Used for questions about making polyline features

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1answer
310 views

Google Maps: Decoded polylines showing up incorrectly

I'm trying to draw an encoded polyline via the Google Maps API (v3), and it seems to draw 'sort of' correctly (as in, roughly in the right area of the world ;) ) but otherwise is very, very wrong. ...
0
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0answers
12 views

Failing to get wkt to reference for a multiline

I apologize, I'm quite new to WKT (and most everything else). I have a shape that I've exported to csv. & geoJson to be loaded into CartoDB. Unfortunately, the geoJson doesn't work so I am trying ...
1
vote
1answer
61 views

Creating polyline which is average of multiple other polylines?

I am trying to use ArcGIS for Desktop to create an "average" polyline from several lines. For example if you have multiple hurricane paths and would like to plot the average position of all of the ...
1
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3answers
2k views

ArcEngine 10 Polyline with arrow

I was wondering if there is a way to draw a polyline but with an arrow head at the end point? Thanks all IPolyline line = new PolylineClass(); ...
5
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3answers
922 views

How to find line length in QGIS while editing?

I am using QGIS (before, I used ArcView). I would like to know if there is any way during the editing phase of a vector (line or polygon) to know the length of the line (total and partial) that is ...
12
votes
4answers
3k views

How to create one-sided buffers or parallel lines in PostGIS?

I'm looking for a way to create so-called one-sided buffers or parallel lines in PostGIS. Example: 1. buffer, 2. one-side, 3. both-sides I've found some discussion on the mailing list from 2009 and ...
0
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1answer
38 views

Georeferencing system of rivers using XY To Line tool? [duplicate]

I have a State Water Hydro layer from our GIS county office that does not have georeferenced attributes (It is sitting on top of a State Plane county basemap). Looking at the XY to Line tool I need ...
7
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1answer
881 views

Making radial flow map showing curved lines over short distances (20km) using ArcGIS for Desktop?

Esri have provided instructions on how to make a radial flow map but I think the curved lines will only be produced over a long distance, like half the globe. For short distances (20km) a geodetic ...
6
votes
5answers
2k 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 ...
8
votes
2answers
992 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 ...
1
vote
1answer
656 views

Polymaps + D3+ Polyline with different width and color

I am actually working on a project which involves polymaps and D3. I was wondering if you could help me on this. I have 4 locations and I would like to draw a polyline from one location to other 3 ...
3
votes
1answer
83 views

polygon from exterior points

How to convert points data to polygon, so as to form polygon from exterior point as shown above
1
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1answer
85 views

Creating new lines along specifically selected existing lines using QGIS?

I have tried to find a solution for this everywhere, with no result... My problem is that I want to be able to manually draw a line that automatically snaps to a line (creating an exact copy of the ...
8
votes
4answers
2k views

How to create arcs between two points in Python?

I've been working on an python script automating the visualization of live point data. I have a table with two coordinate pairs. I'd like to connect these two point with an arc of a circle or similar ...
13
votes
7answers
3k views

Creating trade flow maps in ArcGIS for Desktop (or any free software)?

I am trying to represent trade flows on a world map where the size and direction of arrows indicate the exports/imports of a given country. This type of map is commonly found in magazines and ...
11
votes
5answers
7k views

Convert XY points to a line?

Someone mistakenly saved a GPS track as waypoints and then sent them along to me in a .csv file. They want a line back (shapefile). What's the simplest method to convert this to a line? Available ...
0
votes
1answer
60 views

How to create coastline in Arcgis 10.2

I want to generate the shortest distance to coastlines from interested points worldwide. My question is given existing world map polygon file, what the standard way to create coastlines is. Thanks ...
9
votes
2answers
5k views

Using python in ArcGIS, create a line of varying distance from an origin point

What I'm trying to do is create a line feature from a single point, using a set distance and angle. Using ArcGIS and Python (I hope). Here's the scenario: Say I have a point at these coordinates: ...
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0answers
41 views

Need advice on creating polyline templates (polyline vs polyline ZM) for future network dataset

I am about to request large amounts of polylines from a variety of sources (municipalities). The idea is to collect bike path data and build a regional bike network (I work for the region ...
9
votes
6answers
7k views

How to join lines in QGIS?

In QGIS, I have two lines. The endpoints are near each other, but not quite aligned. I'd like to turn the two lines into one, with the two endpoints merged into midpoints. The closest I've been able ...
0
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0answers
72 views

Creating a line along an existing polyline from a point

I have a large data set of points, all of which lie on a river network and have x, y co-ordinates. I want to calculate the slope of the river channel at each point from the underlying DEM by taking ...
2
votes
4answers
266 views

How to take 2 points from One featureClass, create a line between those points, and add the line to a new featureClass (aka Shape File)?

I'm a total noob/beginner in ArcObjects. I'm coding in C#. I want to extract 2 points from a given featureClass, create a straight line between those 2 points, create a new feature class and add ...
1
vote
1answer
45 views

How to measure and mark a line or point as a template QGIS?

I'm digitizing some of our sewer assets and need to be able to measure distance and create points. So, for instance, I have a sewer main that is 65m long. I need to mark a point at the 32m mark, then ...
1
vote
1answer
314 views

ArcGIS 10.2 Extract Polyline from Start/End Coordinates

I have two files. A polyline shape file of highways and a spreadsheet that contains beginning and ending coordinates w/ descriptions of segments of the highways. For example: BegX, BegY, EndX, EndY, ...
0
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0answers
73 views

Help with building a batch model to extend radiating lines to nearest feature for multiple points

I'm new to using modelbuilder in ArcGIS 10 and was hoping I could get some help for creating a batch model to extend lines from points to the nearest feature. Here's what I need it to do: 1) ...
2
votes
2answers
121 views

How to create links between points and nearest vertex of polyline feature class?

I have a point feature class and for each point I want to find the nearest vertex on a polyline feature class. I then want to create a line between each point and it's nearest vertex on the other ...
7
votes
1answer
580 views

How to determine the longest line segment within a polygon that passes through its centroid?

A PhD student approached me recently asking how one would determine the longest straight line that passes through the centroid of a polygon, the output being a polyline rather than just a table of ...
0
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1answer
178 views

How to get polyline features from a raster file using ArcGIS 10.1?

I have a watershed accumulation file look like this: There are several white lines by visual, and I tried the raster to polyline tool and got this: Are there better ways to extract polyline ...
5
votes
2answers
123 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 ...
0
votes
1answer
46 views

Line style width property not being applied in QGIS 2.0.1

I change the line width of my style and click apply, but the property does not seem to be applying to my line data.
17
votes
3answers
3k views

How can I switch line direction in QGIS?

Something that is hopefully pretty easy. I would like to be able to swap the direction of a polyline/line in QGIS. I made a custom tool to do this in MapInfo a couple of years ago, however I can't ...
5
votes
3answers
1k views

How to create spider diagrams (hub lines) in PostGIS?

I'm rather new to PostGIS but I have done a lot of reading. One thing that I have been searching for is a function that allows users to create a "spider diagram" (also called "desire lines" or "hub ...
10
votes
3answers
1k views

Leaflet: how to draw curved lines?

So, I'm trying to draw curved lines in my application which is based on a Leaflet map. As far as I know Leaflet does not support drawing curved lines at the moment, so my question is really more ...
5
votes
2answers
6k views

How to write a script that will automatically draw lines from one point to multiple destination points? (ArcMap 9.3)

I need to create lines from an airport to numerous destination locations. The destinations change often, so drawing them manually becomes tedious. I want to create a script that will draw them ...
10
votes
2answers
1k views

How can I make a polyline wrap around the world?

I am using leaflet maps to create a representation of a round-the-world challenge. I would like to add a polyline which heads east from tokyo and then appears west of south america on the map - but ...
2
votes
2answers
256 views

minimum distance from the shore (how to retrieve the “shore vertices”)

I am student of Statistics, this is my first time using GIS., I am sorry for the stupidity of the question but I browsed online and could not find a satisfactory answer. I have some spatial data in ...
12
votes
6answers
3k views

What tools in Python are available for doing great circle distance + line creation?

I need to use Python to create a great circle distance -- both a number, and preferably some kind of 'curve' that I can use to draw in a client-side map. I don't care about the format of the curve -- ...
-3
votes
1answer
128 views

How to create a polyline feature from a point layer

I would like to create a route line based on a point layer. The existing tool does not meet the customer requirement. But using the code snippet below, the start point and end point are always the ...
2
votes
2answers
519 views

how to make a line from a set of gps points?

As a part of my research I need to create the trajectory of respondents according to the their collected GPS data (including X and Y). I am familiar with python programming, but I am a beginner in ...
1
vote
1answer
407 views

From a trajectory of GPS points to a multiline segment

Given a trajectory as a sequence of GPS points I would like to create a smooth linestring representing a path where a car drove. The data is stored in postgresql: the input trajectory in a table, ...
4
votes
2answers
257 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 ...
10
votes
5answers
3k views

How can I map a matrix of origins and destinations in QGIS?

I have a central point on a map, and I have other points in a separate layer (the location of a venue, and the origin cities of the venue visitors). Is there a plugin which would generate output ...
3
votes
1answer
197 views

How to represent Typhoon(s) wind speed using Quantum GIS / PostGIS?

I am not completly new to GIS (was taught ArcGIS at Uni) but I would still consider myself (especially compared to all these experts here) a newbie in QGIS or PostGIS. I want to display the ...
3
votes
1answer
1k views

How to create cross-sections in ArcGIS?

I have some problems to find the correct tools for a university project I am working on. Would be really nice if someone could help me to find the right tools. Is there the possibility if I have a ...
0
votes
1answer
263 views

Creating 3D lines from 3D points

Can you tell me the procedure in ArcGIS 9.3 to create 3D lines which connect the 3D points using the elevation of the points. For example, if pointA has 20 elevation and pointB has 30, then the line ...
9
votes
4answers
8k views

How to make a one part polyline from a multipart polyline?

I have a polyline which is divided into multiparts and these parts are not well ordered so that the vertex's ID are not following the polyline's plotting. This polyline is a representing a bus line ...
0
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0answers
70 views

Congressional Redistricting

I have a project coming up where I need to create new congressional district looking at only total population data. I am planning on using the census tract level of data, but I am having some ...
0
votes
1answer
63 views

How to smooth XY Co-ordinates of linear feature?

I need to smooth xy co-ordinates. see the image: In this case, i need to remove 5,6,7,8 and 9th co-ordinates or need to make those co-ordinates as a straight line between 4th and 5th. is there any ...
7
votes
2answers
289 views

How to derive vehicle paths from timestamped location data?

I've got a bunch of location data for snow plows. There's a unique id for every plow, a timestamp, and x & y coordinates. Instead of knowing where hundreds street plows were at one minute ...
7
votes
3answers
576 views

How to create transects from polygon centroid?

I have mapped potential study sites using polygons. What I want to do is create 9 125m transects spaced 75m apart. The center point of the middle transect needs to be the centroid of the polygon. Do ...