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

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65 views

network based interpolation methods, which one could I use?

I need to interpolate traffic data consisting in raw number of vehicles passing across certain points, where counters are. It is evident I haven't a uniform distribution of points and values about ...
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13 views

Convert ECF to Suface ECF

I'm using the 3D Earth WorldWind Model and I have a path that I want my object to travel. I set the the destination and interpolate to the end point from my current location. The problem is using ECF ...
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2answers
127 views

Color gradient in symbology in ArcGIS 10.1 for interpolation raster

I have measured noise and want to create with this measured points a noise map with interpolation....is there any way in symbology to create a flowing transition between the different colors for the ...
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2answers
78 views

How to interpolate population data?

I have population data (inhabitants per city and year) of 31 cities of the DR Congo for the years 1960, 1970, 1980 and 1990. I want to interpolate the population of all cities for the year 1990, to ...
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1answer
68 views

problem in spline with barriers in ArcGIS 9.3?

I am trying to use the script tool "Spline with Barriers" from arcgis 9.3 3D Analyst toolboxes. I am not getting expected output. The output is just only one value over the surface. We are using ...
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2answers
70 views

How to perform IDW interpolation and mean estimation on county level using ArcGIS for Desktop?

I am absolutely new to GIS. I have imported a map with information in the counties of Germany. Additionally I have added a layer with information on SO2 concentration at various measuring stations in ...
4
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1answer
154 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 ...
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1answer
106 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 ...
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3answers
221 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 ...
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12 views

Printing a label from a point layer attribute on a raster layer (GRASS)

I am interpolating with boundaries using v.surf.idc in GRASS. It works wonderfully and I fully recommend it. I am creating an animation and I use v.surf.idc to generate sequential interpolated raster ...
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1answer
210 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 ...
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2answers
327 views

What's wrong with my IDW interpolation function (Python)?

Original Question Can anyone see what's wrong with my custom IDW interpolation below? I know there are existing libraries that can do this for me, but for various reasons including educational and ...
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90 views

References to code IDW algorithm

Hi I'm new to interpolations. I'm looking for documentation to understand how inverse distance algorithm works and how to code it. My intention is to code IDW algorithm in JavaScript to see if it is ...
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1answer
53 views

QGIS 2.0 Raster Interpolation

I am trying to use the Rasterinterpolation plugin to pick up elevations from a Raster DEM for a series of vector points. Once loaded, the Plugin is accessible through Plugins Menu/ Raster ...
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2answers
185 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, ...
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2answers
28 views

attach point grid data non-grid points

Possibly a strange one: I have a dataset with loads of fields of environmental (explanatory) data, as a regular grid of points (black dots in image), and another dataset of sampled (response) values ...
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1answer
31 views

“Interpolation Toolset” is inactive in ArcGIS for Desktop 10.1

I have ArcGIS for Desktop 10.1 installed on my laptop and "Interpolation toolset" and "Raster Interpolation toolset" is Inactive. How can I get them work?
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3answers
161 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 ...
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1answer
98 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 ...
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0answers
393 views

smoothing results from scipy griddata interpolatioin

I am using the griddata interpolation package in scipy, and an extrapolation function pulled from fatiando: import numpy as np import scipy from scipy.interpolate import griddata import ...
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2answers
401 views

How to interpolate a point vector layer inside a boundary (polygon layer) QGIS/GRASS/SAGA?

I have a to create a heatmap of water temperatures inside a lake for which I have sample points. The map should look much like the climate maps generated by climate change models. I have the ...
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2answers
91 views

How to set lower limit to interpolation?

I have rainfall data that I want to interpolate using spline. I have done Spline Interpolation, only that the values produce negative predicted values which is basically wrong. There should be no ...
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0answers
21 views

Interpolation Plugin Not outputting image?

I am trying to get terrain profiles from shapefile elevation points by creating a TIN. I have been following this very helpful tutorial. At the output a new layer is created but with no ...
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170 views

How to write Python script for spatial interpolation?

I am new to Python. I have 5 rainfall stations in a basin of 1400km2, and I want to interpolate the daily rainfall series for 14 years. I spent a long time on this, but am unable to write a program ...
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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 ...
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53 views

TPS and Kriging Cross-Validation

I am looking for existing package or functions that will allow me to cross-validate multiple outputs of Thin plate spline (TPS) and Kriging from the fields package. Does anyone know of any availabe ...
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2answers
49 views

Which value should I assign my digitalized features?

I have a scanned an old document that contains geochemical interpolated values (no way to work with the digital file). This is the original image: And this is the digitalization I made from it: ...
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262 views

SAGA/GDAL fails to open grid in QGIS 2.0.1 on OSX 10.6.8

I want to try different grid/raster spline interpolation methods using SAGA in QGIS. I'm using the kyngchaos build 2.0.1-7 for Snow Leopard. Every SAGA algorithm I try gives the following in a popup: ...
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1answer
82 views

Finding points on an odd map projection using interpolation between known points

I have an image of a somewhat idiosyncratic projection that is a frame from a film: A geographer friend of mine said it was probably some kind of Gnomic projection, but that from the resolution it ...
3
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1answer
174 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 ...
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1answer
115 views

3 points meteorology stations

I want to extract meteorological data of a point which are 3 meteorological stations around it. I found that ArcGis has the capability to do it by interpolation. My essential data is wind speed , ...
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2answers
79 views

What ArcGIS interpolation tool would be most appropriate for price/square meter?

I have the price per square meter of around 13000 properties ; for the other 8000 of my shapefile the price is missing. The easiest option is to transfer the average price per square meter to the ...
2
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1answer
113 views

How to integrate DEM in Kriging and other interpolation methods?

I would like to see the difference of including DEM in interpolation from without. Some studies on climate data interpolation suggest that interpolation performs better with DEM. How do I do this in ...
4
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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 ...
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1answer
70 views

Interpolation without a point layer in QGIS

I have a vector layer with incidence data (i.e. frequencies) and I made a graded color map from this using the above frequencies. Now I am looking forward to creating an interpolated (kriging) map ...
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67 views

Interpolation Technique

We have following solar metro logy parameter through satellite data with resolution of 100 Km^2 (10Kmx10Km) Insolation on horizontal surface Diffuse radiation on horizontal surface ...
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0answers
185 views

Interpolate/disaggregate point values to an existing raster grid

I have several thousands of ASCII files whose names have the following format: data_"lat"_"long".mon (e.g. data_41.21875_-116.21875.mon). Each file represents one point in WGS84 projection and the ...
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0answers
69 views

Interpolating counts within irregular-shaped regions in a country?

GIS novice here. We are trying to estimate the total number of toxic waste sites within the country of Ghana. We will be dividing up the country into quadrats (with some irregular shapes on the ...
3
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2answers
183 views

How to connect contour lines from two different sources?

How to connect contour lines from two different sources (LiDAR & Photogarametry) in order to obtain continuous and uniform contour lines layer ? how can i interpolate them together ? How can i ...
2
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0answers
202 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. ...
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1answer
60 views

Is it possible to specify interpolation method for zoom functions in Styled Layer Descriptor (SLD)?

To visualize images on Geoserver, I use xml file wrote in Styled Layer Descriptor (http://www.opengeospatial.org/standards/sld). I would like to specify what interpolation method would be used for ...
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1answer
99 views

How to consider more than one no data value in utility gdalwarp of GDAL

I have to do a bilinear interpolation on an image with two no data values, using the utility gdalwarp of GDAL (http://www.gdal.org/gdalwarp.html), so these two values don't must be considered in ...
0
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1answer
187 views

Problems with interpolating in Arcmap 10

I would be extremely grateful if I can get help with this question. I cant find anyone who had a similar problem. I am trying to make a raster from point data. My data is in .txt form and contains of ...
3
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3answers
836 views

Best way to assign points to nearest roads in postgis?

I'm trying to implement a simplified type of dasymetric mapping for census data. I've downloaded the Census's American Community Survey individual-level data and randomly assigned every household to a ...
3
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2answers
120 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 ...
4
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0answers
218 views

Weather conditions forecasting / interpolation

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 ...
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 ...
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1answer
160 views

How to interpolate daily climate data using ArcGIS for Desktop? [duplicate]

I want to interpolate daily climate data available from 3 locations. I am not sure how to interpolate the data for daily values for 30 years from the available 3 locations.
2
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2answers
407 views

Interpolation iteration using ArcGIS- arcpy

My current project requires interpolation of state level weather data. Approximately 5 years of daily data needs to be interpolated. I still need to figure out the best interpolation method. However, ...
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111 views

Weather interpolations QGIS

does any one know how good are the weather interpolations that QGIS carries out? Do you have any other suggestions or better methods to do them? Please let me know. Thanks in advance!