The distance-independent relationship between two points in space that specifies the angular position of either with respect to the other

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16
votes
2answers
4k views

How can I calculate the bearing between two points in PostGIS?

How can I find the bearing between two points in PostGIS? Please specify in your answer whether or not the method producing a bearing on the spheroid, or a planar bearing.
11
votes
2answers
302 views

Which weather on my road? Looking for a spatial weather forecast web service

My friend Bob goes from A to B leaving tomorrow morning at 6:00. There are many direction services that indicates him short, fast and/or cheap routes. Bob does not like to drive under the rain and ...
8
votes
1answer
1k views

What determines “west” in Antarctica?

Hopefully this isn't so far afield as to get banned - apologies in advance to those who think it doesn't belong. This article discusses a region of Antarctica which is described as "West Antarctica". ...
6
votes
2answers
265 views

Create a projection to emphasize a given direction in ArcMap?

Suppose one had a dataset (centered on a given coordinate) of lines that were very close together in terms of longitude but also had important turns/bends far separated by latitude. In order to map ...
6
votes
1answer
1k views

How do I find least cost path over a DEM based on slope magnitude and direction?

What sort of algorithms can I use to find a least cost path through a DEM where it costs more to traverse a cell going downhill or uphill than it does to follow the contour of the land? All the ...
5
votes
2answers
8k views

Showing polyline direction in ArcGIS for Desktop (ArcMap)?

How can I show the direction of a polyline as it was digitised? I need this to check if my network analysis is obeying one way streets. I know of a tool in Xtools that can do this but my trial ...
5
votes
0answers
184 views

Advanced GMaps directions

I try to create an application for taxis. The application will be GMap based. On the map will be marked the region in which the taxi driver is working in. The region will be a polygon designed by ...
4
votes
1answer
703 views

Understanding percentage drop-raster (flow direction-tool)

I'm creating a Topographic Wetness Index using a python script (http://arcscripts.esri.com/details.asp?dbid=16750) As I don't want this just to be a blackbox, I'm trying to understand the different ...
3
votes
1answer
52 views

Change direction of polylines from DEM data

I am trying to define the direction of my polylines (which represent gutters in a drainage system). Does anyone know if it is possible to define the direction based on elevation data extracted from a ...
3
votes
1answer
2k views

ArcMap - Display direction of points

I imported a few geotagged images and created a points shape showing their locations (or more accurately, the location of the camera) with the "Geotagged Photos to Points" tools. The attribute table ...
3
votes
1answer
720 views

How to get the Flow or directional raster map using GRASS?

Aside from using r.fill.dir in GRASS, is this the script to produce the Flow or directional raster map? Is the output for the script the following graphic? http://grass.fbk.eu/grass63/screenshots/...
3
votes
1answer
145 views

Getting the compass point given longitude, latitude and direction in degrees

I have this data gathered using a GPS device No. Time Longitude Latitude Speed(Km/h) Compass point Direction (deg) 1 10/20/15 1:34 40.11724 -3.21032 11 Northwest ...
3
votes
1answer
175 views

Problem with flow lines in ArcMap

As a part of my PhD I have to map the rivers of Northern Peloponnese, Greece. I have downloaded two DEMs from Nasa Reverb, which I connected with "mosaic to new raster". I have started the usual ...
3
votes
1answer
89 views

How to display bidirectional flows?

I'm working on a map showing oil shipping. Basically, I have a a series of nodes/line segments that make up the shipping network. I've joined the sums of oil that traveled along each node, so can ...
3
votes
2answers
125 views

How to deal with Roundabouts in PgRouting

Can anybody guide me to to deal with roundabouts in pgrouting?? I have some roundabouts in my road network and when i try to make route from one point to another, it gives me wrong direction where it ...
3
votes
2answers
2k views

How to display arrows on pipes from upstream to downstream using QGIS?

I am trying to display arrows on pipes of a sewer network so their direction is from upstream to downstream edges of the pipes. I have managed to display those arrows on a polyline layer (which is ...
3
votes
1answer
939 views

Driving directions and multi-modal route planning service for a city with OpenStreetMap data

First off I'd like to mention that I've never come close to anything-GIS until a few weeks ago when I thought of this. So please expect some layman's questions. I'm looking to create driving ...
3
votes
1answer
405 views

Is there an open source directions webclient for pgRouting like the directions API from Google?

I am looking for an open source webclient with (Google) directions functionality (like draggable lines to create extra waypoints) based on an pgrouting database (with an osm2pgrouting topology). I ...
3
votes
3answers
412 views

Identifying the side of a point from the closest polyline in ArcMap 10.0

I have a set of polylines (a network of streams and rivers) with information on the left and right side of the streams on riparian structure. I also have locations (points) of either side of the lines....
2
votes
2answers
100 views

Query Features in Certain Direction

I have a polyline that I would like to query features that are on it's left, right, top, bottom. I am not looking for the features surrounding it but for features that are on a certain location from ...
2
votes
2answers
657 views

how feasible is building my own map server? providing GeoCoding, Directions and Navigation

My need is a heavy use of routing. same as Google's Directions API. I'm looking for a viable alternative to abusing google and paying them too much. how difficult is it to have my own server for that ...
2
votes
2answers
208 views

ArcGIS lines to polygons without holes

I have a dataset with contours. Depression contours are separate of the normal contours and need to be digitized counter-clockwise. Still, there are usually some faulty ones with wrong direction and ...
2
votes
1answer
377 views

Showing directional line symbol in ArcGIS for Desktop?

Is this possible in ArcGIS to have variable number of arrows on the line to show direction? This is an ArcGIS example, where I can have fixed (1,2,3,4,5...) number of arrows and it stays the same ...
2
votes
1answer
44 views

Distance to coast in specific direction

I have a point layer and want to know the distance to the coastline (line or polygon layer) from each point in a series of directions (0, 10, 20, 30 degrees, etc). I have found this python script (...
2
votes
2answers
43 views

postgis How can I obtain directional buffer?

I have a geometry (polygon) which I want to extend with a buffer while testing on it in a where clause. The problem is that I would like the buffer to be only applied according to one or more ...
2
votes
1answer
171 views

Draw line with lon, lat, distance and azimuth

I have table in PostGIS with lon, lat, distance and azimuth columns. I want to make Geoserver draw a line through first point with given length and direction. I can turn lon and lat to geometry in ...
2
votes
1answer
94 views

Direction of movement with points2paths in QGIS

I have a data set containing ship movements. I used the Points2paths plugin in QGIS to connect the points with the ship's names as factor and the time the signal was picked up as sorting value. Now I ...
2
votes
2answers
226 views

Working out parcel direction

I am looking at applying a direction indicator to land parcels and houses (in MasterMap). effectively, I am looking at applying a direction indicator to the land and the buildings associated to the ...
2
votes
1answer
119 views

Euclidean direction

i'm trying to calculate the euclidean direction, in ArcGIS its very easy using the Euclidean Direction tool of Spatial Analyst but in QGIS i don't find how to do it. Any tips for this in free ...
2
votes
1answer
73 views

How to detect other objects are on which side of an object based on lat long

I am working on a system that detects the lat/long of vehicles. I want to track other vehicle's position: left, top-left, right, top-right, bottom-right, bottom-left etc based on lat/long. I have ...
2
votes
0answers
66 views

Why this pyqgis code cause crash dump in QGIS?

In ArcGIS there is gp.EucDirection to calculate Euclidean allocation, distance, and direction around a point, Is there equivalent function in pyqgis or gdal? I wrote a script with help of gene and ...
2
votes
0answers
116 views

Finding number of left and right turns for each shortest route

I have a network dataset for a city. I have, lets say, 200 trips that are made in that city. I constructed the shortest route for the every pair of the trips, and also the actual route travelled by ...
2
votes
1answer
359 views

Knowing acceleration, gyro and compass data how to calculate north direction [closed]

I have a small video camera with an attached sensor. I can get from the sensor his acceleration, gyro and compass data. Knowing this data I need to rotate the camera so that it will look strictly ...
1
vote
1answer
303 views

How can I create individual directional point symbols in MapInfo?

I have a point tab file where one of the attributes is a 0-360 direction. I want to create an arrow symbol for each point with the arrow pointing in the direction listed for that point in the table. ...
1
vote
3answers
308 views

Collecting direction of taken photo in ArcGIS for Collector?

Just wanted to know if it is possible to collect the direction of taken photo in Collector ? Obviously, I would like to know which direction i'm facing (North, east south, west) when taking the photo. ...
1
vote
1answer
20 views

Representing directional data from an attribute field

I have a table in ArcMap 10.2 containing strike measurements, in degrees, for ~100 sample sites. Each measurement has a UTM tied to it, and the map has already been populated with points, but I would ...
1
vote
1answer
81 views

Using Copy Traversed Features to count turns for a route result in Network Analyst

I have the output of the route layer. And I want to determine the number of right and left turns for each route. For that, I used the COPY TRAVERSED ROUTE FEATURES tool from Network Analyst. However, ...
1
vote
1answer
298 views

Calculating field length in certain directions (raster)

Currently I'm working on winderosion. For my purpose I like to calculate the length of agricultural fields in certain wind direction. I would like to do it for raster. To be more precise: I have ...
1
vote
2answers
240 views

How to convert Direction Of Travel OSM vectors from a “system” to another?

I have a painful doubt according Direction of Travel (DOT) vectors in OSM data. I'm using ArcGIS10, and a OSM data shapefile. I have a OSM road layer, that has many "Both ways" vectors and many "One ...
1
vote
1answer
146 views

Distance-direction computation of lines with exactly/more than two nodes?

A distance and direction tutorial provided as an Answer at How to add Direction and Distance to attribute table? uses: xat (0 ), xat (-1 ) and yat (0 ), yat (-1) for start and end points of lines; ...
1
vote
1answer
84 views

Color gradients to show direction in polylines

I am referring to this very useful hack to change the color gradient of buffered polygons in order to show direction (with a gradient from red to green, for example) hack The only problem is that ...
1
vote
1answer
113 views

How to show directions on the map?

I am using Mapbox, Leaflet. Via Mapbox Walking directions I create directions and save origin and destination markers coordinates; Then I want to show this created direction. So I do following: <...
1
vote
1answer
310 views

Route planning needs double click

I am new to Stack Exchange so i hope i can prepare my question in an adequate way. I try to make a small route planning application. A start address should be entered and the destinations are fixed. ...
1
vote
1answer
35 views

Keep direction information after intersect operation with fishnet

I will try my best to describe my question here: All the operations are done with ArcMap 10.1. I have a shapefile, which represent the stream segment network of a watershed produced from ArcHydro tool....
1
vote
1answer
276 views

Flip multiple vectors

I have thousands of vectors (out of several million) which I need to flip, for directionally purposes (Network Analyst). The vectors in question are annotated that their directionality has been ...
1
vote
1answer
481 views

Small Idea to get best path between two points

Guys I don't know if its a good place to post ideas or to ask general questions. Still as the question is related with maps service, I am posting it here. If it's not the right place, please move me ...
1
vote
2answers
3k views

google maps V3 : in javascript api, render route obtained with web api

I have to obtain route directions with the Google maps v3 WEB (http request) api (computations are made server-side, based on this data, without client interaction, so no JS available). Then, the ...
1
vote
0answers
30 views

Vector file with photo direction arrow

I need to make a shp file with photo points incuding link to each points photo and at the same time should each point have an arrow pointing in the direction the photo is taken. As the photo ...
1
vote
0answers
338 views

How to stop drawing the polyline in Google maps when path reaches in some defined area near the destination?

I am trying to draw the polyline between the 2 points and my requirement is, the polyline should stop drawing when it reaches the specified area surrounding the destination. I mean I don't want the ...
1
vote
0answers
73 views

Make a line from a set of GPS points close to a specific GPS point with PostGIS

I have to develop a map-matching algorithm. At the moment I only match GPS points with the closest road segment. I'm looking for a way to compare the directions between a GPS point and a road to ...