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
656 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
8k 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
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
4answers
175 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
539 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
5k 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
899 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
4k 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
245 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
172 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
603 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
824 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
186 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
3answers
134 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
1answer
2k 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
1k 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
122 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
172 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
238 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
108 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 ...
5
votes
0answers
128 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 ...
4
votes
4answers
3k 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
2answers
162 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
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
75 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
339 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
3answers
886 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
82 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
1answer
653 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
798 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
150 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
682 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
4answers
828 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
3answers
6k 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
222 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
1k 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
575 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
42 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, ...
3
votes
1answer
99 views

Creating centerline of polygon using PostGIS?

I am aware of Finding centrelines from polygons in QGIS? but I am looking for another Open Source GIS way to do this. Is there a possibility to create centerlines in PostGIS? I have this shapefile ...
3
votes
1answer
1k views

How do I create measured line segments along existing polylines from a starting point?

I realize my problem may be solved using Linear Referencing, and if that's the case I'm looking for help figuring out the workflow involved there. I'm working in ArcGIS 10.2 Desktop Basic, and this ...