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
767 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 ...
14
votes
5answers
10k 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 ...
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 ...
9
votes
6answers
5k 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
2k 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
4answers
254 views

How to create a polygon connecting the endpoints of multiple lines using python?

I'm trying to figure out how to create a polygon that connects all the endpoints of a shapefile containing a set of polyilnes with pythonscript in ArcGIS, I'm having trouble doing this as the order of ...
8
votes
1answer
639 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
3answers
6k 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 ...
7
votes
1answer
962 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
5k 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 ...
7
votes
0answers
154 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 ...
6
votes
3answers
317 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
181 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
4answers
857 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 ...
6
votes
2answers
899 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
201 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
1k 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
5answers
1k 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 ...
5
votes
1answer
3k 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
3answers
187 views

Calculating avg distance between two non-parallet lines?

I'm currently working on creating a data model that will allow the analyst to digitize two non-parallel lines of approximately the same length. Currently the methodology is to divide the lines into 11 ...
5
votes
2answers
2k 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
55 views

Merging two polylines (street networks)

I have the following problem: I have two street datasets from completely different sources. I need some attributes from one dataset (red lines) to be joined into the other one (green lines). Until ...
5
votes
2answers
134 views

Polygon points to Polyline

I am trying to create a polyline from the points that I query from a polygon. I have a polygon, and I am getting its edges, casting them to segments, and then use QueryNormal to get the mid point ...
5
votes
1answer
260 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 ...
5
votes
1answer
271 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
4k 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 ...
5
votes
1answer
154 views

Dividing polyline layer in clusters with specific requirements in ArcGIS for Desktop?

For my work in ArcGIS 10.2 for Desktop I need to divide line layers into clusters/groups. Currently I am doing this manually, but I like to automate this. The line layers can consist of 50 up to 2500 ...
4
votes
4answers
4k 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
2k views

Merging two polylines with programming?

We are currently working on a project where we have to merge sections (polylines) to a route, but the big question is how to do this. We have currently tried adding those two as segmentcollections but ...
4
votes
1answer
102 views

Creating arrays and polylines from dictionary using ArcPy?

I have created a dictionary out of a csv values from an excel spreadsheet. I'm trying to use the keys and values in the dictionary to create arrays (one per 'Rhino') that I can use to create ...
4
votes
2answers
70 views

Modelling per-segment attributes in GML LineString

This is not a software-specific question, but rather a question about how to represent some concepts in a GML LineString. It has to be GML, for policy reasons. Consider a GML LineString consisting ...
4
votes
2answers
184 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
4answers
84 views

Create an average polyline from a set of polylines

I am trying to plot the average of several polylines (up to 40). I have several shorelines of a short section of beach plotted from different dates and would like to plot their average position. Is ...
4
votes
2answers
1k views

Create isochrones from streets with distance values?

I have made isochrone lines using GRASS and QGIS, as shown. The lines show various distances to fire stations on a street network. Now I would like to turn these lines into polygons that look like ...
4
votes
1answer
82 views

Find out if overlaying polyline matches polygon centerline in qgis

I have a polygon and a polyline and I need to find a scientific way of how close that polyline is to the actual polygon centerline. Is there any way of doing this in qgis? Any extensions, models, ...
4
votes
1answer
109 views

Clipping raster file in ArcMap over the extent of polyline shape

I have a calculated raster file, overlayed on a shapefile with lines (like on figure) I would like to clip the raster in ArcMap (since it is an interpolation and out of the vector shape it is mostly ...
4
votes
2answers
350 views

How to attribute lines with IDs of touching polygons?

I have two shapefiles: one contains streets of a city and one contains blocks (i.e. polygons bounded by the streets). I would like to have the streets attributed with the IDs of the left and right ...
4
votes
1answer
61 views

leaflet GeoJson vs polyline

Is there any real advantage in using L.GeoJson instead of Polyline when drawing paths in a map powered by Leaflet? I know that GeoJson can attach additional options. It is also possible with ...
4
votes
1answer
94 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 ...
4
votes
3answers
1k 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, ...
4
votes
1answer
753 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 ...
4
votes
1answer
860 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
46 views

Overlapping line aggregation+trim in PostGIS, while summing values

I'm sorry for the vague title, I didn't really know how to name this. I am working on a project that visualizes and simulates 17th century trade. For this project we also use so called Minard lines to ...
4
votes
1answer
170 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
745 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 ...
3
votes
5answers
1k views

“XY to Line” not converting all 58,000 records

I have a dbf (and xls) that contains ~58,000 records of latitude and longitude for both start and end points. I would like to connect each XY coordinate pair using the XY to Line tool found inside the ...
3
votes
3answers
7k 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
302 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 ...