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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4
votes
2answers
122 views

remove segments of lines in R

I have these 3 lines: line1 <- matrix(c(-1.81209, -1.80470, -1.80616, 55.68024, 55.67947, 55.67544), ncol=2) line2 <- matrix(c(-1.80468, -1.80330, -1.79690, 55.68322, ...
1
vote
1answer
156 views

3D and 2D lengths of lines in ArcGIS

I have a 2D road segment and convert it into 3D using a raster in ARCGIS 9.3. So, what i see is that the length of 3D road segment is still the same as the 2D road. How can this be? As due to ...
2
votes
1answer
162 views

How to split single lines to represent two-way streets?

I am working on a project using city road data. The data has every road in the city visualized as lines and with directional data stored in the attribute table (one-way to-from, one-way from-to, and ...
2
votes
3answers
664 views

Efficient algorithms to split and join lines?

Referring to the Figure below: How to efficiently join segments into lines? How to efficiently break lines into segments? The above will be applied million times.
2
votes
3answers
122 views

Breaking a continuous contour shapefile into smaller parts?

I created this contour shapefile and I need to break it into smaller parts so its better to manage. I also have a line shapefile of where I want the breaks. Is there a way to intersect and break them? ...
3
votes
0answers
95 views

drawing line from points [duplicate]

I have a series of XY coordinates. I want to use these points to draw a line in ARCMAP using arcobject10.1 using c#. I have saved this in a table inside geodatabase.Am i supposed to create a feature ...
0
votes
0answers
34 views

How to change value of an Line edit dynamically

I create a form in QT4 and compile with pyuic4. it create an form.py I want to modify the value of the line edit dynamiclly with code. I put this code in the form.py but never happen: ...
0
votes
1answer
90 views

Make many lines in one layer (Python)

I what to create many lines with this code: v_layer = QgsVectorLayer("LineString", "cable", "memory") pr = v_layer.dataProvider() seg = QgsFeature() ...
1
vote
1answer
469 views

Draw lines and Move the marker at the same time with KML format

it is possible to draw a line and put the Marker in the top of the line with KML format? or have i to make two KML files, it's that to say, One KML file for the Lines and another one for The Markers? ...
1
vote
1answer
730 views

PostGIS, create line from points

I have a PostGIS table with position data of numerous vehicles and want to create lines from these points. Data can be selected by vehicle id and ordered by timestamp but how to create lines from the ...
1
vote
1answer
106 views

Why won't lines from GPX simplify/generalize/smooth?

I am working with GPX data. I imported them to ArcGIS by 'GPX to feature' and then I created lines from these points. I am trying to smooth (or simplify) the lines now, but the tools 'smooth line' and ...
0
votes
1answer
533 views

How can I create a line with three points with Python in QGIS?

I'm new to Python and I'm having some dificulties. I want to create a simple layer with a line in the console of QGIS with Python. How can I do that?
-2
votes
1answer
272 views

QGIS and Python - create line with multiple points in postgis [closed]

How can I create a line, with Python functions, with many points that are records in Postgis? Thank you
1
vote
2answers
496 views

Creating a 3D line feature based on 3D point features

In ArcGIS for Desktop 10.0, is it possible to create a 3D line feature by drawing a line that connects 3D point features?
0
votes
1answer
107 views

In QGIS can I show just the lines in a Postgis query? How can I do that?

I have three tables in Postgresql, each table with one layer of lines. I want to show the path of an initial line to another final. Is it possible executing a SQL query? Thanks My three tables are ...
0
votes
1answer
381 views

Problems using v.split in SEXTANTE toolbox to split lines

I got this error: Or don't click "open output file after running algorithm", but there is no new shapefile created on my desktop. How to solve this problem and split lines at a specified distance? ...
3
votes
1answer
695 views

How to split line at a specified distance and getting coordinates of start and end points of each line segment?

I tried v.split in GRASS: and my notebook ran a lot of time but showed this error:bad allocation, then I click "OK", and got nothing. Are there other ways to split lines?and I hope to get 2 new ...
2
votes
1answer
247 views

How to Blink a line on a map similarly like a point blinking on map through lat lon points

how to blink a line on a map which is formed by lat lon points through linestring from database the points(lat,lon) comes which is stored in form of MultiLineString. similarly like how a point ...
0
votes
1answer
120 views

How to set the length of a line using openlayers

I'm trying edit a polygon by changing the length of some lines by code. Found this method to calculate based on the bearing. But I didn't find anything on how to calculate the bearing, before I start ...
3
votes
1answer
797 views

How does Flow Mapper Plugin work?

I downloaded the Flowmapper plugin for Qgis and I can't seem to find any information on how it is supposed to work... Also the text seems to cut-off and not fully showing for the input fields so I'm ...
2
votes
1answer
153 views

Shorten polylines a given distance

I have a polyline dataset with lines of different lengths. I want to shorten all polylines the same distance on both ends (e.g. 10m each side). Is there a tool or script available that could help me ...
3
votes
1answer
1k views

How do I find vector line bearing in QGIS or GRASS?

How can one extract the bearings from a set of lines in a vector file? I'm trying to find the bearings of several straight vector line segments (simplified contour lines, actually) and can't figure ...
4
votes
3answers
3k views

Convert multiple lines into single line

I've no idea if this is basic or what but I have this data that contains multiple lines (forming a polygon shape). I want to convert those lines (multiple - each with a start and end point) to a ...
1
vote
0answers
179 views

D3, Polymaps and Lines

I'm quite new to d3 and Polymaps and I have a question to ask.. I am trying to connect two points using a line, using Polymaps and d3, my starting point is from this code that Mike provided ...
1
vote
1answer
268 views

ArcObjects Java Calculate Line Length

I'm relatively new to programming and ArcObjects. I'm trying to simply calculate the length of a line (test.shp) using ArcObjects and Java. I've tried the code below with no luck. This is simple in ...
1
vote
3answers
887 views

Remove/dissolve parts in ESRI line feature class

I am using ESRI ArcGIS 10.1. I have a line which has been dissolved, having initially been composed of 4 features. I want to remove these parts, properly dissolving it into one continuous feature. I ...
4
votes
3answers
533 views

How to join number of point features into attribute of nearest line segment

I have point shapefile with lot of attributes, that represent road accidents and line shapefile with highways. What i want is to join attribute into line shapefile with value, that represent number of ...
3
votes
1answer
2k views

Spatial Join problems in ArcGIS 10.1 - intersect polygon and lines

I have hurricane tracks (Lines) and Florida county boundary (polygon) and I want to extract only those hurricane tracks that intersect Florida. In ArcMap 10.0 I used Spatial Join (from ...
1
vote
0answers
261 views

Lines as Great circles on a map

How can I get line features to appear as great circles on a map, instead of straight lines? Thanks,
1
vote
0answers
146 views

Splitting a branched river network at point layer

I need to split a country-scale river network (polyine) at certain barriers (point) so the length of (branched) river sections that have a certain minimum length. I used the following procedure: 1) ...
4
votes
1answer
231 views

How change border line to no pen with python console?

From Python console I load a shapefile with qgis.utils.iface.addVectorLayer. How I can remove border lines (change to no pen) in the active layer?
3
votes
3answers
803 views

Breaking a dynamic text line in data driven pages

I am using data driven pages and some of my dynamic text attributes are too long for my layout. Is there a way to break the line into 2 or more lines with out editing the data? Example: FROM Billy ...
2
votes
2answers
300 views

Selecting lines occupying identical positions in MapInfo or QGIS

I have two shapefiles from a client, one is their entire network (complete with unique IDs) and another a selection I need. However the selection file does not have unique IDs but the entire one does. ...
4
votes
2answers
255 views

Draw two separate lines from A to B and B to A

I have an Origin-Destination table like this Origin Destination Value A B 10 B A 100 A C 120 ... For all the locations A, B, C... I have another table indicating their location (Lat and Lon) Is ...
2
votes
1answer
189 views

Sum line length with clip intersect? [closed]

SELECT sum(st_length(st_intersection(POLY.geom, LINE.geom))) AS sum_line_length... Is this function OK to calculate the sum of lines length? Wonder if it do the clip line where one line go from one ...
2
votes
1answer
3k views

How do i calculate line segment lengths within a polygon?

I have a layer with line segments and a layer of polygons (in this case, buffers around points). I need to create a new field for each polygon that contains the total length of all line segments ...
14
votes
2answers
975 views

How can I merge/collapse nearby and parallel road lines (eg. a dual-carriageway) into one single line?

I have a shapefile from OSM which contains all the roads within a city. Larger roads (like dual-carriageways) seem to have 2 parallel lines. I'd like to collapse / combine those into 1 line so I can ...
7
votes
3answers
1k views

Elevation profile 10 km each side of a line

How can I get an elevation profile for a band of terrain? The highest elevation within 10 km (on each side of the defined line) should be taken into account. I hope my question is clear. Thank you ...
0
votes
0answers
249 views

CAD Contour Lines to ArcGIS Attributed Polylines

I'm having a 'CAD to GIS' issue. I have a dwg file which contains large number of contour lines that have been split by labels. I need to import the contour lines from CAD to GIS so that they contain ...
6
votes
2answers
537 views

How to create line with exact same length over and over again?

I need to draw 30 meter lines in specific places. Ctrl+l is too annoying to do everytime. Is there a easy way to define specific same length for a line that I need to draw many times?
6
votes
1answer
413 views

QGIS line style

I found the latest QGIS has a great tool to create complex styles, however looks like one small but very useful thing is missing, or I can't find it. I'm trying to create a line style something like ...
1
vote
0answers
313 views

Creating points along lines? [duplicate]

Possible Duplicate: How to create a point along a line given distance How to create equidistant points in QGIS? I have some road survey data and each line has an individual value and ...
3
votes
1answer
161 views

digitizing (tolerence) error in line data

I have designed a large number of boundaries. For accuracy, I took lines in patches from different data sets and merged them into one. Now I want to turn them into polygons from lines. I every second ...
11
votes
2answers
444 views

Moving points onto lines (~neighborhood)

I do have two vector layer, of which one is a point layer based on "events" by remote sensing and the second one is a line layer from local research. In my case these are earthquakes and tectonic ...
2
votes
0answers
62 views

Strange line appearing

I have this line in my project's layer which i cant make disappear: I hope you can see it. In QGIS is much more visible. An it also appears on the print composer. Any suggestions would be very ...
3
votes
0answers
111 views

Why doesn't Polygonizer copy the line ids to my polygonized shapefile?

I am trying to convert a line shapefile into a polygon shapefile using Polygonizer plugin, and when my new polygons are created all the cells in my id field are "Null", although I have clicked "copy ...
4
votes
1answer
234 views

How to extract most probable flow line from multiple lines?

I have to apply uncertainty principle to computing flow accumulation using Monte Carlo method. I generate raster with random numbers which represents mistakes in creating DEM. Then I apply those ...
3
votes
1answer
240 views

How to create a line with start and end points which are in another layer in QGIS?

In my map, there are lots of points in layer A. I want to make a line layer B and I want to make start & end points of lines snapping to points in layer A manually. Can I use points of layer A as ...
3
votes
1answer
293 views

How to connect particular sets of points with (poly)lines?

I think my problem is quite easy to be solved by the most postgis-users, but i am a bloody beginner: i have a timestamped point-table representing GPS-tracked places of different cars. To distinguish ...
1
vote
1answer
427 views

CssParameter stroke-width min max value Geoserver

I wonder if there is a minimum value for the stroke width parameter since I've a LineSymbolizer with stroke 0.1 but i want it to be thinner so i change the value to 0.05 but i dont see any difference ...