices, holes, etc. It is a statewide floodplain. Right now, it takes forever to draw even when zoomed in, plus the ...
1
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0answers
9 views
What is a good way to store a large (tiled) geo raster?
I have a large geotiff raster map (after compression 88 GB) as a series of 919 geotiff-tiles. How can I turn these into a practical file solution (e.g. one file) that allows me to efficiently work ...
2
votes
1answer
37 views
Creating random points using ArcMap
I want to create 100 random datasets in ArcMap for a particular area. Each dataset should contain 10,000 random points. I am using the "Create Random Points" tool in ArcMap.
Can anyone ...
-1
votes
1answer
29 views
Calculate NDVI in a large feature [closed]
I'm having some trouble with my GEE script. I have to calculate NDVI of each feature of my shapefile, but it is too large. Someone could help me with this code? I think it's king of simple, but I'm ...
1
vote
2answers
54 views
Count how many new points are captured when a polygon buffers by x miles
I have a polygon and a layer of many points. How many more points would be captured if I expanded the polygon by x meters? I want to end up with values for x = 1 mile, 5 miles, 10 miles, and maybe a ...
3
votes
1answer
115 views
Using PostGIS to find the overall difference between two (large) polygon datasets
I need to get the Difference of an input layer with ~30k polygons and an overlay layer with ~500k polygons (of which ~200k intersect the input layer).
I am trying to learn PostGIS to do this, as it ...
2
votes
0answers
70 views
PostGIS: Using ST_CoveredBy (or similar) to speed up Difference on large datasets?
I need to get the Difference of a single large-area polygon (input layer) and a very numerous set of polygons (overlay layer). The overlay layer has ~500k polygons, of which ~200k intersect the input ...
0
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0answers
82 views
Google Earth Engine large reduce resolution and reproject fails to export to drive
I'm attempting to aggregate (reduceResolution) a higher resolution image (e.g. 30m global forest loss as in code below) to a lower resolution image (e.g. 1000m pixels), based on some criteria, with a ...
1
vote
1answer
55 views
What is the canonical way to perform raster calculations using R stars?
I have a data cube that I am handling in the R stars package. It has 3 dimensions (latitude, longitude and time) and 2 attributes (northwards and eastwards components of wind). A dummy equivalent ...
1
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0answers
27 views
GEE large export of pixels using shapefile polygons: Is it possible to automate a division of the polygons asset?
I need to export pixels from a processed image of Sentinel-2 using GEE Javascript with a 10 pixel size. The export is for pixels within 120,000 land parcel polygons.
I am way above the limit for pixel ...
0
votes
1answer
72 views
Leaflet - remove data from layer?
I have a quite complex webapp with a lot of data on a map. Except the basemap, the data of each layers are coming from AJAX queries, witch's responses are formatted as GeoJSON object -- up to this ...
0
votes
0answers
25 views
How to calculate and store (ArcMap) slope on huge mosaic dataset?
I have a huge raster dataset stored in a geoDB (DHM with 2m resolution for all of Switzerland), uncompressed size ~75 GB. I want to use the ArcMap Slope tool (or another tool would also work) to ...
0
votes
1answer
78 views
How to normalize a large point cloud using lasheight and a .tif DTM?
I am normalizing a large point cloud (>16 GB), for which I'm using a preprocessed DTM that I store as .tif.
For smaller amounts of data, I would use an R script that lets me do this:
library(lidR)
...
0
votes
0answers
244 views
Export large area data in Google Earth Engine
I am trying to average an image collection from 2019-02-01" to "2019-02-28 on Earth Engine platform. My goal is to export the data in Google Drive that I can use it in QGIS for other ...
2
votes
1answer
94 views
Intersecting large shapefiles onto a grid in QGIS
I have 21 separate shapefiles containing data for Ireland as various
polygons on QGIS 3.10. I'm trying to intersect each shapefile onto a
250m² grid of Ireland so that I'll have 21 separate shapefiles ...
0
votes
0answers
147 views
Calculate and plot the feature importance of the input dataset of a random forest classification within Google Earth Engine
I run a random forest classification for agricultural land use and other land cover classes (12 classes). My dataset for 2019 consists of a Sentinel 1 and Sentinel 2 monthly time series, statistical ...
2
votes
2answers
108 views
Zonal statistics USFS tree cover by census block
I want average tree cover for every census block. I have a file of census blocks, and I have a USFS tree cover file from USFS Tree Canopy Cover Datasets that looks like this:
I'm trying to use zonal ...
1
vote
2answers
127 views
gdal_calc raster calculation fails on 28 GB GeoTiff
I am trying to do a raster calculations on a 28 GB GeoTiff using gdal_calc.py (3.0.4) but the process fails
gdal_calc.py -A DEM_0.tif --outfile=DEM_1.tif --calc="A+0.33" --format=GTiff --...
0
votes
1answer
79 views
Large-scale cloud masking, grouping and mosaic in Descartes Labs platform
I am looking to create a stack of cloud-free sentinel-2 imagery by day for a large portion of California for all of 2020 in the Descartes Lab platform. I realize that this is a very large amount of ...
1
vote
1answer
438 views
Google Earth Engine: Error exporting a large Feature Collection to CSV
On GEE, I want to export daily weather variables for 18 years for about 30,000 rectangular polygons. That would be exporting a FeatureCollection to a csv file with ~200 million rows (30000 places * ...
1
vote
0answers
142 views
Generate synthetic trajectory dataset that has global coverage
I want to generate a spatial trajectory dataset which basically contains tuples - (lat,lon,time), grouped together by an identifier so they form trajectories. In addition, I want this dataset to have ...
0
votes
0answers
60 views
Georeferencing larger GeoTIFF's in QGIS
I have a GeoTiff (>100GB) and I want to georeference it in QGIS using the georeferencer option. I did manage to create the GCP's (>15) but when the georeferencing is set to run, it crashed mid-way. ...
4
votes
1answer
477 views
Calculating max shardSize and fileDimensions to avoid tiling large raster exports in Earth Engine
I am exporting a very large raster in Google Earth Engine to my Google Drive. I am trying to keep my exported raster to 1 file to avoid additional processing to merge the tiles (e.g. GDAL merge in ...
-1
votes
1answer
542 views
Exporting large rasters in Google Earth Engine
When exporting large raster data in Google Earth Engine to your Google Drive, is there a function that prevents the export from automatically tiling into smaller files, or even decreases the number of ...
3
votes
2answers
535 views
Publishing a large and complex map to the web
I have created a complex map of my area and I wish to publish it as an interactive map on the web. The dataset appears to be too large for QGIS2Web to work - the script completes eventually but in ...
1
vote
2answers
160 views
Heatmap of a large polyline dataset in QGIS
To summarize: I'm having difficulties with creating a heatmap from a large (90021-item) polyline dataset in QGIS 3.10.1.
First, it is worth noting that this question is somewhat similar to Doing ...
3
votes
1answer
78 views
Merging and snapping shapefiles
I have several large shapefiles from various sources. All cover various sections of oceans and many overlaps, as such the coastline is repeated across the several shapefiles but to varying levels of ...
0
votes
1answer
228 views
Serving large (1.7Tb) dataset of aerial images with GeoServer
I have a large dataset of aerial images consisting of 8000 TIFFs where single images are no larger than 0.5G and all have have .ovr pyramid files with them.
Previously I have served this dataset as ...
4
votes
4answers
1k views
Convert large OSM files to GeoJSON
I have been trying to convert a large OSM file (5G) to the GeoJSON format. All the tools I have been using, use extensive memory and throw an out of memory exception.
What is the best way to convert ...
1
vote
0answers
51 views
Leaflet: Load GeoJSON point data in polygon, when selecting polygon
I've got a point dataset (~ 160.000 points) which has a filesize of around 30 MB. Because that is too large I decided to slit it into 12 separate GeoJSON files. I've got a map with 12 polygons. When ...
0
votes
1answer
26 views
Creating a layer with selected values (divided by commas) from another layer - query or model needed
I have a very large dataset in ArcMap 10.6 and I would like to create a subset that selects only rows that have specific attributes (some of them with special characters) from a field that in my case ...
1
vote
0answers
80 views
Extracting or masking of very large raster to reduce file size on disk?
I have a very large 8-band raster (339806 x 61704) that I cannot load to memory to manipulate (R, raster:canProcessInMemory indicates I need 4999.16 GB of ram to load this file). However, I only need ...
0
votes
1answer
64 views
Counting points contained in polygon for large number of points in ArcMap?
I'm trying to determine the number of points within a set of polygons for a large number of points. There are 2GB of lat-long coordinates in a CSV file, and I want to see how many are contained in ...
0
votes
1answer
216 views
Reduce processing time for large GeoTIFF image
I am trying to process large GeoTIFF images (128 MB) using GeoTIFF reader provided by Geotools library. However the processing time is very high, can anyone suggest how to reduce this time.
Normal ...
1
vote
1answer
67 views
Why does geodataframe never complete?
I had a feature class made up of 1,700,000 polygons. I used Geopandas to create a geodataframe:
state = "MD"
state_gdb = r"C:\Projects\Pop_Alloc\{}_Data.gdb".format(state)
join_feat = "{}...
1
vote
0answers
95 views
R process: Zonal Stat Raster has No Data Values vs Arc output
I am trying to re-create my ArcGIS Zonal Stat model with R
All my files will be 30m pixels; 18000 x 18000.
I have used R two different ways to create the output and both create NoData values in the ...
0
votes
0answers
28 views
Union very large layer in FGDB and only keep one polygon that is overlapping?
I'm trying to union an exceptionally large layer (45k features) of footprints with many of them largely overlapping. I'd like to union this layer but I'm having trouble due to the size of it. The end ...
2
votes
1answer
890 views
How to snap to a geojson-vt layer (Vector Tile Layer)?
I'm using geojson-vt to render a large geojson (originated from OSM) file. This file contains all road from a state (extracted with overpass-turbo way[highway="*"]). I'm buinding a domain-specific ...
3
votes
2answers
205 views
Script I made for pyQgis runs slow but can't find another way around it
registry = QgsProject.instance()
first_layer = registry.mapLayersByName('buffered')[0]
second_layer = registry.mapLayersByName('buffered')[0]
areas = []
instrument_number = "tin_ttl_in"
proprietor =...
0
votes
0answers
78 views
ArcMap fails to convert all records from CSV file using Table to Table geoprocessing tool
I am using the table to table geoprocessing tool to convert a CSV file with nearly 5 million records into an GDB table in a file geodatabase. The tool succeeds each time, but only 603 records are ...
1
vote
1answer
1k views
Saving raster to BigTIFF in QGIS?
Using QGIS 3.4, I am trying to merge multiple DEMs downloaded from the National Map Viewer that are in ArcGRID format (Arc/Info Binary Grid). The output will be a large file so I can't use any of the ...
7
votes
3answers
6k views
Converting large GeoJSON to shapefile?
I have recently downloaded a building footprint GeoJSON file from Microsoft Bing Maps. The file I downloaded was for the entirety of Texas, and is of approximately 2.2 GB file size. They do not ...
1
vote
1answer
145 views
Using “Difference” geoprocessing tool on Big Data taking a very long time
I am using QGIS Bonn 3.2.3.
I've recently been using the Difference function to calculate a list of points and it is taking a terribly long time. I was wondering if you could point out any obvious ...
1
vote
0answers
375 views
GeoServer GetMap with geopackage very slow (with high zoom levels)
I have a GeoServer instance and have imported multiple high res tiff files as layers and created a layergroup from the layers. When I call the WMS endpoint with a specified bbox and the geopackage ...
0
votes
0answers
138 views
Improving performance of Eliminate tool in ArcGIS Pro?
My data is very large (polygon feature class with 884187 features), thats why Python geoprocessing tools (which use geoprocesses like Intersect, Buffer etc.) don't work due to performance issues.
So ...
0
votes
0answers
356 views
Merging multiple rasters (Very large dataset)
I am working on project to create a DSM raster for whole Kentucky. I will have over 46000 tiff tiles and each one is about 10 Mb and one band. Normally, I use Mosaic to New Raster Tool but this time ...
3
votes
2answers
1k views
Calculating time efficient seasonal means from raster bricks?
I'm starting from a Rasterbrick like that called r.brick:
class : RasterBrick
dimensions : 17, 19, 323, 21915 (nrow, ncol, ncell, nlayers)
resolution : 0.11, 0.11 (x, y)
extent : 8....
1
vote
1answer
88 views
Are there any continental-scale flow accumulation products besides Hydrosheds?
I am trying to compute branching angles of drainage networks for roughly the western half of the U.S. Because many of these streams are non-perennial (don't have water all year), some of the standard ...
0
votes
1answer
1k views
Extract values from large rasterstack, R
I have a large rasterstack of about 500 objects. I want to sample easch object with the use of a SpatialPointDataframe and then export the results as file.csv. I have tried the following but within ...
