![]() (same as clicking the button in the geo-coordinates fieldset.) If the location of the postmile is different than that of the push-pin marker, a line will be drawn connecting the two markers. ![]() The geo-coordinate controls will change value to reflect the current position of the marker.Ĭlicking on the push-pin marker will determine the recognized postmile that is closest to the location of the marker, populate the postmile controls with it, and validate it This marker may be dragged with the mouse to move it to another place The push-pin icon marks the location on the map represented by the coordinates in the geo-coordinates fieldset. , and clicking on it will populate the controls for the corresponding postmile.ĭouble-clicking a postmile marker will move the push-pin marker to the postmile's geographic location (and thus populate the geo-coordinate fields with the postmile's location). In "Line" mode, if the marker represents a candidate for the first or second postmile of a line pair, the icon will show the number Ĭlicking on a postmile marker will show the information window for the postmile, and populate the postmile controls with the specification of the postmile at the marker's location. Valid postmiles are represented on the map using markers with the postmile paddle icon. R - Right (North on Soutth-to-North routes, East on West-to-East routes).L - Left (South on South-to-North routes, West on West-to-East routes).In that case a postmile suffix letter is required to indicate the side of the road to which the postmile pertains: When this happens, the postmile is determined independently for eachĭirection. Sometimes the two directions of a major route separate and follow substantially different paths. G - Reposting of duplicate postmile at route end.D - Duplicate postmile at meandering county line.If a postmile prefix letter is needed, it will be one of the following letters: If a route suffix is included, there must be a space between it and the rest of the specification. If a route suffix is needed, it will be one of the two letters: Qualifiers in a Postmile Specification Route Suffix ![]() In the Statewide Odometer, on the other hand, any change in the path of the route affects the odometer specificationįor all points downstream of the change, across the entire state. The physical postmile paddles that line the routes. This is important because of the cost to change all Takes) has minimal impact on the specifications of locations downstream of the segment that was changed. The Postmile specification uses measures that are local to each county (and Postmile Prefix codes) so that realigning a route (modifying the path that a route The Statewide Odometer measures the distance of the location alongĪ route from the beginning of the route, without regard for county boundaries. The Statewide Odometer is an alternate indicator of position within the linear reference system. Values that these qualifier codes can take, and what they mean. (In other cases, two postmiles differing in one qualifier can represent locations 10 miles apart.) For this reason careful attention to correct qualifiers is necessary. Locations along Route 84 separated by about 880 feet. For example, the two postmiles ALA 84 23.133 and ALA 84 R23.133 differ only by the presence of the "R" Postmile Prefix Code, but they represent two Whether or not a single qualifier is present. Sometimes, two postmile specifications, representing two distinct geographic locations, differ only in They must be present for the postmile specification to be valid. ![]() The Route Suffix Code, Postmile Prefix Code and Postmile Suffix Code are referred to as "qualifiers." Not all postmile specifications require their presence. The Postmile Value may be accompanied by a Postmile Prefix Code (immediately before the postmile value) and/or a Postmile Suffix Code (immediately after the postmile value). Postmile Value continues to increase as though no boundary had been crossed, and is marked by a Postmile Prefix Code of "D" - duplicate postmile at meandering county line.) (Exception: when the border between two counties meanders, so that the route crosses the same border several times, the Thus, Postmile Values reset to zero each time The Postmile Value measures the distance, in miles, from the start of the route, or from the point at which the route enters the county. The route is identified by a 1-3 digit number, and a Route Suffix Code for those routes that require one. The county is specified by its 2- or 3-letter county code (e.g., SAC for Sacramento, SB for Santa Barbara). A postmile has three principal components: a County, a Route and a Postmile Value.
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