# Questions tagged [interpolation]

The estimation of values at unsampled points based on known values of surrounding points.

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### How do I get accurate DTM from DSM to get tree height?

I have drone imagery which was generated in Agisoft. From the imagery a DEM was generated and exported. I would like to know how do I get the Digital Terrain Model from this DEM? as I currently have ...
1 vote
197 views

### What's the difference between bicubic interpolation and cubic convolution?

Our remote sensing professor recently introduced us to bicubic interpolation and cubic convolution, implying that they're basically the same. Now that I'm studying for the exam, I wonder: Is that ...
2k views

### Interpolating every X distance along line in shapely

If I have a shapely multiline object that contains many lines whose total length each is 50km (when traced from the origin), and I want to interpolate along the multiline every X meters (let's say ...
1 vote
3k views

### Error #010067 when running spline interpolation

I am attempting to run a spline interpolation on a point dataset of 585 features in ArcGIS 9.3, using the spatial analyst toolbar. The dataset holds only latitude, longitude and abundance attribute ...
1 vote
471 views

### Creating prevalence map using QGIS?

I work with infectious disease. Right now i want to create a map showing a prevalence of infected people during an outbreak of the disease. So I have coordinate data of infected/uninfected people ...
22 views

### 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 ...
65 views

### 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 ...
525 views

### Depth map interpolation using QGIS

I've produced an interpolation map using QGIS (a pond) I have 40 points with a vdepthalue, and an additional 33 that represent the edge of the pound (depth 0). My map is as follow: and my TIN ...
2k views

### Using PyKrige for ordinary kriging on an XYZ file

I've previously used ArcGIS for Ordinary Kriging, but I now need a Python alternative. I found the PyKrige module which i decided to give a try, but I am bit confused by it. So far, I have read my XYZ ...
280 views

### IDW interpolation in ModelBuilder by column in ArcMap

I want to interpolate using the IDW method in ArcMap. I have to interpolate the values of several months for several years. I have the data in a shapefile in which each column has the values for each ...
54 views

### TIN interpolation keeps discarding the original values of the sample and interpolates them as well

I'm trying to make a DEM in QGIS using TIN. I have a set of points with elevation data on one of the attributes. My problem is that when I generate the raster, the initial set of point values are lost ...
23 views

### 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 ...
1 vote
58 views

### 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 ...
2k views

### 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, ...
690 views

### Spatial interpolation of climate data using latitude, longitude and elevation in r

I have downloaded E-OBS gridded daily climate data on 0.1-degree grid. For each grid point, I have longitude, latitude, elevation and climate data, i.e. precipitation sum / mean temperature. Now, I ...
291 views

### Interpreting semivariogram from ArcGIS Pro

Am having an output for semivariogram from ArcGIS Pro as per below. However, the distance looks small. Is there a way to adjust the distance? Not only that, how best can I interpret the x and y values ...
64 views

### 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, ...
80 views

### 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?
11 views

### 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 ...
1k views

### Converting River Channel Cross-Section Data to Bathymetry

I have multiple surveyed cross-sections of river channels and need to convert this data into 3D polylines (shapefile) for use in a hydraulic model. The cross-section data is typically supplied in &...
813 views

### Error in gstat.formula.predict(d\$formula, newdata, na.action = na.action, : NROW(locs) != NROW(X): this should not occur

I'm trying to perform regression kriging using the code creating variogram m <- vgm(var(soil\$Ba), "Sph", sqrt(areaSpatialGrid(slope))/4, nugget=0) v <- fit.variogram(variogram(Ba~RASTERVALU, ...
308 views

### Clipping interpolated raster with shape of original point data-set

I have a point dataset with XYZ values. I inserted this layer in QGIS 3.6 via layer > add layer > add delimited layer. Then, I interpolated these points to a raster via interpolation > TIN ...
39 views

### 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-...
271 views

### What is the latest and stable QGIS version support SAGA with Multilevel B-Spline interpolation

I am trying to interpolate elevation points to create a digital elevation model (DEM) on QGIS (v3.22.13). One previous research suggests that Multilevel B-Spline interpolation (MBI) in SAGA is the ...
169 views

### Spatio-temporal Kriging and how extract specific values

I have several years of data that needs to be converted to STDFDF. Shapiro.test and Adf.test talk about non-stationarity and non-normal distribution. particolato_May2021 <- read.delim(file = "...
760 views

### Kriging method vs. IDW in soil moisture interpolation

I have XY coordinates and soil moisture values for a grid of 10m and I used add XY data to import my excel data to ArcMap 10.5. I applied both IDW and kriging methods for interpolation. The results ...
31 views

### 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 ...
1 vote
48 views

478 views

### QGIS Smart Map Plugin - Error Running Interpolation

I am new to using the Smart-Map plugin. I added my data and did the ordinary Kriging interpolation. Just before it reaches 100% I get the following error message: An error has occurred while executing ...
29 views

### 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 ...
586 views

### Why does no interpolated line appear when I use the 3D Analyst to generate a elevation profile in ArcMap?

I want to generate an elevation profile based on a DTM with ArcMap 3D Analyst but the program does not show the the interpolated line. I did the following steps: Opening 3D Analyst, adding a Digital ...
50 views

### 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 ...
162 views

### NoData fill QGIS (alternative to nibble tool in ArcGIS)

I have two raster layers - one is a mastergrid, the other shows slope. I want to 'expand' my slope raster so that it covers the same extent as the mastergrid by in some way interpolating the 'missing' ...
21k views

### Performing Kriging in QGIS

Does anyone know how to perform kriging in QGIS? and not via SAGA but actually in the program itself.
397 views

### QGIS TIN interpolation - error in pixel size of output

When using the "TIN Interpolation" tool in QGIS 3.10, the output raster file doesn't keep the pixel size I specify. For example if I specify a pixel size of 1.0m, the output file actually has a pixel ...
1k views

### R kriging raster returns NA for some prediction points?

I am trying to interpolate a raster layer of chlorophyll-a data using kriging (gstat::krige) in R, however the resulting interpolation is showing NA values in a peculiar straight line through the ...
5k views

### Breaklines in QGIS interpolation plugin

How can I prepare data to generate a DTM using points and breaklines, but where every breakline has nodes at different heights. For example, a river valley, which regularly falls, or a dorsal line, ...
20 views

### 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 ...
108 views

### 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 ...
2k views

### z-Coordinate and interpolation plugin in QGis [closed]

I've a csv file that includes weather stations locations (x,y,z) and precipitation values. I loaded the file by using add delimited text and then converted it into a point shapefile WS84. By using the ...
4k views

### 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 .....
42 views

### 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). ...
1 vote
44 views

### 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 ...
1 vote
53 views

### 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\...
75 views

### 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 ...
1 vote
90 views

### 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 ...
300 views

### GRASS GIS v.surf.idw not working correctly

I have recently been struggling with an issue in GRASS. I am a new GRASS user and recently downloaded version 7.8.5 for my MacBook (macOS Catalina). I converted this sample dataset to a shapefile. I ...
4k views

### Interpolating in ArcMap [closed]

I am trying to make a raster from point data. My data is in .txt form and contains of x,y,z; that is, coordinates and elevation. I have about 156000 points. So, these points are imported into ArcMap, ...