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13

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 ...


11

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: ...


6

You should convert layer 1 from a feature class into an event table and then use the Overlay Route Events tool with the Union option. That preserves all events and attributes that exist from both event tables into a new event table where every unique closest pair of measure positions creates a new line segment. See this discussion of the Overlay Route ...


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


5

You could try something like this: for the scenario shown above, the script below import arcpy roads1 = #path to roads layer 1 roads2 = #path to roads layer 2 r1 = [row for row in arcpy.da.SearchCursor(roads1,["SHAPE@","NAME"])] #add field to hold required string arcpy.AddField_management(roads2,"COMMENTS","TEXT") with ...


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.


4

As far as I know, it's still the case that you cannot use the M-part of geometries. I know that PostGIS supports M and it depends on your use case if that can be an alternative.


4

The northern two-thirds of Georgia should be pretty good, because the South Carolina coordinate reference system is Lambert conformal conic-based. Thus, the standard parallels extend through Georgia too. I ran a point at 31N 85W through the National Geodetic Survey's SPC program to see what the distortion would be. Note: South Carolina's zone is 3900. It ...


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

Or... You can think of M being any kind of variable for a given location, like temperature, time,... which isn't directly interpreted as a location.


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: ...


3

The ST_Split PostGIS function is probably what you want. To get a single line split by multiple points, you could use something like this multipoint wrapper plpgsql function. I've simplified it just to the "split (multi)lines with (multi)points" case below: DROP FUNCTION IF EXISTS split_line_multipoint(input_geom geometry, blade geometry); CREATE FUNCTION ...


3

Rachel: First you need to convert the lines to LR Routes with assigned measures. Each line should have a Field with a unique ID value of some kind that means something to you. That field will be used as the Route ID. If the lines have to start at 0 for both ends, depending on the camera referenced as the start then you should make the Route ID something ...


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 ...



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