A set of ordered co-ordinates that represent the shape of geographic features too narrow to be displayed as an area at the given scale (contours, street centrelines, or streams), or linear features with no area (county boundary lines)

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4
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1answer
71 views

How to connect centroids of lines sharing the same intersection in QGIS?

I'm looking for a big help to accomplish the following task: I have this street network of the center of Turin (IT), composed by lines representing streets, and black points representing ...
3
votes
1answer
88 views

Split single line based on the 3D length

so I have a transect line which I already add the z value using the Interpolate Shape. I need to split this line into 100m in 3D length, which due to elevation must be different than 2D. However the ...
2
votes
1answer
26 views

Generating Multiple Lines from point feature to closest point features

I am doing a transportation analysis on buildings in ArcGIS 10.2. I need to find nearest point features to multiple feature classes and then generate lines to those closest point features. I was ...
2
votes
1answer
209 views

Using ST_split to split a line feature using nearby points

I have a line shapefile and a point shapefile, and the line has just one segment and its attribute table, the point shapefile has points near the line above, not on it and the close ...
1
vote
1answer
17 views

Close linestring to linering in PostGis

is there a function which closes a linestring to a linering? I couldn't found such a function in the documentation. Thanks.
1
vote
1answer
55 views

How to add dashed line in QGIS print composer

I want to display two maps in the print composer: a main one, and another showing a zoomed in section of the main map. I've drawn a rectangle over the original region and want to add two dashed lines ...
1
vote
1answer
65 views

How to make river lines intact between confluences in QGIS?

I got a river shapefile below, and I found that there are many fragmental lines in this line shapefile, like, and, Most of these are located around the confluence(node), and how can I do to ...
1
vote
1answer
64 views

Calculate 2D line of site from line layer and polygon layer using ArcGIS 10

I'm trying to run an analysis where I need to clip a radiating lines layer by land features to get the maximum distance from the central point to the nearest obstacle. What I have is a large line ...
1
vote
1answer
134 views

How to set the length of a line using openlayers

I'm trying edit a polygon by changing the length of some lines by code. Found this method to calculate based on the bearing. But I didn't find anything on how to calculate the bearing, before I start ...
0
votes
1answer
48 views

Split lines by polygons in QGIS 2.4

I have a river network (lines) and a shp with states (polygon). I would like to split the lines at the state boundaries --> split lines by polygon boundaries. Is there a geoprocessing tool to do ...
0
votes
1answer
132 views

Dashed lines do not print correct

I have a polygon with a dashed linetype; when viewed in ArcMap the linetype appears correct however when I print to pdf the linetype does not look correct. This might be a pdf quality problem however ...
0
votes
1answer
269 views

Creating distributive flow line map showing movement of passengers from bus terminal to several destinations?

I'm writing my final year B.Sc thesis on transportation (pattern of passenger flow from a bus terminal to several destinations). I intend to use a distributive flow line method of spatial movement ...
0
votes
1answer
34 views

How to do a search in a line to a specific point

I'm using QGIS 2.0.1 Dufour. I'm working with a shape file made by a single line that represents a road with 30km. In that line I want to attach pdf files containing information about some points in ...
0
votes
1answer
84 views

How to find line segment between line intersections?

Given 1 non-self-intersecting line (red) and 2 other non-self-intersecting lines (light-green), what is the best way to find the coordinates of the line in between the 2 intersections? I threw this ...
4
votes
0answers
49 views

Search Radius for Line Density

I have been working with GIS for many years but I am fairly new to the spatial analyst side of things. I am working with many satellite tracks for many different individual animals and would like to ...
3
votes
0answers
118 views

Why doesn't Polygonizer copy the line ids to my polygonized shapefile?

I am trying to convert a line shapefile into a polygon shapefile using Polygonizer plugin, and when my new polygons are created all the cells in my id field are "Null", although I have clicked "copy ...
2
votes
0answers
26 views

How do I accurately measure a gps track over a long distance?

I am measuring the length of the Continental Divide Trail that goes from the Mexican border to the Canadian border. I have a .gpx file of the entire route in NAD83 with tracks about every 50 meters. ...
2
votes
0answers
47 views

Create “mean” line from multiple lines using QGIS

I have multiple lines features (also have them in multipoints...) representing similar path (mountain trails, in this case) with various GPS precision, resulting in many lines close to each other, but ...
2
votes
0answers
98 views

In ArcMap, when using Add Surface Information, why are all avg_slope values positive?

I've got a polyline shapefile and a LIDAR elevation dataset. I've successfully used Add Surface Information (from 3D Analyst) to calculate the average slope (avg_slope) of each line segment. The ...
2
votes
0answers
232 views

Smoothing Lines in PostGIS

I want to smooth Lines in postgis, to be more specific, I want to smooth road data from OpenStreetMap. Basicly I thought of something like this scenario. This would be a possible road segment. I ...
2
votes
0answers
63 views

Strange line appearing

I have this line in my project's layer which i cant make disappear: I hope you can see it. In QGIS is much more visible. An it also appears on the print composer. Any suggestions would be very ...
1
vote
0answers
25 views

How to get attributes from line-polygon where points are snapped on, into the point-layer?

I have a SQL Server spatial table with point-objects, the points are set by snapping onto a line SQL Server spatial table. so the points are georeferenced on the line. How can I get the attributes ...
1
vote
0answers
88 views

OpenLayers, symbol every 100 pixel on line symbolizer

First: the above banner links this to How to use a sld file with Openlayers using OSM data? , but look update2. I would like to add rail-road hatching to my OpenLayers map with a Symbolizer. Example ...
1
vote
0answers
109 views

OpenLayers - Add points at vertices of line while drawing line

I would like to create points while I draw a line on my map in OpenLayers. That is, at each vertices of a line and at the end points there is a shape like a square, circle, or diamond. I have this ...
1
vote
0answers
59 views

Splitting lines once at specified distance from each end?

This is related to an old problem of mine, regarding arrowheads on lines, which doesn't look very nice unless the line is very thin. It's even an ArcGIS idea with quite a lot of votes (although no ...
1
vote
0answers
44 views

“construct points” troubleshooting

Apologies for the potential simplicity of this problem but I just cant find a solution! I need to create a series of points along a line at a specific interval. I am using ArcMap 10.2.1 and the ...
1
vote
0answers
55 views

Method for identifying upstream segments

I need to add to the attribute table of a stream network layer a column that can identify all upstream segments that contribute to the segment (for each segment). My best idea at the moment is to ...
1
vote
0answers
196 views

Splitting polyline by points using ArcGIS 10.2 for Desktop?

I have a layer containing a curved polyline and I would like to split it at multiple point locations, which I have in another layer. In ArcGIS 10.2, I can do this with the tool "Split Line at Point". ...
1
vote
0answers
100 views

Line defined by two geographical points crossing circle area with defined radius

I'm trying to calculate the amount of lines defined by two geographical points crossing a circle area defined by a center and radius. I've tried to use algorithm discussed here, but in my case it ...
1
vote
0answers
77 views

Convert polygon feature to line feature

I have a polygon shape-file i need to extract the line segments where the polygon features intersect each other and also the segment where they don't. Can we automate this process or can scripting ...
1
vote
0answers
163 views

Sources for German Standardized Symbols in QGIS

German Original: Gibt es für QGIS eine Phytonerweiterung "Planzeichenverordnung"? Zur Bearbeitung von Flächennutzungsplänen und Bebauungsplänen kommt man an den Planzeichen nicht herum. ...
1
vote
0answers
185 views

D3, Polymaps and Lines

I'm quite new to d3 and Polymaps and I have a question to ask.. I am trying to connect two points using a line, using Polymaps and d3, my starting point is from this code that Mike provided ...
1
vote
0answers
400 views

Lines as Great circles on a map

How can I get line features to appear as great circles on a map, instead of straight lines? Thanks,
1
vote
0answers
168 views

Splitting a branched river network at point layer

I need to split a country-scale river network (polyine) at certain barriers (point) so the length of (branched) river sections that have a certain minimum length. I used the following procedure: 1) ...
1
vote
0answers
296 views

ArcGIS10 Split Line at Point Failing due to Dataset size

Im having an Issue with my Split Line at Point tool. Seems to run if lucky for 700 entries before arcmap/arccatalog falls over. Debugging of the errorlog has produced nothing. The total size of the ...
0
votes
0answers
22 views

How can I draw a Line on a Shapefile?

I have a problem, in Java I can draw points on my Shapefile, but I don´t know how to draw a Line. I found the SimpleLineSymbol, but don´t know how to use it further. My first try was LineString ...
0
votes
0answers
35 views

ArcMap line shifted after export

I am working on a map with road layer. I have a dashed line as a symbol for planned highways. It is OK in the ArcMap but after the export to pdf, one of the lines is shifted. Strangely it is happening ...
0
votes
0answers
73 views

Drawing Line on existant Shapefile in Geotools

I have a shapefile that is opened and looks as such: Now I am attempting to draw a line from two points I click on that map; however the code they give for the QuickStart.java example is ...
0
votes
0answers
55 views

Use python to execute GRASS module v.distance

I have successfully use python script to import a line shapefile and a point shapefile into GRASS, and the following are their attribute table in QGIS, line shapefile point shapefile Now I want ...
0
votes
0answers
49 views

How to displace overlapping features in OpenLayers?

I have two line layers representing a different bus routes. The bus routes sometimes run through the same street. In these cases, the line layers overlap and only the upmost layer in the stack is ...
0
votes
0answers
17 views

Mapserver dynamically line

I'm a beginner for GIS especially for Web GIS that's implementation to mapsever. I created a project that I've uploaded at dedyfuadi.web.id . For the map features, I made by QGIS 2.0 and for ...
0
votes
0answers
18 views

Shorten multiline in QGIS

I have a multiline dataset in a spatialite database. How to shorten that multiline based on a specified distance or percentage in QGIS?
0
votes
0answers
44 views

How to create a point representing a polyline?

How do I convert a line (usually 2 vertices but can be more) into a single point in QGIS? I did it a couple of years ago using a build-in tool in ArcGIS 8 or 9 I think but have no idea how to do it in ...
0
votes
0answers
18 views

Point in Linefeature build through specific topology rules

i want to build Lines from Point Features following different topology rules (that lines aren't like randomly build, but how i should be following the extent from other polygons for example.. when ...
0
votes
0answers
25 views

Show the paths but not roadsides and driveways in the line layer

I want to display paths in the woods but the paths are all in One (line) layer that contains all roadsides, pavements, drivvays, but also paths, tractor road and other relevant roads in, and up to the ...
0
votes
0answers
60 views

erase a “line feature” (erase feature) from a “polygone feature”

how can I erase a "line feature" (erase feature) from a "polygone feature" (input) in ArcGIS 10? With the tool "erase" I can only use an other "polygon feature" as erase feature for a polygon ...
0
votes
0answers
22 views

grass: walking along vector line

I have a line vector which I converted into points with v.to.points. I need to get the coordinates of each point AS I WOULD WALK ON THE LINE. v.to.ascii appears to just use some other order, but I ...
0
votes
0answers
180 views

Calculating line direction in MapInfo

I have a large file of a road network. I need to calculate the value of direction (in degrees or radians) of the line segments, and save this value to a new field. I need to use MapInfo. I have ...
0
votes
0answers
36 views

How to change value of an Line edit dynamically

I create a form in QT4 and compile with pyuic4. it create an form.py I want to modify the value of the line edit dynamiclly with code. I put this code in the form.py but never happen: ...
0
votes
0answers
324 views

CAD Contour Lines to ArcGIS Attributed Polylines

I'm having a 'CAD to GIS' issue. I have a dwg file which contains large number of contour lines that have been split by labels. I need to import the contour lines from CAD to GIS so that they contain ...