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
325 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 ...
10
votes
5answers
1k 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
6answers
3k 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 ...
7
votes
1answer
256 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
535 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
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 ...
6
votes
5answers
3k 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 ...
6
votes
2answers
121 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
484 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
145 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
2answers
1k 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 ...
6
votes
1answer
579 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 ...
6
votes
1answer
707 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 ...
5
votes
1answer
154 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
2k 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
2answers
503 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 ...
4
votes
1answer
512 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
182 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
1answer
139 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 ...
3
votes
3answers
1k 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, ...
3
votes
3answers
4k 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
594 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

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 ...
3
votes
2answers
376 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
2answers
326 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
421 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
376 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
543 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
119 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
638 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
167 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
76 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
105 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
1answer
299 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
51 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
55 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
69 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 ...
3
votes
1answer
69 views

QGIS custom labeling by clicking on polyline (and polygon)

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 ...
3
votes
2answers
66 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
171 views

Calculating the fractal dimension of a line segment

I have a shp file with hundreds of features that represent clipped segments of coastline. Each segment is made up of many vertices (dozens, perhaps even hundreds). (FYI, the segments were created by ...
3
votes
1answer
85 views

Add Z and M values to stream network produced from DEM

I created a stream network from an existing DEM. My ultimate project goal is to be able to select a river from my stream network and use the 3D analyst to generate stream profile (Elevation by ...
3
votes
1answer
462 views

Problem about converting raster to polyline and calculating total length

I have raster file of line segment. I need to convert it to line and get the distance of that line. How can i do using Python and ArcGIS 10? I have tried with GIS tools Convert Raster to Polyline but ...
3
votes
1answer
217 views

How to check if geometry is M aware?

I am trying to determine whether my shape file that I pass is in M-aware (has M value). I keep getting an error Attribute Error: 'Polyline' object has no attribute 'hasM' Not sure what I am doing ...
3
votes
0answers
138 views

How to determine longest length of segmented polylines representing rivers? [duplicate]

I have a series of shapefiles using polylines to represent the hydro network of a region. As you can see in the picture, these polylines go into great detail. These polylines are very segmented even ...
3
votes
0answers
80 views

Quantifying polyline overlap

I have a set of regions and would like to quantify the degree to which the boundary of these regions are situated on/near rivers. I have turned the regions from polygons to polylines in arcgis 10.1 ...
2
votes
4answers
365 views

How to turn all lines into one direction?

How can I turn all features of my polyline (postgis and/or shapefile) into one direction - it doesn't matter what direction. I know how to switch the direction of lines but I have no idea how to ...
2
votes
2answers
82 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 ...
2
votes
1answer
734 views

How to cut a line feature in QGIS 2.0?

I want to shorten a feature (a polyline representing a road) in QGIS 2.0. I tried the 'cut features'-tool that look like a pair of scissors. First I chose the right layer, and then clicked 'Toggle'. ...
2
votes
1answer
214 views

How to get the First and Last Point coordinates of a Polyline with Field Calculator in ArcGIS10

I'm trying to get the First Point coordinates (x,y) and Final Point coordinates (x2,y2) from a polyline in ArcGIS 10 with the Field calculator. I've added 4 (double) fields like StartX,StartY,EndX ...