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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3
votes
2answers
743 views

Extend Polyline in ArcGIS without intersecting line

I am trying to extend the ends of each line I have in a seismic survey 2 miles. I have tried using the extend line (Editor) tool but it needs an intersecting line to move to. Does anyone know how to ...
0
votes
1answer
105 views

How to find line segment between line intersections?

Given 1 non-self-intersecting line (red) and 2 other non-self-intersecting lines (light-green), what is the best way to find the coordinates of the line in between the 2 intersections? I threw this ...
4
votes
1answer
924 views

ArcMap 10.1 SP Spatial Join Problem (lines within polygon)

I have a line layer (faults) and a polygon layer (fishnet grid). The fishnet has a risk of earthquake attributed to each polygon. I want to take that risk value and give it to the fault lines which ...
2
votes
1answer
202 views

Writing an algorithm to find the most efficient line angle at which to draw lines

I've written a tool that fills a polygon in ArcMap with parallel lines at a user specified distance apart and at a user specified angle, written in vb.net and arcobjects. What i'm looking to do next ...
5
votes
2answers
266 views

Can someone clarify some details about freehand line tracing in QGIS?

I have read several tutorials and questions here on this site, but I have some lingering questions/doubts that I would like clarified. My project is tracing roadways from a 1926 map so that I can ...
1
vote
2answers
2k views

Fastest way to Join tables in python automation

My issue comes form the fact that doing Joins manually is actually relatively quick (5mins), but python automation of this process is 6hrs! Here is my code: import arcpy GDB_MARK_TO_MARK_VECTOR_VIEW ...
1
vote
1answer
2k views

Geoserver SLD Line styling with external graphic instead of WellKnownName

I have problem with styling in geoserver. Using tutorial from http://docs.geoserver.org/stable/en/user/styling/sld-cookbook/lines.html#id7 everything is ok but when I want to use ExternalGraphic ...
3
votes
1answer
144 views

Tornado Data Points: Linking 2 Points in QGIS on the Same Row

So I've got these tornado .csv files that have two latitude & longitude entries with the left-most in the table being the beginning point and the right-most being the ending point of the tornado, ...
0
votes
1answer
41 views

How to make XY to Line dynamic to access query?

I have connected the Access file to the ArcGIS file, and displayed it using the tool XY to line, but when I change the access file, this is not automatically adjusted in the ArcGIS template. Somehow, ...
1
vote
0answers
125 views

Line defined by two geographical points crossing circle area with defined radius

I'm trying to calculate the amount of lines defined by two geographical points crossing a circle area defined by a center and radius. I've tried to use algorithm discussed here, but in my case it ...
1
vote
2answers
263 views

How to extract common outline of multiple polygons with code?

I'm not really asking for a chunk of code to do this, but more of an algorithm I can work with myself. For example, this is the state of Maine, obviously, and I have the points of each county ...
1
vote
1answer
178 views

QGIS how to compute a trendline of two point lines? [closed]

Does anyone know how to compute a trendline for two lines of points? I have two lines of points of a 10 km long urban road. 1st line is one driving direction and the 2nd line of points ist the other ...
3
votes
3answers
922 views

How to draw (or add) a line indicating a specific latitude/longitude?

I'm trying to add a single line that show a specific latitude (e.g. the Tropic of Cancer) I don't want a gird but only a single line even in a vector layer.How can I do that I've try with pyQGIS ...
2
votes
1answer
39 views

Get coodinates from point shapefile

I converted a line shapefile to points as you can see in the attached image. Is there a way to know the coordinates of each point? Any help would be really appreciated! PD Im using QGIS 1.8.0
1
vote
0answers
127 views

Line features into polygon features

Can any one tell me how to convert line features into polygon features in ArcGIS. I am using ArcGIS 10. I searched the arc toolbox for any tools for this conversion, but I couldn't find any. Please ...
3
votes
2answers
830 views

Get coordinate of second to last vertex for python ArcGIS

I need to obtain the x and y attributes of the second to last vertex for each segment and add to the attribute table using Arcpy (or some other python module). To get the Y co-orodinate of the first ...
5
votes
1answer
1k views

How can I add an arrow to a line?

I want to have arrow heads at the end of a number of lines. I add these through Line properties --> Line decorations. It looks nice and all when displayed in the legend: But in my map, due to ...
3
votes
1answer
202 views

How can I move along a line (or path)?

Given a line (street, railroad, river...) I want to simulate a moviment inside this line. Example: See this picture: Say I'm in "Nagqu" and want to move to "Kunlunqial". In a time (t=0) I'm in ...
2
votes
1answer
117 views

How to make marker line thicker in QGIS?

I'm mapping railways, find that the usual cross marker line is so thin it doesn't show up in Print Composer at web resolution, and can't find any way of making it thicker, only the main line. Is there ...
2
votes
0answers
377 views

Smoothing Lines in PostGIS

I want to smooth Lines in postgis, to be more specific, I want to smooth road data from OpenStreetMap. Basicly I thought of something like this scenario. This would be a possible road segment. I ...
2
votes
2answers
174 views

Convert point file to polyline but not joining every set of points in ArcGIS10

I have a dataset that looks like : OBJECTID Shape KP DESCRIPTION EASTING NORTHING 1 Point 0.04 Span;Start 525112.2 6728715.4 2 Point 0.0506 Span;End ...
0
votes
1answer
156 views

How to draw downhill path with TileMill and KML?

I have a kml file which contains downhill paths and other points. Here is an example. I imported the file to TileMill and I used Save & Style, but nothing appeared except a few points. I think ...
2
votes
1answer
204 views

Line calculation from KML file

I am a beginner in QGIS 2 and Mac OSx Mountain Lion I need to get line length in meters for different gps waypoints. 1 I import kml file to create a new vector shape (this works fine). The projection ...
6
votes
3answers
2k views

A tool or way to Extend line by specified distance?

I have a purely aesthetic layer which has arrow symbols. Some aren't showing up right because the line is too small. I have selected maybe 50 records where I need to extend this line by a given number ...
0
votes
0answers
330 views

Calculating line direction in MapInfo

I have a large file of a road network. I need to calculate the value of direction (in degrees or radians) of the line segments, and save this value to a new field. I need to use MapInfo. I have ...
1
vote
1answer
230 views

How to discretise a line into grid lines

Having a line and a grid, the aim is to discretise the line into grid lines. In the following figure, the given line is in black, its intersections with grid lines are blue, the desired is set of ...
2
votes
1answer
120 views

Draw a line and a buffer around it onto the spheroid

I need to draw a line between two points and create a buffer around this line. The only difficulty is that I need to draw not a "cartesian" line but a line that is laying on the spheroid. I tried to ...
2
votes
1answer
212 views

Split polygon into lines

I have a polygon layer which looks like this . I used the QGIS multiparts to singleparts tool and also polygon to lines. In both cases i got this type of result . I want to extract polygon into ...
1
vote
0answers
95 views

Convert polygon feature to line feature

I have a polygon shape-file i need to extract the line segments where the polygon features intersect each other and also the segment where they don't. Can we automate this process or can scripting ...
1
vote
1answer
198 views

How to get a centroid of a closed line in MYSQL

I have a table that contains only closed lines (lines where endpoint is the same as startpoint). I would need to find a centroid for those lines. How would I be able to achieve it? It does not ...
3
votes
1answer
191 views

How to convert a line to points?

I'm working with QGIS and I want to convert a line into many points, does someone know how? Thanks.
1
vote
0answers
214 views

Sources for German Standardized Symbols in QGIS

German Original: Gibt es für QGIS eine Phytonerweiterung "Planzeichenverordnung"? Zur Bearbeitung von Flächennutzungsplänen und Bebauungsplänen kommt man an den Planzeichen nicht herum. ...
3
votes
1answer
511 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
334 views

extend line to feature. programatically

Thanks in advance for any help. I'm trying to programmatically extend hundreds of lines (blue in image) to a single polyline feature (red in image). Sometimes the lines intersect each other, but I'd ...
3
votes
1answer
154 views

How do I make line symbols intersect cleanly without showing edges in QGIS?

I digitised a map showing electric grid lines. I merged a number of lines into a single feature. Now, I'd like these lines to be displayed so that the intersections appear continuous. At the moment, ...
1
vote
2answers
728 views

Qgis - need to draw exact lines (mtrs) with fixed angle

I use GIS 1.8. I have the need to be able to draw exact lines and shapes on a bing map. (This is to project a yet to be build greenhous project on a map to show what i would look like). I have ...
0
votes
1answer
340 views

Update Point ID as Start Node and End Node to Line through FME

I need your help to perform the below process in FME. I have two layers: Pole Data (Point) and Cable (Line). Cable has no ID. I want to keep the Cable which is going through the Pole. Then make the ...
0
votes
1answer
195 views

interpolate point values to line

This might be a stupid question and I apologize if so. I have count data for different trails. They are points and I would like to make an average of those counts for each trail so that each trail has ...
1
vote
1answer
287 views

QGIS offset dash line style - dash spacing does not vary with rotation

I'd like to make a USGS-style dirt road marker but with smaller dashes and bigger spacings (i.e. less duty cycle) to indicate lower quality road. First attempt = two simple lines, custom dashes of ...
0
votes
2answers
277 views

Updating a column with line direction in MapInfo

I was wondering if there is a way to update a column in MapInfo with the digitised line direction. I have two TAB files, one is complete lines and the other is sections of the same lines (both have a ...
1
vote
1answer
152 views

Remove parts of line that fall within a polygon

I have a polygon and two lines. How can I remove the portion of each line that falls within the polygon? # polygon coords <- matrix(c(-1.798123, -1.793072, -1.805767, -1.804129, -1.798123, ...
4
votes
2answers
195 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
344 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
208 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 ...
3
votes
3answers
1k 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
181 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
100 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
41 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
95 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
792 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? ...