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

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20 views

Radius settings under IDW interpolation Qgis [on hold]

I have a point data set that I want to interpolate in Qgis. I use the Grid (interpolation) under: Raster- analysis- grid(interpolation) - IDW. There is several things to tweak the output with that I ...
2
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1answer
27 views

Relationship between contour interval and spatial resolution of a generated DEM

If I have contour lines with interval say 10, 5, or 2 (etc.), and I generated a DEM from them, what is the relationship between between the contour interval and the resolution of the DEM? Irrespective ...
3
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1answer
61 views

Strange spatial interpolation results from ordinary kriging

I'm using Ordinary Kriging to interpolate a set of spatial data. I'm working on different sets which represent different days of measurement. I get good results, apart from one specific set. Will post ...
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0answers
42 views

QGIS interpolation gives same value across the grid, what am I doing wrong?

Following this question, I've tried to use interpolation in QGIS to get a sense of the topography of a map based on about 3500 track points with elevation. The elevation ranges between 213 and 353 ...
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0answers
21 views

Strange interpolation with natual-neighbor metod

I have base shape file and try to use different interpolation methods to get image like this: This layer is constructed using point to raster conversion. Generally, interpolation methods as idw ...
2
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0answers
22 views

Expand data set by interpolation

I have a data set that is classified into 7 landcover classes. I've been asked to expand this data set to a new boundary. My question is How can I interpolate my existing data out to meet the new ...
2
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1answer
43 views

How to interpolate line Z from sparse attribute values

I have a series of end-to-end connected 3d lines which I'd like to add elevation values for all vertices on the lines which are currently null or 0. How to accomplish this? In the following image ...
2
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1answer
25 views

Why does the use of barrier lines significantly increase idw processing time?

The IDW tool's documentation states that using barrier lines will significantly extend the processing time. It does not explain why this happen. Is anyone able to provide an insight into the inner ...
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1answer
66 views

Can we create topographical map of private land using GPS elevation data?

Is there a way to create a relatively precise topographical map of a private land using GPS elevation data? As the land is a little bit over 100,000 square meters, the available regional topographical ...
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2answers
63 views

Kriging values greater than the most extreme value of the input layer?

I'll admit I don't understand kriging to the fullest. Yet, I've read that the weights should add up to 1 as in IDW and Natural Neighbors. However, surrounding the biggest elevation points of my ...
1
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1answer
43 views

Interpolating points conditionally

I have two sets of data. One comprises all home sales in a given area, where each data 'point' is actually a polygon representing the lot that was sold. The other set comprises arrests made in the ...
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1answer
28 views

Unit of measurement from standard error prediction map

I am performing an ordinary kriging analysis and came out with the prediction standard error map. I would like to know the units of such map. Can anyone help me?
4
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1answer
46 views

Difference between “hard edge” and “soft edge” in Arc's Add TIN Line?

Is there a technical difference between "hard edge" and "soft edge" in Arc's Add TIN Line on the TIN Editing toolbar? In both you can specify the height of this constraint and they seem to be doing ...
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0answers
18 views

Attempting to interpolate from samples rather than known observation. What kind of analysis is this?

I'm trying to figure out what the name of the kind of analysis I'm thinking of is, and what options in programs to check out (mainly ArcGIS or QGIS). I'm a bit of a beginner when it comes to ...
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0answers
36 views

How can I use a csv file with coordinates and multiple attributes to extract interpolated values for a different set of coordinates in ArcGIS?

I have a .cvs file of 501 rows that correspond to 500 coordinate points, with each row consisting of latitude, longitude for a single location, followed by a list of about 100 weather attributes ...
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0answers
32 views

How do Natural Neighbor and IDW assign values to pixels?

According to ESRI's help files, NN interpolation calculates a value for a "query point", yet the output is ofcourse a raster. I understand how the value of this query point is calculated based on the ...
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0answers
27 views

Leave-one-out cross validation in ArcGIS Desktop?

How can someone perform leave-one-out cross validation when doing interpolation in with point data in ArcGIS?
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0answers
10 views

NCEP Reanalysis Interpolation over regions

Given a netCDF4 file, how would one interpolate/average the data by regions in a shapefile? In reference, the publication below: ...
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2answers
47 views

Which training courses in geostatistics can you recommend?

I'm looking for excellent geostatistics courses all over the world, including online courses. In particular, I would like to learn more about the kriging method. Can anyone give me some suggestions?
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0answers
30 views

Never get the information about obective interpollation and optical interpollation

I have point data want to interpolate it and convert it into 3d grid format but i am not get any proper information which interpolation i have to used objective / optical. please let me know any ...
2
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1answer
37 views

Interpolation code with Mapbasic

I have a drivetest data, and usually I do an interpolation using the values taken in the drive with their respective lat/long. I use natural neighbor. You can see an example attached. I am trying ...
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0answers
33 views

Calculating minimum elevation surface between two (or many) surfaces

My input files are a series of layers with data points of values (numbers/doubles), either in a 25x25 meter grid, or with data points randomly strewn. Resolution and extents do not match up between ...
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0answers
38 views

Cross validation after kriging, in ArcGIS

I performed kriging interpolation using the kriging interpolation tool in ArcToolbox, not the Geostatistical Wizard method. However, how do I determine the cross validation without using the ...
4
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1answer
84 views

Spatial interpolation of 30 weather stations to other areas

I have monthly (and sometimes daily) data on temperatures from about 30 Swedish weather stations in the mid-19th century that I want interpolate to the whole country. I'm using ArcGIS and Stata. For ...
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0answers
36 views

Gradient fill based on scores (similar to elevation)

I'm rather new to using GIS (QGIS, specifically). I've mapped out a cohort of around 550 patients across Long Island, New York based on their full address by using MMQGIS plugin. This data is ...
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1answer
103 views

Interpolation and classification of soil texture data

I am trying to interpolate soil texture data on a research area. I know how to interpolate the data by making three layers for clay, sand, and silt. What I want to know is if there is anyway to ...
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90 views

Interpolation using GDAL

I am looking for some hints here. There is a shape file with point data of rainfall sampled at a regular grid, and there is a shape file with point data of soil attributes sampled at a regular grip ...
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0answers
43 views

Calculate surface map from PostGIS

We need to create surface maps from the website. The data is stored on PostGIS (2.1) as a table of Point geometries with a field indicating a thematic value. The optimal solution would be to produce ...
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1answer
38 views

Feature Class Iterator in ModelBuilder

I am hoping to run a simple Iterator operation in ModelBuilder, but everything I attempt is not producing the right results. I have a Geodatabase with many point files in it. I want to run and ...
1
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1answer
58 views

Setting lower and upper limits to classes in kriging interpolation, ArcGIS

I am using the kriging interpolation tool. I included two dummy values within my dataset:- an upper limit and a lower limit. I ran the tool in arc map 10.1 software. However, I want to change the ...
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0answers
58 views

Spatial Interpolation/Resampling of Point Surface Data - Axes @ Different Resolutions

I have a simple set of data points in x,y,z format. This was data collected from a ground penetrating radar over a physical distance of: 45m x 25m With a resulting grid of: 90 x 100 (9000 points) ...
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0answers
25 views

Problem with QGIS raster interpolation from a point shapefile after duplicating the shapefile

Let me explain a problem I had with QGIS to see if somebody else has experience it. I created a raster from a point shapefile through the Raster-> Interpolation menu with no problems. After that, I ...
1
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1answer
39 views

QGIS raster from interpolation not scaled correctly

I am using the interpolation plugin in QGIS to interpolate values within a boundary. I start with two layers; 1) my points and 2) a polygon for the area of interest. Then I go to ...
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0answers
49 views

Does interpolation create a vector or raster?

I have been reading about interpolation and am trying to understand whether interpolation results in a vector or raster. Say I have a layer of points and I am interested in creating a raster that fits ...
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9 views

Finding polygon from two arcs using CLI tools or some library

I'm trying to convert from textual representation into a set of arcs and lines. The 'input' I have is: The area is within lines joining two semicircles with a radius of 0.67 NM centred on: 641139N ...
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1answer
57 views

Creating an R factor raster in RUSLE Soil Loss equation with multiple input rasters

I am attempting to obtain the rainfall erosivity "R" factor for the RUSLE Soil Loss equation using rainfall PRISM 30 year history data. I have both monthly and annual data that comes into ArcMap as ...
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0answers
47 views

Optimal distance and power exponent in IDW

I want to apply IDW interpolation for my region of interest, and through leave-one-out cross validation I want to find the optimal values for the distance parameter and the power exponent. I know that ...
0
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0answers
30 views

To combine attributes of point data with different spatial reference

I have rainfall data (gridded data) for a region at 25 km and other variables (max and min temperature, solar radiation and wind speed) at 35 km in ASCII format. I converted them to point feature ...
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1answer
24 views

MODIS MOD10A2 snow product

I have extracted pixel value ( pixel value=200 for snow) from MOD10A2 snow product for my study area. Since MOD10A2 product is distributed every 8-days. i.e., 9th Jan, 17th Jan, 25th Jan,2nd Feb,.... ...
1
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1answer
64 views

Interpolate value at a specific point using kriging

Is it possible to interpolate the specific value at a point using the Kriging tool in the spatial analyst toolbox? If not, then, how can this be done in Arcgis? To my knowledge, Arcgis only produces ...
2
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1answer
46 views

Create Raster Surface from Points and Equations in ArcGIS

I want to use point data to create a raster surface which distributes the values over space, as defined by an equation, and NOT by interpolating. I have an equation to describe how the characteristic ...
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0answers
37 views

Interpolated raster not aligned with the vector data (QGIS)

I have loaded some tab delimited text data into QGis to interpolate the points. When I get to the interpolation (IDW) part everything breaks down. The output raster file does not align with the ...
2
votes
1answer
52 views

TIN Interpolation in QGIS creates weird lines?

I am using TIN Interpolation to interpolate point features based on their cost attribute (value is between 0 and 5000). Graduated symbology creates something like this: However when I am using TIN ...
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0answers
31 views

ArcGIS export hgt/srtm

I just resampled an hgt-file using ArcMap of ArcGIS for Desktop. Is there the possibility exporting the resampled data as hgt file again?
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0answers
37 views

Interpolation of SRTM data

My situation: I need to interpolate the 3" srtm data for a game I'm developing (it's like Minecraft - voxel style). I downloaded the srtm data from viewfinderpanoramas.org. My aim is to get the height ...
2
votes
1answer
40 views

Looping for importing and interpolating a lot of LIDAR files?

I'm quite new to Grass Gis and I'm trying to make DEM (digital elevation model) for modelling flooding. I have 170 *.xyz files, which need to be scanned for extents (r.in.xyz -s input=...\filename.xyz ...
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0answers
36 views

Hydrological triangle (geoscience) with QGIS 2.6.1

I want to interpolate ( TIN-Interpolation) between variable points (the best within a triangle) WITHOUT producing new shapefiles (or csv data file). So what I have now is an interpolation of all ...
0
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0answers
20 views

How to change the angle of the gradient lines in local polynomial interpolation?

I made a map with river salinities using 5 data points. When I did the interpolation the gradients come up looking beautifully but because the river is at about a 45 degree angle to the north-facing ...
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0answers
56 views

Kriging metal concentration with irregular set of sample points

I need to perform some interpolation to map a metal concentration around a platform. The distribution of my stations is not regular (see figure below where stations are the green points labelled with ...
1
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1answer
40 views

Comparing 2 contour data set files

I have 2 feature class files of contour lines for an area of interest - from 2 different sources. We would like to select just one to use and I'm looking for any methods to effectively compare the ...