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

learn more… | top users | synonyms

1
vote
1answer
91 views

Smoothly interpolating Polygons from set of coordinates?

I'm still quite new to QGIS and I'm using it to display and analyze my soil data. I have point information on the distribution of the soils in a specific area and I need to create a soil map from ...
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 ...
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 ...
0
votes
0answers
18 views

How to minimize output raster errors using topo to raster tool

TLDR:Is there a way to specify an angle of rotation for an interpolation output based on the angle of input lines? In our line of work, we often create straight line contours that represent a sloping ...
1
vote
1answer
49 views

Extracting raster values with polylines in QGIS

I have a polyline shapefile that represent a road an a raster grid with slope values. Is it possible to interpolate the shape file and the grid to have the average slope of the road? I know that I can ...
0
votes
0answers
16 views

What are the advantages of interpolation vs raster from point elevations?

I want to make a potentiometric surface map. I have a bunch of wells plotted. The way I learned would be to make a raster of elevation of ground surface and another of depth to water and perform ...
5
votes
1answer
853 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) ...
2
votes
1answer
48 views

Calculate Height Data From Three Known Points

What's the best way to calculate "height" (snowfall, actually) data from three surrounding locations? For this example, I'm looking to arrive at a "close enough" snowfall value at point A by ...
0
votes
1answer
116 views

Difference spatial interpolation and trend surface analysis

What is the difference between spatial interpolation and trend surface analysis? For example, I read a scientific study that applied a neural network to estimate a surface solely based on the x and y ...
3
votes
1answer
244 views

Can ArcGIS handle missing values to create a contour map?

I am trying to create a contour map for a waterbody. It turns out that in several locations there is no data. I just don't want to use the missing values as zero in ArcGIS because it would create ...
4
votes
2answers
137 views

Spatial interpolation - appropriate method to estimate the accuracy of the surface

When using a spatial interpolation method (any method) without having a way to validate it, besides sampling some points out, is there a way to count as well with the mean distance between ...
3
votes
1answer
253 views

GIS beginner - interpolating contour lines from TIN-model vs. Grid in ArcGIS

I am a complete beginner in GIS and taking a class right now, and we are doing some assignments in ArcGIS - ArcMap. In one of them we were given a shapefile with heightpoints. These had been manually ...
5
votes
1answer
102 views

How to determine the optimal raster resolution when interpolating a surface from points?

I'm looking for guidance on how to determine the desired output resolution, when interpolating a surface from irregularly-spaced point samples. I have a series of boreholes taken across a city, and ...
1
vote
0answers
22 views

Optimized interpolation method with fixed-location sample data points?

I'm trying to find an optimized spatial interpolation method that deals with fixed-location sample data points. Say if I have fixed-location sampling sites and collect data daily, and then use these ...
2
votes
0answers
41 views

How to Interpolate very large datasets in QGIS?

I am working with a very large set of point data, (XYAttribute) which I wish to display as a raster. I've been using Interpolate, this is successful but very slow. I have other programmes that ...
1
vote
1answer
67 views

Workflow of Processing Landsat data for landcover classification

I have downloaded Landsat-8 data to make a land-use raster. So far I've made a composite image and clipped it by my study area. As you can see, there is some slight cloud cover. I've gone ahead and ...
2
votes
1answer
303 views

Postgis 1.4 - Obtain closest point of point over polylines layer (without st_ClosestPoint)

I´ve got a polylines layer (pipes) and a points layer (valves) and In Postgis 1.4 I would like to obtain the closest points but exactly on the closest polyline. In other words, i need to locate each ...
3
votes
0answers
34 views

Elevation interpolation along a (sewer) line

Here's what I want to do. I have a vector sewer line feature class that contaings a field for the high invert elevation and one for the low invert elevation. I can turn them into a raster no problem ...
2
votes
1answer
118 views

How to Interpolate through ModelBuilder?

I would like to create an iterated interpolation tool through ModelBuilder. I have an excel file containing different columns and each column represents a data that will be interpolated using Spline ...
3
votes
2answers
101 views

Interpolation on set of points in QGIS

Is it possible to perform Interpolation in QGIS with input as a vector layer which has a set of points collected following a specified path?
5
votes
3answers
175 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
0answers
41 views

Interpolating species data from sample points in a small area

I have sample data from a small site (10 acres) which shows the number of occurrences of a particular species of snail over two sampling periods (fall and spring sampling). I want to try and ...
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 ...
3
votes
2answers
74 views

Open Source Interpolation Service?

We are seeking an open source solution for dynamic (on the fly) IDW or Kriging points interpolation. Basically we are looking for something similar to ArcGIS Spatial Analysis Service. ...
3
votes
0answers
24 views

3D distance and topography

I have a set of points and want to find out the nearest distance to a water body (poly lines) taking into account the terrain and get a surface distance calculation. I understand that the way is to ...
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 ...
4
votes
2answers
42 views

Repeating steps based on different field using ModelBuilder?

I have built a model to interpolate air pollution from 40 recording stations using IDW. The results are then exported to an average for census divisions. I need to repeat this process hundreds ...
0
votes
0answers
21 views

Interpolating points to surface not working

I am trying to create a surface from points using IDW interpolation. Have tried both 3D analyst and Spatial Analyst tool with my selected xyz data sheet. It appears to process and I don't get an error ...
1
vote
1answer
43 views

Is there a way of applying an exact Kriging interpolation?

Can Kriging be an exact method? For example, when optimized with the Geostatistical wizard? Or in any other way? (as far as I know, "normal" Kriging isn’t an exact method).
0
votes
1answer
34 views

Parameters for optimizing interpolation in ArcGIS for Desktop?

Is there any criteria to know the most proper parameters for an interpolation method in ArcGIS (such as, for IDW: Neighbors (min and max), sector type, semiaxis length, angle, search neighborhood)? ...
1
vote
1answer
45 views

Predicting in advance which is the best interpolation method for my data

I need to interpolate in ArcGIS 10.1 soil data (organic matter content, nutrient content, pH, etc.) from a set of soil sampling points to the surface which this set of points lays on. I am ...
5
votes
2answers
126 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 ...
6
votes
3answers
143 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 ...
3
votes
1answer
69 views

Underwater terrain modeling

My task is to model the surface of a lake bed, calculate volume of it and visualize it as 3D a surface. I have acquired depth measurements in a small lake using echosounder. The precision should be ...
2
votes
0answers
60 views

best method for gridding or interpolating elevation data

I wonder if someone can recommend the best method for gridding elevation data in QGIS, GRASS or similar. The elevation data I have is collected along 1m spaced lines at approximately 1 reading per ...
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 ...
3
votes
3answers
161 views

Fast and robust open source portable script or tool for interpolation - triangulation or similar

I am looking for some fast and robust open source interpolation library/script/tool. The goal is to re-interpolate relatively big (1M+ points) unstructured (xyz) grids into high resolution cartesian ...
0
votes
1answer
20 views

How to convert 3d profiles to points in ArcGIS 10.1

I have created some 3d profiles using the Interpolate Line button (in ArcGIS 10.1). Which looks like: I would like to convert these lines into points and in order to do that I am under the ...
1
vote
1answer
42 views

Interpolation outside the contour of a set of points

I have a field contour in a shape layer. I have another layer compound by a set of points which are the locations where soils samples have been taken within the field. I have in the attribute table of ...
2
votes
1answer
37 views

Using TIN - interpolation plugin - to calculate volume

I am having trouble calculating the volume of my TIN. I have attempted to create a TIN using the interpolation plugin in QGIS. Here are the steps that I followed. I added a Zvariable row in the ...
1
vote
1answer
32 views

Contour generation using Interpolation - Correcting edge Effects

I utilised the Interpolation feature in QGIS to prepare contours from a DEM I had generated. Sometimes when contours intersect the edge of the DEM area, they run along the edge for some distance. ...
3
votes
2answers
54 views

Quality estimation of a spline interpolation with barriers

I interpolated the age of minerals for the Inner Tien Shan mountains (Kyrgyzstan) using the ArcGIS tool "spline with barriers". I use ~ 200 points for my interpolation. The barrier that I use is a ...
1
vote
1answer
172 views

Mapping Precipitation Data

I have downloaded daily precipitation data from Global Weather data website and want to create an annual precipitation map like this: The downloaded data is in TXT and CSV format. The area I am ...
1
vote
0answers
28 views

Maxent output clips to minimum extent of all input variables

I am experiencing an issue with the spatial extent of my output ASC files. I am using the UK Land Cover Map (LCM) 2007 at 25 metres resolution as a categorical variable in my Maxent modelling, ...
10
votes
2answers
2k 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 ...
6
votes
1answer
196 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 ...
1
vote
1answer
80 views

How to create/export multiple maps in one layout using ArcMap?

I have an air pollution data that consists monthly mean values of 12 monitoring stations. I made interpolation and want to export the 12 different map in one layout with one legend. Since I am a ...
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 = ...
0
votes
0answers
24 views

Multiple Z point data kriging interpolation? [duplicate]

I asked this question yesterday and is on hold because I was not specific in my question. I have added my trail code for the question. The question is kriging interpolation of many z. To be more ...
0
votes
1answer
153 views

Why do I get these bands on my Height/Dem/Raster

I can't seem to get rid of them, and I've no idea (ok scrap that, I have a vauge idea) whats causing them. First an apology, yes this is quite a large pic apologies, but here goes: How to ...