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12

This is a perfect task for the linear referencing capabilities in ArcGIS. See the help for Locating Features Along Routes and probe from there. The tools include the ability to turn a layer of points near a route (the river reaches) into "point event" descriptors, which name the route (the reach) and the distance from the beginning of the route. That's ...


10

Found this in the FDO data concepts page: A geometry is represented using geometric constructs either defined as lists of one or more XY or XYZ points or defined parametrically, for example, as a circular arc. While geometry typically is two- or three-dimensional, it may also contain the measurement dimension (M) to provide the basis for dynamic ...


8

The other option that I have found is using PostGIS. This software provides the spatial extensions for the PostgreSQL rdbms. These are both Open Source. There is a Linear Referencing Component described here: Link. If you want to be able to access this functionality through a more full-featured GIS program, then you might use the Linear Referencing ...


7

Since you are already symbolizing by road condition (which I'm guessing may be represented by a few colors), I would suggest to not use a multi color dash line to represent survey origin (sometimes less is more). I generally use a buffer/fade effect for displaying multi attribute line info, see caption below.


6

An alternate method is to use the haversine formula, since you have the lines in a shapefile, you can use QGIS to extract the begin and end points to calculate the bearing. Once you have the bearing and the distance from the origin, you can calculate the end point. This all doable in excel as documented here: ...


5

For Java, I'd recommend JTS Topology Suite. There is both a "Nearest Point" and "Closest Point" routine (I'm not sure if it is the same, or was renamed between versions) that does what you want. The result from the above is LINESTRING (205 305, 250 300), so the first point of the result is your closest point coordinates, and the length property of the ...


5

This sounds similar to "Linear Referencing" and that toolset would be available in ArcView. Additionally, you can script this tool very easily. Link to ESRI Help for Linear Referencing


4

Based on your needs, as @LouisH referred to, using Linear Referencing is definitely the way to go. I cobbled together some code that should meet your need of not hard-coding elements, but instead requesting them as parameters. As explanation, the Linear referencing tool used below takes "Routes", in your case the line features, and places "Events", in your ...


4

Solving a linear reference problem like this without importing any modules is beyond my range.. I have used Shapely(python package for manipulation and analysis of 2D geospatial geometries. And it is BSD licenced :-) ) download it from here . The 2.6 version which is the only one that supports arcgis 10 arcpy..It is a simple installation(1.5 MB size) and ...


4

I believe you can use LengthToPointCalculator transformer. But you have to do some additional preparations: Extract point coordinates to attributes with CoordinateExtractor. Merge line feature with points (FeatureMerger). You need to receive one feature for each point with line geometry and original point's coordinates in the attributes. Use ...


4

I think you should explore using Linear Referencing to display your mile markers. If you need to physically break your rivers then I think Linear Referencing will be the way to do that too.


3

Now, if the expected bus position (the planned bus route if you will) is created by using basic city GIS data (i.e. the planned bus route follows the centerlines of streets/boulevards/avenues/etc) then the delta with the actual bus location can be quite large, which would, I expect, create accuracy issues with the information the management system ...


3

Use Near (Analysis) http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//00080000001q000000.htm


3

You can use linear referencing for this. If you have your pipeline data as a line feature (which you can construct by joining all the points together if required), use linear referencing to given each weld location and M value along the pipeline. Then iterate over the points and create a new attribute (let's call it 'gap') which is the current M value ...


3

Point Connector (group by the lines Unique ID if appicable) Creates a line from the points Chopper (max vertices = 2) Chops the line into sections at the vertices 2D Length Calculator (or 3D if your line has XYZ Coords) Calculates the length of each segment... you can now query (or use a TestFilter) to identify line segments greater than x feet/meters. ...


3

When it comes to the distance along a linear feature, linear referencing is the way to go. The first step is to create routes if your feature class is not M-aware. Maybe this is already the case for you as you mentioned "route" in your question. When you have routes, you just need to use "Locate feature along route" and you have the distance to the line ...


3

I don't have enough rep to comment, but my question is whether or not the roads are already in segments that correspond to the speed zones, i.e. would each segment generally have 1 speed associated with it per side, or more than one. Regardless, here's my suggestion, though it is contingent on you having a license level that would allow a one-sided buffer ...


3

For linear route event layers, you need to create a table containing the ID of the route and the start and end m-values. If your roads don't have m-values, you can create routes using the create routes tool. The second step is to extract the m-values of your roads for each point, which can be done with locate feature along road. If I see well on your ...


3

Those ArcPy functions utilize the SgShape functions lower in the API stack. The ST_GEOMETRY object was built using some of those same functions, but doesn't expose them all (just the set that implements those required by Spatial Types and Functions implementation, which doesn't include LRS). The LRS primitive list exposed at the ArcSDE API isn't large: ...


2

I've never tried this but you might consider treating this as a reverse geocoding problem. You would do this by to creating an address locator for you rivers, treating the measure as the From and To address.


2

without looking thrugh all details in your problem, ther is one important misstake you are doing. You say that one degree is 69.17 miles. that is not right. one degree in east-west direction is different on different places. At the equator one degree is 1/360 * length of equator. at the poles one degree is zero lenght. But the longetudes are constant. I ...


2

This type of processing is achieved using linear referencing. ArcGIS has a number of tools to work with linear referenced features, however for equidistant points it is often easier to create a small script to generate the points and then join them together as new lines. In the opensource world most spatial databases have this funcitonality, as do spatial ...


2


2

http://docs.codehaus.org/display/GEOTDOC/Closest+Point+on+a+Line seems to discuss the solution to your problem. --- update by author of that page -- This page has been ported to sphinx based documentation: http://docs.geotools.org/latest/userguide/library/jts/snap.html That page just goes through how the JTS classes for snapping to a line can be used.


2

If your roads are digitized in the correct direction (the direction you need your measures to follow), you can add a new field (Type: long int, Name: From) to your road Feature Class. Then calculate the new field to the value 0 (zero) for all the features. Now, in your Create Routes tool, you choose the "Measure Source" to "TWO_FIELDS" and select the From ...


2

I would agree with BWill. Your main problem is to define the origin of each polyline. What constitutes a 'river'? Ι would make the assumption that a tributary is an standalone "route" starting from 0-> length of the tributary. Then I would the same for the main rivers, but in this case I would create a merged polyline from all the constituent polylines. I ...


2

I am not sure what is your workflow, but for interpolation of Z's between known values (all at existing vertices) I used ArcObjects IZ.InterpolateZsBetween. I've been trying to interpolate with Calibration tool previously, however this tool have a bug. I'm not sure if it fits your purpose, but see code below for IZ.InterpolateZsBetween. # import arcobjects ...


2

So after trying every possible scenario I could imagine, I finally stumbled on why the Create Routes tool was arbitrarily flipping the direction of the NHD stream segments. In the tools's online information, you can choose to either use the geometric length to obtain the routes, or custom fields you have created as one field or two field for the input of ...


2

For the types of management issues you are talking about, extremly accurate information is likely not needed. Even if the GIS system was very detailed, there is no way transit companies can affort GPS that give position to the centimeter, let alone be able to account for all the other random traffic patterns that would make a bus arrival still variable. ...


2

Given a GPS coordinate from a specific bus, and the centerline route which that bus operates along, they can simply calculate the shortest distance between the actual coordinate and the official route and essentially "place" the bus exactly on the route at that closest point in order to report "where" it is. There's nothing that I can see to be gained from ...



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