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

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3
votes
1answer
268 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 ...
1
vote
1answer
214 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 ...
3
votes
1answer
236 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
1answer
138 views

Interpolation with netcdf4 file

I have a netcdf4 data set that contains array and information about latitude and longitude which can be accessed with the following R command: ncvar_get(dataname, 'lon'); ncvar_get(dataname, 'lat'); ...
2
votes
0answers
102 views

How to calculate the grid point precipitation from the station data?

I have a problem to convert my hourly station precipitation data to the surrounding grid points. I need to convert 4 station hourly rainfall data to 18, 60, and 240 grid points for 0.0625,0.03125, ...
3
votes
0answers
183 views

Create a path following a road, interpolating from a set of points

I have several hundred vehicular routes within a city from which I wish to create shapefiles. These take the form of directions such as "From Green Street, turn left into Brown Street, Right into ...
0
votes
0answers
78 views

Mapping point data according to it respective value

The project I am trying to do is to map sum water quality (based on trace metals) data into QGIS. Each of the trace metals have their respective values and need to represent their concentration ...
1
vote
1answer
80 views

About Interpolation Method using GIS10?

I have attached my stream network where the green dots shows the location with discharge gage now I want to create a raster all along the stream network to have a discharge data all along the river. ...
1
vote
2answers
872 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
2answers
278 views

minimum distance from the shore (how to retrieve the “shore vertices”)

I am student of Statistics, this is my first time using GIS., I am sorry for the stupidity of the question but I browsed online and could not find a satisfactory answer. I have some spatial data in ...
0
votes
1answer
119 views

Best interpolation tool for thickness points

I'm using Arcmap 10 and I have scattered points (denser in an area). Each point represents a thickness value. I want to get a raster from this points which I will transform in polygons ...
1
vote
3answers
284 views

Multibeam bathymetry xyz data 53000000 features arcgis 9.3

Im working with an xyz file that has 53000000 points, i have only been able to see this in Microsoft access, because in txt its says that the amount of data its too large. So what i´ve tried to do: ...
6
votes
6answers
502 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 ...
0
votes
1answer
94 views

How to add information to an attribute table?

I'm working with qgis 1.8.0 and did the following: 1.-Divided my shapefile into 830 features (small rectangles). 2.- Added to my shapefile several points containing weather information using the "add ...
0
votes
0answers
283 views

Code to compute weights for Inverse Distance in C#

I want to test my data using IDW in C#. As I am new to C#, can someone please help me by providing the code to compute the weight for the point?
4
votes
2answers
193 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?
0
votes
1answer
48 views

Sampling from interpolated data layer

Im working with QGIS 1.8.0 and wanted to ask you how can I assign to each of the small squares of the map (I have the coordinates of the center each of them) values from an interpolated data layer as ...
-2
votes
1answer
136 views

Interpolation of data

I'm new with the program and I want to know if I can use it for my master thesis so I was trying it out and have the following question: Is it possible to interpolate data out of 5 weather stations ...
0
votes
1answer
95 views

Problem with interpolation of 3D points in GRASS

I have a sample of 3D points (x,y,z) with tepmerature attribute. I can import my data as a 3D vector map. I want to create a volume of voxels by using v.vol.rst. When I use this module, this error ...
0
votes
1answer
180 views

Convert / interpolate delimited text csv points grid to surface

I've got 12 delimited text csv files with regular pseudo-gridded points for temperature and salinity which look like this when zoomed in (inc distances) and this when zoomed out. I'm trying to convert ...
0
votes
0answers
262 views

Which is the best interpolation method for collected ground water sample?

I have collected ground water quality samples from 50 locations in my study area. Now I have to interpolate data in ArcGIS. Which is a suitable method for ground water interpolation and why?
0
votes
2answers
411 views

How can I get an error map of an interpolation in ArcGIS?

I have about 10 point shapefiles containing a lot of points each. (I would prefer not to join them into one shapefile, it's pain). And I am using interpolation method Topo to Raster to create a DTM. ...
1
vote
0answers
407 views

Error #010067 when running spline interpolation

I am attempting to run a spline interpolation on a point dataset of 585 features in ArcGIS 9.3, using the spatial analyst toolbar. The dataset holds only latitude, longitude and abundance attribute ...
0
votes
1answer
120 views

interpolate point values to line

This might be a stupid question and I apologize if so. I have count data for different trails. They are points and I would like to make an average of those counts for each trail so that each trail has ...
4
votes
2answers
131 views

How to (vertically) register a DEM to GPS readings?

I don't know if what I ask is possible or not but let's try... I have two datasets: a DEM as a point cloud in a relative coordinate system, constructed with 3D algorithm structure-from-motion. 20 ...
-2
votes
1answer
201 views

What tool(s) in the Sextante toolbox in qgis 1.8 can be used for interpolation? Kriging and spline

I have looked at every single one and can not figure out which on can be used.
1
vote
0answers
451 views

Validation of Regression Kriging

I am interested in exploring the idea of generating a predictive model for a target variable in a spatial context. I would then like to correct the residuals of this model using kriging, i.e. in a ...
4
votes
0answers
88 views

Estimation of values for unsampled points

I want to measure biomass on a coastal mudflat. I can only access points inside the polygon. Are there any methods available that would allow me to estimate values of the points outside of the ...
1
vote
0answers
357 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
236 views

Diffusion/Kernel Interpolation with barriers? [closed]

I need to interpolate water quality data in a rather small area with peninsulas, islands and developed coastline that will act as barriers between my testing/sampling points. I understand I have to ...
0
votes
0answers
90 views

How to spatialy interpolate forest tree height, basal area data for certain species

I have ecological sample data collected from 5 locations within a 133345678.5678 sq meter area. The data is stored in a point shape file. I have joined tabular data with the point layer by duplicating ...
1
vote
0answers
50 views

Generating “weighted convex hull”

sadly I don't have any keyword that reflects what I'm looking for: I have a vector layer consisting of points, which have an integer attribute ("signal quality" here), that I want to plot as a convex ...
1
vote
2answers
135 views

contour lines from point shape attribute

I have a point shape file and one of the attribute refers to the altitude. Is is possible to obtain a contour lines shape file in GRASS?
2
votes
1answer
312 views

How to interpolate GPS data correctly?

I'm working on a project that involves using linear interpolation to fit lines to lat/lng points. I'm pretty new at scientific programming related stuff, and I was wondering if people could steer me ...
1
vote
0answers
84 views

Limiting the maximum and minimum values of an interpolation surface tool (ArcGIS, Spline)

I've been using the spatial analyst spline tool in ArcGIS 10.1 and was wandering whether it is possible to limit the maximum and minimum values to those of the z-attribute. Currently the spline will ...
6
votes
1answer
352 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 ...
7
votes
2answers
278 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 ...
1
vote
1answer
196 views

IDW: Default Maximum Distance and Coincident Points

The ArcGIS Help file says the Default Maximum Distance, when using the Variable Search Radius in IDW, is the extent's diagonal, however, no value is automatically filled in the corresponding box after ...
1
vote
0answers
151 views

Plotting time-series data in ArcGIS

I'm attempting to produce interpolated plots of water quality time-series data from ArcSDE. This is the data format: OID WELL_ID WELL_NAME SAMPLE_ID SAMPLE_DAT PARAM RESULT ...
0
votes
4answers
133 views

How to clip rasterdata for later processing?

My need to dwell with geographical tools is only temporary, thus I am not well versed and my question is difficult to pinpoint exactly. But here it goes: -I have about 5-10 sites, for which I need ...
1
vote
0answers
317 views

“topo to raster” tool

is there any analogue of "topo to raster" tool (ArcGIS) in QGIS? I need to creates surfaces from shp for some cases from points and for some from lines and this instrument is very convenient.
2
votes
0answers
386 views

z-Coordinate and interpolation plugin in QGis

I've a csv file that includes weather stations locations (x,y,z) and precipitation values. I loaded the file by using add delimited text and then converted it into a point shapefile WS84. By using the ...
3
votes
1answer
227 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 ...
1
vote
1answer
78 views

Tranform Lat/Long NASA points into raster

I have this irradiation file and I would like it to upload it in ArcMap in order to overlay it with other layers to do clips, intersections, etc? ...
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
1answer
753 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
290 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 ...
2
votes
0answers
118 views

Interpolate current Course value of GPS using previous Course values

I have a set of GPS data with Lat, lon and Course. I need to interpolate current value of course, using previous values of Course. The formula I am using is not accurate in curves.In C language I was ...
4
votes
1answer
305 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 ...
2
votes
1answer
372 views

Inverse distance weighted interpolation for categorical and/or binary datasets

I want to perform an Inverse distance weighted (IDW) interpolation to a series of points. However my data set can be categorical or binary and just like the IDW I want to interpolate the new values ...