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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-1
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1answer
9 views

Converting start/end easting/northings to a single point for visualisation

I have eastings and northings for the start and end of 5m sections of the UK railway network. I want to convert these points to a central point between the start and end so I can visualise the ...
0
votes
1answer
24 views

Rasterizing a simple sloped line

I am aware how to rasterize a 2D line, but if I have two coordinate triplicates (x1,y1,z1) and (x2,y2,z2), how can I efficiently rasterize the resulting connecting line such that the raster cell ...
0
votes
0answers
31 views

Extending line by adding point at end of it using QGIS?

I'm using QGIS 2.8 to modify a line. I need to add a point on one end of this line, and then move this new point further away, leaving the original end point in the same place. I can manage to create ...
0
votes
0answers
36 views

Intersection of two lines from points with direction angles

Given two points and direction angles from each point to a third point, but no distances, how do we get the x,y coordinates of the third point? In other words, how to find the intersection point where ...
2
votes
1answer
43 views

How to interpolate line Z from sparse attribute values

I have a series of end-to-end connected 3d lines which I'd like to add elevation values for all vertices on the lines which are currently null or 0. How to accomplish this? In the following image ...
2
votes
1answer
35 views

Contour line density thinning

Would anyone know how to thin contour lines in high gradient areas such as a cliff face? Using Esri ArcGIS 10.1 with Maplex labeling engine.
3
votes
2answers
87 views

Creating polygons from line segments using PostgreSQL and PostGIS

Is there a PostGIS function that creates polygons from multiple line segments? I want to convert the pictured thirteen lines to four polygons. All lines belong to the table "boundary" (gid, geom). ...
1
vote
1answer
58 views

Giving line features of same layer different colours

I have one layer and there I have different lines. Imagine these lines are pathes of persons. So image a person x and y. And I now want to differ them by just watching on the different colours of the ...
0
votes
2answers
36 views

Connecting to lines, which are not spatially connected to each other, using FME?

I have a shape file, which contains lines. These lines are not spatially connected to each other. More specifically the end of one linestring has a slightly different coordinate from the start of the ...
1
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0answers
32 views

How to add graduated color to a line based on data?

Rookie here. I have a line that I would like to color based on some data points that I have along its path. I'm not sure the best way to go about this. Should I try to break the line up into many ...
2
votes
2answers
37 views

Assigning values of points outside a buffer to points within a buffer

I have 10m buffers around line features and a point shapefile which has some points intersecting the buffer. I would like to take each point that falls within the buffer and assign it the value of the ...
1
vote
0answers
28 views

Tool, API of or code samples for calculating spatial similarity between Lines

I am migrating a database with a road network to an other external data provider. We have joined our own data about roadworks, temporary speed-limits, etc., using ID and linear referencing on this ...
1
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0answers
27 views

Postgis - st_MakeLine and st_lineLocatePoint

Lets explain, I have 4 points (1,2,3,4), and I need to visit clients (A, B, C, D). So, I need to use st_makeline with (1,2,3,4,3)... Now I have to get % position from A,B,C,D; but in visit order. ...
1
vote
1answer
84 views

How to merge multiple overlapping lines using python?

I have a shape file with different line features, some of which overlap. Is there a way to easily merge all overlapping lines into one, new feature using python? I've seen some solutions for ...
3
votes
1answer
96 views

Intersecting lines get crossings

I have a set of lines representing bus lines. Some of the lines are overlapping and take the same roads. I am able to extract the nodes. However I am interested in extracting only crossings like ...
1
vote
1answer
53 views

How to copy a line from polygon to an other polygon QGIS 2.6.1

I have a polygon(state) now the state divide into two. I have a new polygon with two state. I want to copy only the new border(line) which divides the two state from new polygon to old. I am ...
0
votes
1answer
26 views

Where can I get the Cadinput plugin for QGIS

From Stackexchange, I got to know that Cadinput plugin could do this work. I need to create a line feature specifying the desired length and bearing in an open source GIS (Preferably QGIS) as in CAD ...
1
vote
1answer
54 views

How to create Spatial Reference System in QGIS?

I have some Attribute and the coordinate and the coordinate reference system. I want to create a DBmanagamet form my spatial data. To do that I want to create one table with name Spa_ref_sys, but I ...
0
votes
0answers
34 views

Horton Stream Order as Category for r.fixed.segmetpoints with GRASS?

I'm working with Grass GIS. I want to use v.segment to set discrete, equidistant Streampoints (starting from each mouth). Since the water network is too large, it is impossible to define the rules ...
0
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0answers
59 views

Line length for line files

Using QGIS, Brighton 2.6. Trying to calculate line-lengths for linear features (roads, trails, fenceline) and used this post (How to find line length in QGIS while editing?) and the links associated ...
2
votes
2answers
104 views

ArcGIS lines to polygons without holes

I have a dataset with contours. Depression contours are separate of the normal contours and need to be digitized counter-clockwise. Still, there are usually some faulty ones with wrong direction and ...
0
votes
2answers
63 views

Intersection between line and polygon

I have 2 layers in openlayers: first is parcel layer (polygons) and second is railway layer (lines). They are already drawn and all i need to do is when i click on some line, to get intersection of ...
1
vote
2answers
75 views

How to separate polygons within layer and measure line through each polygon?

I have 3 layers of polygons, each layer with multiple polygons spatially separated, although the layer only counts it as 1 polygon. I have a layer with a line going through these polygons. What is ...
0
votes
0answers
13 views

Creating multiple plots on long line feature using QGIS? [duplicate]

I have a very long line feature, e.g. a river and would like to plot along the length at the feature at a small scale, so it would be multiple plots. I have done this in ArcGIS for Desktop before ...
0
votes
0answers
12 views

How to equally space points in a line using QGIS? [duplicate]

How do you place points in a straight line the same distance from each other in QGIS? Thanks
1
vote
0answers
36 views

Connect two contour line with calculated line lenght

Is it possible to make plugin for qgis like PEGGER for arcview 3.2? Problem is, how to make path over contour lines with a grade in percent Formula is: K= e*100/G*M ; K=10*100/0.08*10000=1.25m K- ...
4
votes
1answer
107 views

Is there a way to split polygons by several lines in QGIS?

I have a polygon (.shp) and a line (.shp) layer. I want to split the polygon in several pieces along the lines that overlap the polygon. Afterwards I want to edit each polygon separately (attribute ...
1
vote
2answers
62 views

how can we save vector layer as a file in openlayers

Im using mapserver + openlayer for GIS API and im new to GIS. I'm done with drawing line, point and polygon features in openlayer. but not being able to save it in some shapefile afterwards i got to ...
2
votes
2answers
66 views

Create lines from polygon borders with polygons attributes

I have a shapefile of polygons that border each other perfectly, each with a numerical attriubte. I'd to create a shapefile of lines, where every line is created from the border between two polygons, ...
2
votes
0answers
115 views

How to extract elevation values at line start and end points from a DEM?

I am new to the whole gis-experience and need your help working with QGIS. I have: DEM raster with heights (3d) line-shapefile which contains the rivers (2d) I need: heights for "start" and "end" ...
1
vote
1answer
79 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 ...
3
votes
2answers
310 views

road density km/km2 calculation

I am trying to calculate the road density in my study landscape. I am using the spatial analyst, and the line density function. By default, the tool is setting a cell size of 3.6km*3.6km, and the ...
4
votes
0answers
94 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 ...
4
votes
2answers
60 views

How to extract nodes with PostGIS to a multipoint geometry

I have a line in a PostGIS table test_line. I want to extract it's nodes into a multipoint geometry. I tried the following: SELECT ST_Collect((ST_DumpPoints(the_geom)).geom) FROM test_line; But it ...
2
votes
0answers
46 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. ...
1
vote
0answers
22 views

How to delete lines that do not overlap a polygon? [duplicate]

I'am new to QGIS and I run into a problem. I have two shapefiles, one with line data and one with polygon data. I would like to remove all the lines that do not overlap the polygon. So remove all ...
1
vote
1answer
70 views

Problem Merging two line segments

I am using ArcMap 10.2 and merging several line segments with the same ID. Most of the time this works fine and I end up with one segment. (about 95% of the time) However, occasionally the segments ...
1
vote
1answer
153 views

Draw line overlays and center map

(Apologies if this is a trivial question; I'm completely new to the GIS world.) I have a dataset with start and end points of lines. Columns in the table are unique_line_id, line_start_point_lat, ...
2
votes
0answers
66 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 ...
5
votes
1answer
111 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 ...
0
votes
0answers
49 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 ...
1
vote
1answer
31 views

How to smooth lines in MapServer 5.6.8?

I have a map of property lines in MapServer and the lines look rough and have jagged edges and I wonder if there is anyway to make the lines appear smoother and more rounded in Mapserver 5.6.8? The ...
2
votes
2answers
210 views

Line Layer from Point to Point CSV file using QGIS?

My question is probably a basic QGIS question but I could not find something that would work for me. I have a file of the following format: where each from/to is a point that is already inserted ...
3
votes
1answer
90 views

Select duplicate attributes in same shape file in QGIS

I have this vector layer of lines between 2 nodes. I need to select all second entries that have the same length of the previous one. Can someone help me with this?
2
votes
1answer
46 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
2answers
83 views

Flow Mapper wrong line length calculation

I'm finding some trouble with the length calculation in the Flow Mapper plugin. As you can see in the picture below the length of the 2 lines C001-C021 = 4233.7986... C001-C009 = 6069.3053... is ...
2
votes
2answers
78 views

QGIS 2.4.0 marker line interval does not work properly when line is bending

I am trying to style a line using marker line option. When I am using styling the line in the style window everything looks nice as you can see on the print screen bellow. I am using three line ...
1
vote
1answer
197 views

QGIS PointConnector Plugin - x out of x lines not drawn

Unfortunately every try to generate lines between points (.shp) with ids (1-6) and a csv-file with from - to values failed. Maybe you can give me a hint whats wrong with my workflow? 1) I generated a ...
2
votes
2answers
187 views

Can't transform lines to polygons

I have a similar question to: How to join lines in QGIS for later using "lines to poly"? I have a line shapefile that I wish to transform into a polygon shapefile. After making some ...
3
votes
1answer
121 views

Automated removal of dangles / loose ends in line with QGIS?

Here's what I want to do: The original line is a dissolved osm extract of ways, which I want to simplify to one continous line without dangles / loose ends (red x's in picture). I found the ...