Questions tagged [interpolation]
The estimation of values at unsampled points based on known values of surrounding points.
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Deciding what interpolation method to use for resampling raster data?
Are there hard and fast rules about which interpolation methods are suited to each kind of raster data?
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Open source methods for kriging?
I have a point dataset which I'd like to Krige, ideally using an open-source software package. If possible, I'd also like to choose the semi-variogram model during the process to improve the ...
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Choosing IDW vs Kriging Interpolation for DEM creation?
I'm trying to create a DEM using point data spaced very regularly about 10m apart. The area I am interpolating is an educational facility with many flat parking lots and football fields but still has ...
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What resampling technique should be used when projecting aerial photos?
I'm doing some time-intensive projecting of aerial photos.
What resampling technique is best to use on aerial photos?
In ArcMap, my options are NEAREST, BILINEAR, CUBIC, and MAJORITY.
Nearest Neighbor ...
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Smoothing/interpolating raster in Python using GDAL?
I am developing in Python and using GDAL from OSGEO to manipulate and interact with rasters and shapefiles.
I want to take a shapefile that has point features and interpolate it into a surface raster....
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Minimum number of samples for kriging interpolation
I get some data with number of specimens with a request to interpolate it using kriging method.
After some investigation it appeared that kriging results (performed in ArcGIS Geostatistical Analyst ...
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Which interpolation technique is suitable for a bathymetry of a small lake?
This is a lake of approximately 13 ha with 81 sampled depth points in about 10 transect lines:
Previously in ARCgis with a 50 ha lake and about a 100 depth sampling points, I got decent output with ...
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Looking for interpolation tool to produce river bathymetry (topography) from sections
As per the title, I am looking for a tool that can produce bathymetry of a river from cross sections. Although people who may know such tools probably will not need any explanation why this kind of ...
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Modelling of rent prices - which interpolation method to use?
I have national dataset of ~1,4 million households. There I have information about rent, size (number of rooms and m2) and some additional characteristics of each household.
I'd like to use this data ...
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How to interpolate GPS Positions in PostGIS
I have a PostGIS table of GPS positions for every five seconds:
2011-01-01 00:00:05, POINT(x1,y1)
2011-01-01 00:00:10, POINT(x2,y2)
2011-01-01 00:00:15, POINT(x3,y3)
...
I'm looking for a query that ...
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Bilinear interpolation of point data on a raster in Python?
I have a raster that I'd like to do some point interpolations with. Here is where I'm at:
from osgeo import gdal
from numpy import array
# Read raster
source = gdal.Open('my_raster.tif')
nx, ny = ...
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How do you use GRASS's v.kernel?
I am flummoxed on how to use GRASS's v.kernel.
I have a vector layer of around 2.5 million points. I want to make a heat map using v.kernel to show concentrations, since I have variable instances with ...
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Spatio-temporal interpolation in R or ArcGIS?
I'm trying to calculate average rainfall value from a number of points using Inverse Weighted Distance tool in ArcGIS 9.3.
My problem is that: each point has it own time series, therefore the ...
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Picking coefficient in Inverse Distance Weighted method of QGIS?
I'm using QGIS 1.8.0 to interpolate weather data. This is, I have a weather station located in say, A and C. With the Inverted Distance Weighting or Triangular Interpolation methods, I can know/...
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Performing Spline interpolation on GPS Track
I'm looking for a way to apply spline interpolation to a gps track (GPX format). I am a regular QGIS user and also have GDAL libraries installed on my Mac if that helps.
Basically trail and ride ...
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Should point data be equidistant projected when using ArcGIS IDW spatial interpolation?
I am wondering if anyone can clarify whether point data should be projected to an equidistant projection when using ArcGIS IDW spatial interpolation?
I am working on a dataset from Western North ...
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PostGIS interpolation / triangulation options
I'm looking for an open source workflow to automate DEM construction. We have a series of sites that fall within a LIDAR dataset. We want to create site specific DEM's for each site, and we're ...
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How to interpolate temperature correctly?
I tried to interpolate the mean average annual temperature to produce a "realistic" surface. In QGIS I used Raster-Interpolation-Interpolation. Both methods TIN and IDW did not deliver a "realistic" ...
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R gstat krige() - Covariance matrix singular at location [5.88,47.4,0]: skipping
When I want to perform the kriging it only works sometimes, depending on what values I use in my datatable. As a result of the krige function I get for var1.pred: NA NA NA ... and var1.var: NA NA NA .....
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What is the best technique for interpolating soil depth from sample points
This is my first post here.
I have some points from a soil depth survey and I need to interpolate the depth for a whole area. What is the most appropriate technique for this and is there anything I ...
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Shortest Path using interpolated OSM points
I have a set of GPS points which I have snapped to the OSM network. In the below screenshot GPS points are red, snapped points are green.
I want to calculate the shortest path that includes all of ...
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Interpreting semivariogram with high nugget effect?
I made a semivariogram in R using package gstat, variogram() function. I want to see if there is spatial autocorrelation in the residuals of my model (species abundance as a function of habitat, ...
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How to grid unevenly sampled categorical data?
I am looking for a method for gridding categorical data. I have extracted from nautical charts and field sheets a collection of points specifying the nature of the surface of the bottom of the ocean. ...
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Kriging with barriers in ArcGIS Desktop?
I am trying to do interpolation in a coastal area with data points in several rivers emptying into a bay and on opposite sides of peninsulas.
I have created a coastline layer to use it as a barrier ...
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Accurately interpolating elevation from contour lines in QGIS?
I’m trying to interpolate elevations from contour lines (~70000 at 1m intervals, spanning ~20km^2) in QGIS.
When I interpolate using Inverse Distance Weighting (IDW) in the Interpolation plugin it ...
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Interpolate data from multiple gpx tracks
I have a number of GPX tracks of the same road. But due to GPS error they are not accurate enough (20-30m off).
I'm wondering if I could interpolate those multiple gpx tracks into single one. If an ...
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Spatio-temporal block kriging with R package gstat?
In the documentation of sp I saw that the coords argument of the SpatialPolygons function only accepts 2 columns. Is it not possible to create 3-dimensional polygons? I am doing spatio-temporal ...
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Interpolating degree data using QGIS?
I want to create wind maps. There is an introduction for ArcGIS and for QGIS. As I don't have access to the Spatial Analyst, I gave the QGIS-version a try. However, I don't know how to interpolate ...
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Replica of point layer data from attribute value in QGIS
I am working in QGIS 3.2 and am wondering how I can create an "exploded" version of a single layer of point data based on numerical attribute values within that layer.
As a simple example, ...
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Plotting map resulted from kriging in R
I want to plot a map weighted by prices. I got a data frame of latitudes, longitudes and prices:
> str(data)
'data.frame': 1253 obs. of 3 variables:
$ lon : num 11.2 11.1 11 11 11.3 ...
$ ...
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PostGIS: Interpolate/Cluster geographic points to average points
Setup: PostGIS 3.1, QGIS 3.16
I have a bunch of geographical data (geometries). They show more or less the same route, just measured several times. Due to the many measurements and the GPS precision, ...
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Interpolate smoothly nodata values in QGIS
I have a DEM raster where all the buildings have been extruded and now contain "nodata" values. I'd like fill the holes and get a nice and continuous surface (which would approximately correspond to ...
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How to choose raster interpolation method?
I work with a dataset of ~1.3 million residential buildings; each of them is described by a normally distributed variable ranging from 0 to 100. The dataset covers whole Switzerland so there are ...
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Interpolation of multibeam bathymetry using ArcGIS Desktop?
I'm trying to make a 3D map with multi-beam bathymetry (65536 features, xyz), but it seems that the interpolation methods are too rigid. I need to smooth the data so it looks more natural and ...
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Partially updating raster (DEM)?
How to update an .img DEM in ArcView 9.3?
I do have DEM which need to be updated only if few parts. The area to be updated has been produced in separate DEM with Spline Interpolation with Barriers.
...
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Interpolating Maps - Statistical Learning Techniques vs Spatial Statistics Techniques
I have recently begun experimenting with the interpolation of variables over a whole country.
I have good sized training set where I have several dependent variables (continuous and categorical) ...
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Filling NA gaps in raster with R?
I have soil data rasters from SoilGrids.org that have some small holes with NA cells (White spaces in the image) that I want to fill using some interpolation method to get a more spatially continuous ...
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How to interpolate a lat/long point between two others at a given distance
I'm trying to solve the problem of interpolating a point at a given distance (in meters) between two other lat/long points. (e.g. P1 (50,10), P2(50.01, 9.990), I want to interploate P3 at a distance "...
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Hex grid value interpolation in POSTGIS
I have a table of tessellated hexagons that I created as a hex binning grid to cover an area.
I've then overlaid a point set to give some of the hexagons a value, see diagram:-
The shapes with value ...
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Interpolating points observed with different time duration
I am doing spatial interpolation with a group of points.
Some points have complete observation of events:
for a period of 24 hours we have observed N events in each point. These points have N events....
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How does Empirical Bayesian Kriging of ArcGIS Pro handle sampling bias?
In ArcGIS Pro, simple kriging approaches allow you to de-cluster your data before applying a normal-score transformation. According to the Esri guideline, normal-score transformations are only ...
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Estimation of values for unsampled points
I want to measure biomass on a coastal mudflat. I can only access points inside the polygon. Are there any methods available that would allow me to estimate values of the points outside of the polygon,...
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Weather data interpolation? [closed]
I'm trying to carry out weather conditions interpolations. I have information of 92 weather stations for 800,000 km2. As you can imagine the extension of land is huge and I need some kind or weather ...
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Strange spatial interpolation results from ordinary kriging
I'm using Ordinary Kriging to interpolate a set of spatial data. I'm working on different sets which represent different days of measurement. I get good results, apart from one specific set. Will post ...
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How to calculate kriging weights?
In Esri's documentation on how to make a prediction in Kriging, I couldn't figure out the linkage between the semivariograms and the prediction process from reading the description therein:
After ...
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Performing Kriging in QGIS
Does anyone know how to perform kriging in QGIS? and not via SAGA but actually in the program itself.
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How to Create Contours for Zonation
I'm still new in the world of GIS.
I'm currently doing some zonation with "test points." Each has its own coordinates and "P" value. I want to make contours of these data, to divide the whole area ...
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What type of interpolation to visualize metal detection survey data?
I have about 500,000 points collected in a linear grid pattern over a 1 km2 area. The points were collected as part of a metal detection survey. Each point has X,Y and Coil Response mV (min -675.38 ...
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Converting points to raster in ArcGIS?
How do I create such map from point data?
I am using ArcGIS 9.3 and 10
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Kriging with barriers in R?
I wonder if there is a way to interpolate xyz points in a raster within certain bounds using R? In ArcGIS this is called interpolation with barriers. I wonder if there is something similar in R? I ...
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