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

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31
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 ...
14
votes
4answers
16k 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 ...
7
votes
1answer
917 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. ...
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 ...
3
votes
3answers
685 views

Using National Agriculture Statistics Service (NASS) county level crop data to estimate crop acreage in hydrologic regions?

National Agriculture Statistics Service (NASS) provides county level crop (Corn, Soybean, Sorghum, etc) data. I want to calculate crop acres on each subwatershed from the county based data. I'm ...
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. ...
8
votes
6answers
945 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 ...
16
votes
2answers
2k 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 ...
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 ...
3
votes
1answer
188 views

Debugging errors of SAGA interpolation algorithms in QGIS 2.0 Processing

I encounter recurrent problems with the geoalgorithms that perform interpolations. No matter technique I use I end with the following errors. As state in OGR tab QGIS is unable to open a file in C ...
6
votes
3answers
805 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
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 ...
12
votes
2answers
587 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
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 ...
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" ...
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 ...
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 ...
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 = ...
7
votes
5answers
2k views

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 ...
7
votes
2answers
294 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 ...
6
votes
1answer
383 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
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 ...
3
votes
1answer
286 views

Area precipitation using IDW

I'm having the following problem with IDW automation. I have a catchment and several gauging stations measuring daily precipitation amounts. I would like to interpolate the precipitation amounts from ...
2
votes
0answers
207 views

how to make decent sense from scattered river depth measurements

I sampled river depth at scattered positions and I want to be able to make a map and GIS layers out of it. My problems are: As the river meanders the interpolation I do in scientific packages i,e. ...
2
votes
1answer
1k views

interpolation methods in qgis

I have a points layer and I want to create an interpolation grid with QGIS 2.0. If I use Raster -> Analysis -> Interpolation the extent of the output raster is good (rectangular shape) but it ...
0
votes
0answers
74 views

Issues creating slope raster layer from a point layer

I'm trying to create a slope raster layer using QGIS 2.0 on Windows XP. I started with a points layer with the Z elevation attribute. I then used the interpolation plugin to create a DEM. But, ...
5
votes
1answer
416 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 ...
4
votes
1answer
462 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
4answers
783 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 ...
3
votes
1answer
286 views

How to exclude stations from IDW interpolation?

I have the following problem: I need to calculate an average precipitation amount on a catchment using an IDW interpolation. The interpolation is performed in a loop since each precipitation station ...
2
votes
2answers
1k views

Are there only two methods of interpolation in QGIS?

I did recently a map of maximum temperature for specific area in Quantum GIS 1.8.0 and its interpolation. However, I was wondering if there are only two method of interpolation, apart from ...
2
votes
1answer
2k views

TIN Interpolation using a vector layer

I'm writing a plugin in QGIS and I'd like to generate a TIN surface using a vector layer with x,y and z (interpolation attribute). The idea is to visualize the same result like in the Interpolation ...
1
vote
0answers
30 views

How to calculate average wind speed at a particular location (given longitude and latitude)? [on hold]

I am using ArcGIS 10.2 and new to this software. My question iss I have time series wind speed data in netCDF form. I extract netCDF in raster form after that in table form. Now I need How to ...
1
vote
2answers
54 views

Interpolation with z-values taken from a related table

This is a follow-up question (organizing attribute table: multiple sets of variables per point). I am working with ArcGIS 10.1, advanced license. My aim was to build a points layer, each point being ...
1
vote
3answers
241 views

Which interpolation method for noise mapping?

I want to create a noise map with measured point data. But i want to have a planar representation, so I need an interpolation method. Which one is the 'best' one for measured noise data? I prefer to ...
1
vote
1answer
236 views

Restricting Tin interpolation in QGIS

I am trying to do a bathymetric map for a lake using QGIS. However, I see no option to impose a mask so interpolation does not extending beyond the boundaries of my lake. I have traced around the ...
1
vote
0answers
386 views

Source code for interpolation using a known set of random points in an area of land

In a fixed area of land random points with their values are generated. I need to get a heat map for this area of land showing the variations using those known point values. I have found that mostly ...
1
vote
1answer
473 views

How to use buffers to estimate the attribute data for a given polygon?

I have two layers: point and a polygon. The point layer has lat/long and I have created buffers of a 1/4 mile. The polygon layer has data such as age and income. Is there a plug-in that can ...
1
vote
2answers
3k views

How to create distinct polygon zones from interpolated raster in ArcGIS

I would like to create smooth/distinct polygon zones from raster data that was interpolated from sparse point data. Is the only way to do this is to have a very small output cell size during the ...
1
vote
2answers
373 views

ArcGIS API Interpolation Functions

Does ArcGIS API provide interpolation functions, like if I want to interpolate from my own set of values? Edit: I know that ArcGIS provides functions for interpolation like IDW, Spline and Kriging ...
0
votes
0answers
43 views

Displaying Interpolated surface [duplicate]

Possible Duplicate: Displaying/Accessing interpolated data I successfully carried out IDW interpolation procedure on rainfall data, using the spatial extent, same pixel size, and same pixel ...