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

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30
votes
9answers
10k views

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 ...
15
votes
2answers
1k views

What resampling technique should be used when projecting aerial photos?

I'm doing some time-intensive projecting of aerial photos, and I'm curious - what resampling technique is best to use on aerial photos? In ArcMap, my options are NEAREST, BILINEAR, CUBIC, and ...
14
votes
4answers
15k views

How do you decide what interpolation method to use for resampling raster data?

The question pretty much says it all; are there hard and fast rules about which interpolation methods are suited to each kind of raster data? Any Golden rules, rules of thumb? Good books or articles ...
13
votes
2answers
2k views

How to smooth/interpolate a raster in python using GDAL?

This is my first post so please feel free to critique where necessary. Background: I am developing in Python and using GDAL from OSGEO to manipulate and interact with rasters and shapefiles. ...
12
votes
6answers
2k views

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 ...
12
votes
1answer
1k views

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 ...
12
votes
2answers
569 views

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 ...
11
votes
3answers
515 views

Modelling of rent prices - which interpolation method should I choose?

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 ...
11
votes
1answer
2k views

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 ...
10
votes
5answers
689 views

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 ...
10
votes
3answers
1k views

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 ...
10
votes
2answers
1k views

Interpolation for timeseries in 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 ...
9
votes
4answers
5k views

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 = ...
9
votes
4answers
2k views

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 ...
8
votes
6answers
922 views

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 ...
7
votes
4answers
2k views

How to interpolate temperature correctly?

I tried to interpolate the mean avyerage annual temperature to produce a "realistic" surface.In qgis I used Raster-Interpolation-Interpolation. Both methods TIN and IDW did not deliver a "realistic" ...
7
votes
1answer
1k views

When to use 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 ...
7
votes
2answers
2k views

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 ...
7
votes
5answers
1k views

What type of interpolation should I use 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 ...
7
votes
2answers
281 views

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 ...
7
votes
1answer
903 views

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. ...
7
votes
2answers
225 views

How to handle interpolation of multiple (quality) tiers of irregular data?

I'm going to try to provide a high level overview of the issue - realizing that more details/info will be necessary - but I don't want to write a novel that seems too overwhelming for people to ...
7
votes
1answer
447 views

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. ...
6
votes
2answers
1k views

Creating geodatabase from CSV using python

I have a file with weather data (daily) for multiple weather stations for multiple years. I am looking for some python script to automate the database creation process and its interpolation on a daily ...
6
votes
4answers
792 views

Interpolation of Three Data Points

I have three location point: weather points. It's a 10-year composite of temperature values which means I only have three values for three locations for ten years. I want to interpolate these points ...
6
votes
3answers
134 views

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 ...
6
votes
1answer
1k views

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 ...
6
votes
6answers
522 views

Interpolation of multibeam bathymetry

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 ...
6
votes
2answers
5k views

Correct way to create a DEM from point data in csv files

I know this might seem a somewhat general question, but I have to start somewhere. I have a lot of csv files which contain point data containing height, aspect and slope measurements at a resolution ...
6
votes
1answer
367 views

ModelBuilder: How to extract data by date, export to separate tables and interpolate tables to rasters

I've been using ArcGIS for a couple years, but when it comes to model builder I've only worked with very simple models. I'm hoping someone that is much smarter than myself can help me in building a ...
6
votes
1answer
179 views

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 ...
5
votes
2answers
407 views

Optimum grid/pixel size for interpolating rainfall and temperature

I have a set monthly rainfall and temperature data within an approximately 100 x 100 km study area. The sampling points are unevenly distributed within the study area. Based on a paper by Janis et. ...
5
votes
1answer
500 views

Change the image size in ARCGIS

I did interpolation operation on temperature and precipitation data. Output image size is 3300 (col) and 2550 (row). I have some NDVI images with size of 15456 (col) and 5074 (row). Generally, I want ...
5
votes
2answers
1k views

How to interpolate while providing clipping geometry? (ArcGIS 10)

Is there a way to interpolate (IDW) while providing clipping geometry? My objective is that I want to interpolate temperature data but I do not want it to interpolate the entire extent of the point ...
5
votes
3answers
2k views

How to interpolate into polygons?

I need to interpolate values from points to polygons. I have a point shapefile and a shapefile of adjacent polygons. Some polygons get several points falling inside, some have nothing. I thought ...
5
votes
2answers
436 views

Spatial Analysis with Factors/Classifications

When doing analysis on spatial data with associated information that is numeric, it is possible to use techniques such as Kriging or Interpolation or Cluster Analysis to find out interesting ...
5
votes
1answer
400 views

How to interpolate polyline or line from points?

We have a lot of points, but with no timestamps to create ways. For now, I've created a sample of the way the points traverse. It's in here, this way can be compared with a Google one. I haven't ...
5
votes
2answers
113 views

PostGIS - Interpolate point between contours

Using PostGIS, what is the best method to interpolate the z value for points (the orange dot in the image below) located between each contour layer (blue lines and red lines in the image below)? So ...
5
votes
2answers
678 views

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 ...
5
votes
1answer
742 views

Are special interpolation techniques required for weather data?

I've downloaded a series of weather observations from the local weather agency - it comprises around 1,000 points spread non-uniformly across Australia, with a greater density of points located near ...
5
votes
3answers
158 views

What are the most efficient Geographic Weighted Regression packages?

What are the most memory efficient open source packages for calculating a geographically weighted regression (GWR)? I am in a situation where I need to do a geographically weighted regression on a ...
4
votes
1answer
447 views

Interpolation of Values in ArcGIS

I wanted to interpolate the trend values (trend of sunshine hour calculated over 20 years) throughout the study area from the available station points. My confusion is in the selection of ...
4
votes
2answers
600 views

ArcGIS, Calibrating routes, interpolation error

I know that copy a question is not exactly great way to ask on this forum, but my situation is exactly the same as this unresolved issue on the (closed) ESRI forum: I have a stream centreline ...
4
votes
2answers
197 views

Which kriging method is the best for the rainfall?

I am working on an rainfall analysis and I have to interpolate some datas with kriging method. So is co-kriging the best one for the rainfall analysis?
4
votes
1answer
784 views

Interpolating Maps - Statistical Learning Techniques vs Spatial Statistics Techniques

I have recently begun experimenting with the interpolation of variales over a whole country. I have good sized training set where I have several dependant variables (continuous and categorical) ...
4
votes
4answers
757 views

TIN interpolation crash in Qgis

I have problems using the function TIN(linear) interpolation in Qgis. The program crashes when larger areas is interpolated. Map properties: vector map, Geometry typ = Point, features in this ...
4
votes
2answers
1k views

Point interpolation in route

I have a set of GPS coords with X,Y and Course. I need to interpolate additional points based on the course of each point. It would be a simple line intersection based on lines drawn using the 2 ...
4
votes
1answer
150 views

Interpolating vertically in 3D analyst

Here is my problem: I am working on mapping pollutant concentrations in a pond from point-sampled data. There are 50 sampling locations in the pond (randomly dispersed), and at each location there ...
4
votes
1answer
99 views

How to add points to LAS copy using liblas?

I am trying to make a copy of a LAS file while inserting new points using python liblas module. The code below creates the copy and adds the points, but for some reason the added points are not in ...
4
votes
1answer
309 views

Is it possible to do spatial interpolation using points in a field?

I would like to use Quantum instead of ArcGIS to make field map but before, I need to know if its possible to do spatial interpolation with definited points in a field (ex. pH points). Is there a ...