A digital map feature that represents a place or thing that has length but not area at a given scale. A polyline feature may have one or more parts.

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15
votes
3answers
474 views

Zigzag Line Symbol in QGIS

I'm looking for a zigzag line symbol in QGIS. Is there perhaps an easy way to do this that I'm missing? I have tried creating a marker line using a simple triangle marker (^) and adjusting the size of ...
11
votes
5answers
2k views

Measuring straightness of a curve segment (represented as a polyline)

I'm working on an automatic elevation contour labeling algorithm and one of the factors that I want to take into account when deciding the positions of labels is how "straight" a particular segment of ...
8
votes
5answers
5k views

How to create points in a specified distance along the line in QGIS?

I want to use QGIS creating points along the line, but in specified distance. I found two GRASS tools in SEXTANTE Toolbox: v.to.points v.segment I tried v.to.points, setting the maximum distance ...
8
votes
6answers
4k views

Get a point on a polyline from end points given distance along poly line

I have start point and end point of a polyline. How can I get a point on that polyline from end points specified by the given distance. How can I get this by using arcpy provided that this script ...
8
votes
2answers
1k views

How can I create random points along a polyline in QGIS?

I am trying to create random points along a polyline shapefile in QGIS. Basically, like the 'random points' tool in 'research tools' but for polylines instead of polygons. I have tried converting ...
8
votes
1answer
361 views

How can I transform polylines into points every n metres in PostGIS?

Question in pretty much the same as this, but I need to use PostGIS. I have a number of polylines, and want to trasform them into points every n metres along these lines. edit: Thanks a lot to ...
7
votes
1answer
719 views

How to create arrows lines automatically on ArcGIS, for a thematic map of directed flux?

I need to create a map with the Import and Export Flux between countries. I have the needed data in my table. But I wish to know if there is any tool or extension which will allow me to create those ...
7
votes
2answers
2k views

QGIS or Postgis - How to split polylines with a point layer?

In QGIS, I would like to split the polylines in a layer loaded in the workspace with the points in another loaded layer. If a point intersects a polyline, this polyline should be transformed into two ...
7
votes
4answers
3k views

How to close multipart polyline gaps in ArcMap

I have a multiple multipart contour lines that originally came from CAD drawing. I converted these into a polyline shapefile in ArcGIS. The issue I have is with gap in each contour lines that are ...
7
votes
4answers
1k views

Splitting polylines according to coincident (or touching) points with other polylines?

The question is unfortunately not answered yet. I'm looking for a method or python script to split polylines according to coincident points with other polylines, but avoid splitting the ones which ...
6
votes
3answers
122 views

Waypoints with coordinates in R

I have a SpatialLineDataFrame with 20 observations of 4 variables (in WGS84). I want to create waypoints every 10 meters. Every waypoint will has the x y coordinates. I tried to do it manually like: ...
6
votes
2answers
142 views

Finding lines in point patterns?

I have a point pattern (see below) in which I assume to find "significant" lines of points. However, I did not find any method that is integrated in a GIS or in R that searches for such line pattern ...
6
votes
2answers
678 views

How to calculate tortuosity of a coastline?

I would like to calculate the tortuosity (or fractal dimension) of a coastline within a 1km buffer surrounding a point on that coastline. I have hundreds of points and therefore need a tool or scripts ...
6
votes
1answer
167 views

Split polylines in ramps

I have a shapefile (polylines) of some roads and I want to divide the roads in ramps. Ramp = a piece of the road delimited by the top of a hill and a valley. So, pretending that you're driving in ...
6
votes
1answer
800 views

ArcGIS Symbology Transparency

Using ArcGIS 10.1, I am interested in symbolizing a series of polylines to generate a pseudo-heatmap like one of the answers to this question. The essence of the solution idea is to symbolize each ...
5
votes
4answers
279 views

How to Unsplit/Dissolve multiple touching lines in Stream Network?

I am trying to dissolve multiple lines for stream networks into individual features. The dataset contains many stream networks so a complete dissolve of the whole dataset wont do as I would like to ...
5
votes
2answers
3k views

Extract Raster from Raster using Polygon shapefile in R

I am new to R and using the raster package. I have a problem extracting polygons from an existing raster file. If I use extract(raster, poly_shape) function on the raster it always creates a list ...
5
votes
1answer
816 views

What units are shape_length in?

When generating polylines from a series of points, I used "Points to Line" tool. From this, Arc generates a polyline feature class, which includes the attribute shape_length. What units are these ...
5
votes
2answers
894 views

How to draw lines from two points in a CSV?

I have a CSV file where one line looks like this: Duration, user, lat-start, long-start, lat-end, long-end 298, Casual,38.9101,-77.0444,38.91554,-77.03818 Each row in the CSV has two points and I ...
5
votes
1answer
179 views

Shapefile and DEM: check rivers behaviour

I'm working with shapefiles representing rivers (rivers.shp), and DEM for the terrain elevation (terrain.tif). Basically, I want to check that my rivers (stored as polylines in my shapefile) behave ...
5
votes
2answers
3k views

Leaflet Polyline with custom fill pattern

I'm drawing Lines with leaflet.js an have to create custom styled polylines. So i got various image files which should be like a repeated background image in HTML. So is it possible to give a drawn ...
4
votes
4answers
2k views

Calculating X and Y of line start and line end using ArcPy?

I have a series of polyline shapefiles and I am trying to automate the process of calculating the X and Y coordinates of the line start and line end using Python. I have added the 4 fields (startx, ...
4
votes
2answers
135 views

Is it possible to position QGIS labels by clicking on polylines (and polygons)?

QGIS has now few really good options for custom labels but I can't find a way how to easily manage labels along polylines. Is there a tool which helps me place labels by clicking on a polyline so the ...
4
votes
1answer
84 views

Calculate distance from all points to all lines within 10km using FME?

I have a polyline shapefile and a point shapefile. The points are along the polylines. There are over 100 lines and over 10,000 points. I want to calculate the perpendicular distance from every ...
4
votes
1answer
663 views

How to repair and clean contours from high data resolution (lidar)?

I'm unsuccessfully trying to make a bathymetric map with contours extracted from Lidar data at 1 m resolution. The extracted contours have a lot of artifacts like dangles and islands. First I used ...
4
votes
1answer
105 views

Measuring Sinuosity of Walking Paths

I'm currently working on a project that examines the movement of consumers through different kinds of retail spaces in Central Asia – namely, bazaars versus supermarkets. I've equipped dozens of ...
4
votes
1answer
392 views

Calculating “travelled distance” of a GPS track without including “stops”

I have a set of GPS tracks from a cycling event and I want to correlate their distance along the route. Problem is: when a rider stops, generally by entering a covered place, GPS keeps logging (low ...
4
votes
0answers
79 views

Cumulative length of polylines

I have a polyline shapefile with streams. I would like to turn this to a raster where there would be a cumulative length sum value in each pixel moving downstream. In other words, this would be an ...
3
votes
3answers
5k views

Polyline length calculation in ArcGIS 10/VB script

I used to run this length calc on my data in ArcGIS 8 and 9, and now it don't work in ArcGIS10. Can you tell me what I have done wrong? Dim dbllength as double Dim pcurve as icurve Set Pcurve = ...
3
votes
4answers
356 views

Convert line shapefile to raster, value=total length of lines within cell

I have a line shapefile representing a road network. I wish to rasterize this data, with the resulting values in the raster showing the total length of the lines that fall within the raster cell. The ...
3
votes
4answers
121 views

Workflow for identifying gaps in polyline shapefile

So I have a polyline shapefile showing the border of a city, however there are multiple gaps in the shapefile ranging from ~2m to well over 1km that are almost impossible to see when viewing the area ...
3
votes
4answers
843 views

ArcObjects C#: select intersecting polylines

My questions seems trivial but it is a real blocker for me. So please help!!! How can I, using ArcObjects with C#, select only those polylines in one layer that intersect with each other? It sounds ...
3
votes
2answers
1k views

Calculating the distance between points and multiple lines?

I have a point shapefile of about 100 points and a polyline shapefile of about 200 lines and I am interested in finding the distance between every point and each individual polyline. My polyline ...
3
votes
2answers
461 views

How to add point to a polyline?

I have a polyline, and i want to add point (vertex) on a specific distance, like two meters for example. How can i do that?
3
votes
1answer
69 views

Union on lines using ArcPy?

Essentially I want to union multiple (20) congruent line shapefiles, where overlapping line segments in the input shapefiles are combined into a single resulting output shapefile. But I can't union ...
3
votes
3answers
512 views

Create voronoi diagram from line segments

I'm looking for a way to create a voronoi diagram based on line segments instead of points. See the example below (taken from this presentation). Ideally I'd like something I can script from Python, ...
3
votes
2answers
514 views

Line start and end nodes: determining what is a junction

I have a layer of points and polylines and want to determine which points are road junctions. I currently have all start and end nodes within 3m of my road network as a layer. However I cannot ...
3
votes
1answer
655 views

How to join 2D polylines and DEM into 3D polylines?

I got a simple question but could not find a satisfactory answer yet: I have a road network in 2D/PostGIS and a DEM. I want to turn the road network into 3D by retrieving the Z-value from the DEM. ...
3
votes
1answer
631 views

How do I find the intersection of two polylines in PostGIS?

I have a set of road conditions reported for small segments of road, and I am hoping to determine the specific subset of each segment which intersect with a route along the road so that I can draw the ...
3
votes
1answer
649 views

Pivot a polyline at vertex or distance using ArcObjects C#

I hope you can help me with that one. I'm using ArcObjects with C# trying to rotate only one part of a polyline at a vertex or distance along the polyline. The polyline is zAware and has values at ...
3
votes
3answers
130 views

Automated way to join

I have river networks (polyline) of several adjacent countries as shapefiles that almost match up at the borders, but not quite. Is there any way to automatically connect them to a consecutive river ...
3
votes
2answers
189 views

Polyline in shapefile

I'm still pretty new to arcpy and am still learning. I'm working on a script that has a polyline as its input. I'm able to traverse the polyline and get points at certain intervals. These intervals ...
3
votes
1answer
121 views

Representing overlapping polylines in QGIS

I have several shapefiles representing bus lines with different colors for each segment, however, because the lines are exactly superposed, only the shapefile on top can be seen. Is there a way to ...
3
votes
1answer
237 views

QGIS - Calculate distance between a point layer to n nearest polylines

In QGIS I am trying to calculate the distance from a point layer to a polyline layer for the n nearest polylines. I have figured out how to calculate this distance to the centroid of the polylines ...
3
votes
1answer
341 views

Cut polyline in Qgis 2.4

I want to shorten a feature (a polyline representing a road) in QGIS 2.4 In QGIS 2.0 there was "Split Features" tool in the "Advanced Digitizing" toolbar. Here the icon: I'm not able to do this ...
3
votes
2answers
157 views

QGIS Line End Caps

When styling a road network where all sections of the network between junctions are separate paths, I style the ends of the lines to rounded to remove any gaps that might appear where the joins are at ...
3
votes
1answer
482 views

What's the unit of measurements produced by “sum line lengths”?

My goal is to find the total length of roads per county for a particular state. You would think there would be a simple government spreadsheet with this information in it.... I cannot figure out how ...
3
votes
1answer
64 views

How can I find small distance between polylines?

I`m trying to find lines which have small distance between them and I am using ArcGIS 10 for this. I had tried to make points at the both ends of the lines and to detect the distance between points ...
3
votes
2answers
78 views

How to automate drawing a polyline from 2 intersecting datasets based on proximity?

I've been stuck on a situation recently where my company's data has to be integrated with another. Basically there are two point shapefiles comprising of >50000 points, and as shown in the image ...
3
votes
3answers
96 views

Take parallel lines and automatically move them apart

Rather than collapsing parallel lines, I am looking for a process that would separate them. There are a number of lines on the network that run too close together to distinguish as separate ...