Questions tagged [interpolation]
The estimation of values at unsampled points based on known values of surrounding points.
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Fill NA cells accross rasters
I have a raster stack (spatraster) with 129 layers. The layers are monthly images from Landsat-8. A lot of cells contain NA values due to clouds. My goal is to fill these NA pixels with some sort of ...
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3D interpolation visualization with ArcGIS Pro
I would like to use the result of a global polynomial interpolation as a base for visualizing a 3D model in the local scene view in ArcGIS Pro, but I always get back a flat layer in the local scene ...
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ArcGIS JS API RasterShaderReliefRenderer does not color full range of DEM elevation values
I have a DEM of the state of florida as an ImageService, here. I want to render this DEM using nicer colors than black and white using the ArcGIS JS API. Following the example ImageryTileLayer - ...
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Groundwater interpolation using kriging with external drift
I have a bunch of groundwater measurements that I would like to interpolate taking into account the ground elevation. For this, I was advised to use kriging with external drift. I have tried different ...
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DCELL cell type is set automatically for raster after r.resamp.interp
After interpolation with r.resamp.interp with bilinear method DCELL cell type is set for raster. When I export it with r.out.gdal I get a precision loss error, as I export it as Float32 (PCRaster ...
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Finding interpolated value from raster data in PostGIS
I have a series of values that were computed for each cell on a grid on a given territory.
Those values has been stored in a raster field in PostGIS (there are no missing data).
I want to run a query ...
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gdal_fillnodata strange artifacts
I'm seeing an odd artifact when using gdal_fillnodata.py.
I have a raster
(purple is no data, white and black are two different numeric values).
Using a mask exactly corresponding to the no data ...
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LineString length obtained from shapely differs from actual real distance [duplicate]
I want to obtain the points of a LineString that are at a distance of 25m from the first point and from the last one of said LineString. I was doing some tests to check whether or not Shapely could be ...
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Create heatmap polygons shapefile from a points shapefile for a variable in attribute table in R
The objective is to create heatmap polygons from a points shapefile named "df_sf" for an attribute "V1" in the shapefile and then export these polygons as another shapefile in R.
...
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How to show point data as a colored map?
Im doing one, I would say, simple analysis, but Im rookie when it comes to GIS, so I need help. So, I have data of CPT (cone penetration test) which our firm conducted over the years and within that ...
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Problem with SAGA batch processing
I have a series of point clouds in LAZ format that contain points identified as ground. I want to interpolate these points with the Multilevel B-Spline algorithm of Saga GIS and export the clouds to ...
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TIN interpolation QGIS - Voronoi Polygons
I'm trying to interpolate 12 points in QGIS linear within a Voronoi Polygon using TIN-Interpolation created for the points. However,the extent of the raster layer only interpolates between the points ...
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How to use Lagrange interpolation method for station lies between a grid?
I have rainfall data for a catchment from 1990-2020 in grid format. But my station of interests lies in the grid, how to apply the interpolation to that station. I'm not sure if I'm proceeding ...
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How to divide a geographic area into N latitude and longitude quadrants
I would like to get the NW1,NW2,...NWn and SE1,SE2,...,SEn lat and long coordinates of N quadrants starting from an area identified by 2 geographic points: NW and SE.
I would like to write a Python ...
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Re-projecting an orthographic image to a equirectangular projection has some sort of problem. The poles are getting truncated. missing parameter?
Re-projecting an orthographic image to a equirectangular projection has some sort of problem.
The poles are getting truncated. is there a parameter I am missing?
Is there a difference between "...
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Interpolating flood surface using Topo to Raster in ArcPy
I am trying to interpolate a statewide flood surface for NJ using Topo to Raster in ArcPy. I split the input points into 900 separate input point feature classes using 14-digit watershed boundaries. I ...
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Can't open IDW interpolation while I'm using QGIS 3.34
I can't open IDW and TIN interpolation. How can I solve the problem?
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Add missing values to raster data set [expand, not fill holes] in QGIS
I'm relatively new to QGIS and have run into the following problem.
I am using a raster soil data set that was cut to the country border. However, since the cut was rough and my research area is set ...
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Working on a manual NTv2 bilinear interpolation
I asked this on the Math Exchange, but I figured I'd also post it in here to see if I could get some insight from some GIS folks. I think it is a math problem, but maybe my process is wrong. Any ...
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Problem interpolating point shapefile QGIS
I've been having a lot of problems trying to interpolate some topographic point data from the coast of Japan. The data consist on regular separated points 10 meter apart. I've tried to interpolate ...
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Python: interpolate dataset to create a global map
I have a NetCDF dataset (this) with values for the world's oceans. The measurements are in the form of unevenly spaced points:
Now I want to extract some values at specific locations. My problem is, ...
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Interpolate a GeoJSON file [closed]
I have a GeoJSON file which consists of rainfall data in a location.
I want to interpolate those point data in GeoJSON and make a raster file, and display in Leaflet map. How can I do this?
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QNeat3 Polygons do not finish calculating interpolation
I have been using QGIS for a couple of years and used QNEAT3 for the first time around one year ago. I never had any problem with it but, after some months not using it, I tried to use it again to ...
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Creating Raster from CSV in QGIS - Huge filesize
I am attempting to create a magnetic map of Northern Ireland using this dataset (https://www.opendatani.gov.uk/@geological-survey-of-northern-ireland/gsni-tellus-regional-airborne-geophysical-survey-...
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vis.gam spatial interaction output as a raster grid instead of plot object
I am trying to create an object that can be put into tmap or another GIS platform from my model output. I created a model using the gamm4 package that has a spatial interaction term. See an example ...
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Minimum datapoints for Kriging
Are the datapoints (34) for this Kriging operation sufficient?
Research Gate recommends > 30. [both -> here and here], while another source [-> here] mentions 30 to 50. All mention Webster ...
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Unable to get the road network distance between two points in PostGIS
SELECT
sf.id,
sf2.gid,
SUM(ST_Distance(
sfroads.geom,
ST_LineInterpolatePoint(sfroads.geom_latest1,
ST_LineLocatePoint(sfroads.geom_latest1, sf....
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73
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Create conical gradient around a point using R
I have a point on a map that I am simulating bird movements from. I'd like to create a raster grid around this point with a conical gradient, similar to the picture below.
The idea is that the birds ...
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Coordinate-based interpolation of values in time series format
I have three different streamflow gauge station points along a river. For each point, I have streamflow values as timeseries. Between these station points (Red triangles on the map) I have additional ...
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Using data for interpolation in Geostatistical Wizard of ArcGIS Pro
i do have soil temperature data (5 cm depth) from 1991 and 2021 for Germany, and wanted to interpolate the data for each year as a class of 3 seasonal months (winter = 12, 1, 2; summer = 6, 7, 8). ...
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Improving kriging results from transect data
I have estimates of fish density along transects from a lake and would like to extrapolate these estimates for the entire lake surface, using kriging methods. Based on information from here, here and ...
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ArcPy IDW interpolation with LiDAR point cloud data
There are several questions such as 1, 2 etc on interpolation, but, when I implement the same procedure to calculate digital terrain model from point cloud I get an error:
las_path = r"C:\Users\...
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Switch begin and endpoint in profile graph - ArcGIS Pro
I created a profile graph in ArcGIS Pro. The TIF file that I use to create the profile, via the function "Interpolate Shape", contains the elevation in Europe.
The line that I created starts ...
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Convert a pixel-aligned grid to node-aligned [closed]
Given a regular grid of squares with sample points at their centres (a pixel-aligned grid), what would be the best way to interpolate to the corners of the squares (a node-aligned grid). I'm aware of ...
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Find and select local maxima on a raster
I'm trying in ArcGIS to obtain local maxima from a raster (for example a DEM) calculated with a circular sliding window of constant radius. Is there a way to pick up and select the local maximum ...
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Bilinear interpolation of a matrix to extract Z at different locations [R]
I have that geoid heights (quasi-geoid model hBG18) in a form that matrix :
library(tidyverse)
Geo <- read.table("https://www.isgeoid.polimi.it/Geoid/Europe/Belgium/public/hBG18.dat",
...
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Resample() function in R's terra package and the r.resamp.interp module in GRASS GIS yield such different rasters
Comparing the results from the resample() function in R's terra package (version 1.7-29), and the r.resamp.interp GRASS GIS module (version 8.2), I find differences in how they apply bilinear ...
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RMSE in interpolation
I am doing interpolation for a chemical concentration in loamy soil across a very large arable land. I used simple kriging, IDW and EBK. The data distribution was skewed so I had RMSE of close 100 for ...
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Spatial Interpolation of Point Layer with Count and Associated P-Value
Here's quick synopsis of the data I have. I have a dataset of just under 100 points with most points being coincident with several other points resulting in roughly 15 unique locations. Each point ...
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How to make interpolation and contour for recording distances on images?
I have a question about interpolation and contours.
In the images from the animal observation cameras, we would estimate the distance from the camera to the animal. In theory, we had the idea of ...
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1
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Extracting points in a regular interval from TIN-Interpolation raster in QGIS
I had million of points with x, y and z. I could not filter them in QGIS in order to get them in an interval of every 0,9m. So what I did is TIN-Interpolation and I do have a raster now.
How can I get ...
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85
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SAGA Close Gaps - using the mask parameter?
I'm trying to interpolate cells in a gap in a raster layer using SAGA's Close Gaps tool. It works fine when I don't use the mask parameter, but when I do, it fails to generate the layer. There's not ...
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Error with pycnophy R function from predicts library
I am attempting to use the pycnophy() function from the rspatial/predicts library. Upon prepping county level data with a "population" metric and running these data through the function, I ...
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Interpolate underwater quality data with QGIS as with Surfer with Kriging method [closed]
I'm trying to interpolate conductivity data form a coastal area about 4-6 square km from a series of 10-20 probe wells more or less equally distributed.
I have access to a licensed Surfer and to QGIS ...
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QNEAT3 Iso-Area as Contours interpolation problem
I have a network of roads in district, and i want to make Iso-Area as Contours from Layer of points (schools). So, I have some problems with it. Firstly, I don't understand why these jagged contours ...
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Expand a given bathymetry / DEM through interpolation towards 0 depth at coastline polygon
I have a grid of a bathymetry of a fjord (grayscale in the image below). The grid doesn't reach all the way to the coastline (blue polygon) because it originates from sonar surveys where shallow ...
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Point Interpolation in ArcGIS
I have a set of data points in a CSV format. I want to create a contour map using the data points so I used IDW Interpolation in ArcGIS. But, when I checked the maximum value of the output raster, it ...
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Interpolating missing pixels from land cover classification map
On Google Earth Engine, I created a classified land cover map based on a composite of images (spanning 2 years). It's a time series study so increasing the range of images (i.e. increasing to more ...
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TIN Interpolation in QGIS but with a predefined Delaunay triangulation
I have a set of points from which I am trying to perform a TIN triangulation.
However, the algorithm for the triangulation (i.e. the resulting raster) creates triangles that I would like avoid for the ...
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450
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SAGA GIS - regression kriging
I have a problem with regression kriging in SAGA under QGIS. It gives me an error - could not execute the tool. I want to create temperature maps from data set of meteorologic station and DEM.
I have ...