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2

I would approach this as follows: Convert your polygons into lines (by which each edge of the polygons - a line between the consequent vertices - will become a line feature in the output feature class.) After the conversion, the output lines will preserve their "parent" polygon ID. Use GP tool: Feature To Line. Take each point and then find out which line ...


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Thank's guys, I have solved my problem. IPolygon4 polygon = buld_F.Shape as IPolygon4; IGeometryBag exteriorRingGeometryBag = polygon.ExteriorRingBag; IGeometryCollection exteriorRingGeometryCollection = exteriorRingGeometryBag as IGeometryCollection; for (int i = 0; i < ...


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The Devil, of course, is always in the details. You need to look at several things. First the river itself: You talk about 'a' river. It sounds as though you are talking about land use along specific reaches of a single river. Is that the case? Second the bank: Are you interested only in the land use along one bank of the river? Then the ...


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Agree with Chris W. This field calculator expression will calculate from and to measures in a point file, providing there is a single river - polyline: def CalcFromToMeasures(shp,n): mxd = arcpy.mapping.MapDocument("CURRENT") lr=arcpy.mapping.ListLayers(mxd, "river")[0] with arcpy.da.SearchCursor(lr, "Shape@") as cursor: for row in cursor: ...


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Both variables are zonal means. The average distance to the nearest facility is the zonal mean of the Euclidean distance grid (based on the facilities). The average number of facilities is the zonal mean of a one-kilometer radius focal sum of the facilities grid. (This is merely a grid whose cell values count the number of facilities within each cell. ...


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You can follow through with the Downey method and raster. Since step one is done (polygon to raster your census tracts) you move on to step 2. First up will be Raster to Points to get a set of points that represent each raster cell. Once you have those you can use the same Spatial Join methods you would on the census tracts - after all, you're just trying ...


1

If I understand your question correctly, it sounds like you are trying to plot the relationship between size of wetland and distance to your sample points. I don't think there is a single tool that will do what you want in one step. The Near tool in the Proximity toolset will calculate the closest distance to the other feature. The point distance tool will ...


2

Your database is not really a SpatiaLite database but a SQLite database which contains geometries which are encoded according to FDO specification. Something about FDO can be read from http://trac.osgeo.org/fdo/wiki/FDORfc16. Some other software, like TatukGIS, are also creating SQLite databases with FDO geometries. Spatialite can read FDO geometries ...


2

You'll need to use Network Analyst for this. The first thing you will need to do is turn your lines into a network. The Network Analyst Tutorial exercise 1 covers this, but be aware it may not go into sufficient depth, as there are geometry and topology considerations to take into account. Why isn't the service layer shape properly spread out? touches on ...


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Unfortunately I have egg on my face with this one...although this was my first thought I ruled it out like an idiot due to passing in my parameters backwards...Thanks everybody http://stackoverflow.com/questions/29669045/postgis-st-distance-query-returning-inaccurate-results


2

Converting your polygon to points first is a bad idea. You will not be calculating the distance to your polygon, you will be calculating the distance to the closest node of your polygons (not the edges which may be closer). You can use the NNJoin Plugin to get accurate measurements to your polygon. Make sure your layers are in the same projection before ...


1

I suspect that your google SRID may be incorrect. I believe that google geocode results use SRID 4326 (WGS 84). I believe the google uses 3857 for the map display, but outputs the data as 4326.


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I did a quick glance at the code for the tool. It appears that default/feet choice is to specify a fixed conversion between feet and meters. This would make sense, because as I mentioned earlier in the context of metes-and-bounds you're usually using one of those units (or something archaic like chains or rods). But line 189 of the source code is just a ...


4

The radius, r, of the small circle joining all points at latitude, φ is r = R cos φ where R is the radius of the sphere. That simplifies to r = cos φ if we assume a "unit sphere" (R = 1) for convenience. --------------------- A/D | r φ / | / | / | / |a / |x / |i ...


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Thank you everyone for the input and comments. If I understand correctly, Alešinar, you are pointing out that it is problematic to derive cost values from a vertical factor table using the Path Distance tool if your input cost is based on a raster expressing only positive slope values. In other words, for the Path Distance tool to derive cost values, the ...


4

It doesn't matter at what longitude you are. What matters is what latitude you are. Length of 1 degree of Longitude = cosine (latitude in decimal degrees) * length of degree (miles) at equator. Convert your latitude into decimal degrees ~ 37.26383 1 degree of Longitude = ~0.79863 * 69.172 = ~ 55.2428 miles More useful information from the about.com ...


1

I encountered this same issue while working on my thesis, and was able to adapt an existing tutorial to the tools available in ArcMap 10.0. I recently added screenshots and other information to clarify, so I feel it is pretty straightforward: http://kaitlinyanchar.com/arcgis-tutorial-toblers-hiking-function/ I am the author of this website.


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I came up with the table for Tobler values posted on MapAspects in 2009 (in ArcGIS version 9.3) and after a few hours struggling with Path Distance in Arcmap 10.3 my conclusion is it's broken in the current version. Even their example table on the Esri help file produces the same transformation as a bunch of 0 values. I've tried various values and while ...


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You could use the open source GraphHopper routing library. Very easy to setup and query via HTTP. (Note: I'm the author) We also offer a commercial Matrix API based on Gramaking such queries very fast but 1-2 would be only possible for something like 50 locations. More will take longer. Also we offer up to 1000 locations, but only for custom packages.


-1

Check geosphere package distance function or fossil deg.dist function. You have data in degrees and need to translate it into meters or feet before doing clustering.


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The thing that you want to do is to solve Travelling Salesman Problem or one of its variations. 7000 points is a very difficult task. And you may spent a lot time calculating it (depending on software and algorithm) There is an open-source implementation of Genetic algorithm (not the most advanced one) in pgRouting extension for PostGIS. Another option is ...



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