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As you have specified that the line from the point can pass in/out of the polygon then I think all you need to do is extract the Envelope of the polygon. You also state in the comment above you are look for an arcpy solution and you have a Basic license level. You can get most of the way with model builder and a sneaky use of the fishnet tool to extract the ...


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"Erroneous" is relative to your accuracy needs. Let us therefore estimate the accuracy in terms of the distance the boat has traveled: by means of such a result, you can decide when positional calculations become "erroneous." I understand the question as saying that mapping is carried out in an azimuthal equidistant coordinate system centered at the boat's ...


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Convert the given polygon into a set of line segments.Find the nearest segment from the given point feature. You can also use ICurve interface to query the farthest edge.


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If you have to measure the distances once again, the following Python code may save you some time. Have your points and lines loaded as map layers. Change the names 'point' and 'line' in line 4 and 5 resp. to the names of your layers. Copy the code into the Python console. The function iterates over all points and finds the closest segment of all lines, ...


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The documentation for Near Analysis indicates "NEAR_DISTANCE: The distance between the input and near feature. The value is in the linear unit of the input features coordinate system, or Meters when the Method parameter is set to GEODESIC and the input is in a geographic coordinate system." So my understanding of that statement is: A Geographic Coordinate ...


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@jmsmcb answered this on Twitter. https://twitter.com/jmsmcb/status/624231773107564545 SELECT *, ST_Distance(the_geom, (SELECT the_geom FROM polygon_near)) as distance_to_polygon from points_near I think this returned degrees, so asking how to get meters or km. And here it is: SELECT *, ST_Distance(the_geom::geography, (SELECT the_geom FROM ...


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This site will calculate 3D GPS positions very accurately. http://www.ngs.noaa.gov/cgi-bin/Inv_Fwd/invers3d.prl I couldnt tell if you were just asking how to calculate a couple points or how to automate the process. To automate i would just make a CURL script to hit this site with your point data.


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Try the Urban Network Analysis toolbox download from City Form Lab. Link to Download/site: http://cityform.mit.edu/projects/urban-network-analysis.html


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It is due to the projection of a 2D plane onto a polorised 2 spheres surface, as the line moves past the poles, it becomes distorted as far as observers of the 2D plane are concerned because the straight line to the destination appears to be a curved ark of a Great Circle, which is a term in mathematics that relates to the greatest circle that can be sliced ...


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Others users might be interested to know that I managed to solve this. In order to extend the lines outside of the polygon (problem a): # Save centre point co-ordinates separately A.x <- Centre@coords[1] A.y <- Centre@coords[2] Using the great answer posted here: http://stackoverflow.com/a/7741655/4312169 I applied the code: # Generate points ...


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I got this working in ObjectiveC. The key here is knowing that you need lat/lng points in radians and you need to convert them back to lat/lng after applying the equation. Also, know that distance and tc are in radians. Here's the original equation: lat=asin(sin(lat1)*cos(d)+cos(lat1)*sin(d)*cos(tc)) IF (cos(lat)=0) lon=lon1 // endpoint a pole ...


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(1) Use GME available from http://www.spatialecology.com/ (2) otherwise use the "Point distance tool" from the geoprocessing tools of ArcGIS - for proximity calculations to find the object distance in the same layer. You can specify search radius. I hope this will help..


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I am no expert in this but from my understanding: The OpenLayers plugin in QGIS uses the EPSG:3857 CRS which is a projected CRS on a flat surface (here's a very good post describing it). Therefore, it calculates a straight-line distance as you would on a paper map. I can't find how Google Maps calculates its distances but a common method would be to use ...


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If I were doing this project, I would ignore GWS but do a bit of data prep before doing an OLS analysis. Option 1: You can generate a "Distance to" field by performing a spatial join on your target layers. If you right-click the Villages point data in the Table of Contents and go to Join... you have the option to "Join data from another layer based on ...


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Here is a Python solution: def displace(self, theta, distance): """ Displace a LatLng theta degrees counterclockwise and some meters in that direction. Notes: http://www.movable-type.co.uk/scripts/latlong.html 0 DEGREES IS THE VERTICAL Y AXIS! IMPORTANT! Args: theta: A number in degrees. distance: A ...


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This seems like a repeat post from your earlier question here, so please don't post twice. Since you mentioned you were working with an ArcView (i.e. Basic) license, I wonder how you're able to use the Point Distance tool, which requires Advanced? For those who have Basic/Standard, ESRI's Near algorithm isn't too hard to implement yourself in Python. The ...


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With out-of-the-box ArcGIS for Desktop, the only way that I think you can do this is by running the analysis using 4,000 metres and then deleting/unselecting from the output table those with distances less than 2,000 metres. Even if a programmatic solution can be developed to ignore rather than write the < 2,000 metre distances and to do that with ...


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You can use the buffer tool (Analysis tools > Proximity) to create equidistant buffers around points. Setting the Dissolve Type to ALL will dissolve the individual buffers into one continuous line feature. Run the tool multiple times to create buffers for each distance you need. If you need buffers around only a subset of all the points, I recommend ...


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This may be a bit more work than you want to do, but if you edit the layers with advanced digitizing enabled, you can create a new feature starting at a point and as you move the mouse around to other points and positions the distance is displayed in the advanced digitizing panel. You can then copy down the ...



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