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6

There is a nice tutorial on segmentation of spatial lines which you can find here, and you could make use of CreateSegment to achieve your goal. But first of all, let's create some sample data. ## german borders library(rgdal) library(rworldmap) data(countriesCoarse) spy_germany <- subset(countriesCoarse, GEOUNIT == "Germany") ## polygons to lines ...


5

This function will create a systematic point sample of a SpatialLinesDataFrame. The LID column in the results corresponds to the row.names of the source line object and can be used to relate the points to the lines. # Function for creating a systematic point sample of a SpatialLinesDataFrame # x SpatialLinesDataFrame # sdist ...


4

So, you have a point feature class. Every point has a unique attribute that represents the sequence (e.g., from 1 to 100). You want to get a point with PointID = 1, find a distance to the point with PointID = 2, and write this distance value into the Distance field in the feature class (Distance field for feature PointID2 will contain the distance from ...


3

I have made a tool that does this measurement. This tool needs only three parameters: Just download the Measure_Length.tbx and locate in the ArcCatalog and run. Input Point Feature Unique field (in the attribute table) A field that will be populated by this script, data type for this field must be double Please find the tool in the github at here. ...


2

Is there some way to correct this? As you've correctly identified, using spatial adjustment in ArcMap will help adjust the points in your shapefile. From the document About spatial adjustment Start ArcMap. Create a new map or open an existing one. Add the data you want to edit to your map. Add the Editor toolbar to ArcMap. Add the Spatial Adjustment ...


2

I don't know that either would be 'more correct'. I would probably lean toward random points, since any regular spacing might introduce bias based on the pattern. You do not want an equal number of points. See http://en.wikipedia.org/wiki/Modifiable_areal_unit_problem Three samples of a large variable polygon might fall on values the same as a uniform small ...


1

The SpatStat package has a function for creating points along lines at specified intervals. # maptools to read shapefile require(maptools) require(spatstat) # Load a line shapefile myLine <- readShapeLines("~/workspace/TEMP/myLine.shp") plot(myLine) # create a PSP object to use with spatstat myPSP <- as.psp(myLine) # Create points at 10 km ...


1

The CID values represent the FIDs of the features in which the random points were generated.


1

Thank you for your help! (Nathan helped me on the QGIS issue tracking page with the same advice he posted here and that mapBaker also posted). I added a unique int column to this table and then it loaded the layer with no problem. Thanks again.


1

Here's a link to download the Create Grid Corner Points tool View the source code: click me Basically, for each polygon it gets it's extent, and then finds which vertex is closest to each corner of the extent. This really only works well for squarish shapes. It would not work on something shaped, for example, like a diamond. The output point feature class ...


1

The general problem here, known as polygonization in the literature, is quite difficult. See, e.g., this web page. The problem with the convex hull is that the region outlined by your points might not be convex. And in fact, you could lose most of the detail:           Above, the convex hull of the circled points is the ...



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