A coordinate-based data model that represents geographic features as points, lines, and polygons.

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4
votes
1answer
371 views

How to know contents of column names in GRASS?

I am using GRASS to extract a specific area from a vector map. Here is the script that I am running: v.extract PHL_map out=makati where="AREA_NAME = 'Makati" The problem is, I don't know what are ...
4
votes
2answers
891 views

Calculate spacing of polylines along transects in ArcGIS

I have a shapefile with a number of roughly parallel lines in it, and I want to calculate the spacing between these lines using a number of transects across the map. How should I go about this? I ...
2
votes
2answers
568 views

How to query data from a vector map (shapefile)?

We want to obtain the specific place of the boundaries of a shapefile. We want to be able to get the points of each polygon corresponding to a specific place in order to use these data in an ...
3
votes
2answers
1k views

Working With Vector Product Format (VPF) - APIs, etc

I've been looking around the Internet for information about Vector Product Format. I want to put together a project that can read Digital Nautical Chart (http://msi.nga.mil/NGAPortal/DNC.portal), ...
4
votes
4answers
6k views

Merge overlapping lines in ArcGIS

I have a polyline shapefile containing a number of lines, some of which overlap. By overlap, I mean that they follow exactly the same path for some of their route, but also have bits that are not ...
3
votes
1answer
492 views

How to sensibly digitise this raster, scriptably, in ArcGIS

I have the raster below which I want to convert to a set of vector lines: As you can see, there are small breaks in the lines and some bits are double-width. I want to be able to reliably import ...
3
votes
4answers
3k views

Scriptable way to merge polylines that join in ArcGIS

I have a number of polylines (around 9000), a number of which have one or both ends touching another polyline. I would like to merge these ones together into one polyline - thus reducing the number of ...
4
votes
4answers
2k views

Openlayers WFS Vector Layer Rules dont get applied

i have a script which applies rules to wfs.vectors. the script works fine in firefox and all the rules get applied, but somehow when i open the same file with the internet explorer 7 / 8 , only the ...
5
votes
3answers
7k views

Free Mercator, Vector Maps

Are there any free, vector, mercator projection maps available online? I'm not wanting satellite imagery, but more a stylized map along the lines of this: However, I need it to be vector-based such ...
7
votes
4answers
578 views

Comparing 2 vector files

I'm looking for a tool which compares two vector files (eg shapefiles). Eg 2 versions of a river network. Quite a lot of the records are equal, but some are different. A possible output would be eg a ...
4
votes
8answers
1k views

Any Good Map Rendering Engines for SqlGeometry/SqlGeography

Can anyone suggest good map rendering engines for MS SQL Server Spatial types (SqlGeometry/SqlGeography)? By rendering, I mean plot the geometries to a common image format such as png or jpeg with ...
15
votes
3answers
1k views

What is the wire format for Google's new vector map tiles?

Google recently released new vector cartography for their mobile maps. I'm curious if anyone here has any insight into the wire format they use for transmission? I've experimented with a few formats ...
6
votes
1answer
426 views

How to use simplify()

i have my Vector Data saved in a PostgreSQL PostGIS enabled Database. The Data im displaying is very detailed, i want to simplify it through the simplify() method of Postgis. I duplicated one of my ...
14
votes
3answers
2k views

Rubber sheeting in GRASS or QGIS

We are in the process of getting our property boundaries corrected and a side effect of this is that we need to move any assets that have been drawn relative to the property boundaries, so they are ...
4
votes
4answers
308 views

Enlarge/roughen the Vector Size of Tiles

Im currently running a GeoServer and my task is to make the vectors rougher thant they are right now. I really dont know where and how the Geoserver processes the data from the DB and how it will be ...
-8
votes
3answers
1k views

Delivering map tiles in real-time without caching? [closed]

I am wondering how useful would you find to have a way to deliver map tiles quickly over the web without worrying about caching or seeding them? With raster map engines we know that this is a ...
5
votes
1answer
940 views

Programmable buffers using GDAL and python

Is there a way to programmatically generate buffer layers for vector layers using GDAL and python?
4
votes
3answers
2k views

How to calculate orientation of line segments using open source GIS?

I'd like to calculate the orientation of line segments relative to north direction using open source tools. Which tools or functions would you recommend?
7
votes
4answers
3k views

How to calculate polygon length and width using open source GIS?

How can I calculate the length and with of polygons using open source tools? By "polygon length" I mean the length of the longest line within the polygon (update: to be correct, I just need the ...
7
votes
3answers
629 views

How to get a list of adjacent lots to a road in ArcMAP and PostGIS/QGIS?

In the following map, I have: A line / road layer A parcel / lot layer The Task: Find and count the list of lots adjacent to the road with their types (parcel_type is a field in the parcel ...
4
votes
5answers
3k views

Problems merging DEMs or other raster datasets? Clipping Raster dataset to vector line?

I have two DEMs that I am going create a hillshade from, and ultimately want one hillshade clipped to a county boundary. I am running into a couple problems, though. When I try to merge the two ...
1
vote
1answer
102 views

How to reference vector based data to raster data that already has spatial reference in MAPublisher?

I have been able to load in raster data into MAPublisher and properly registered it, however I have been having trouble with a further step. I am trying to reference vector data that has no GCS or ...
20
votes
7answers
7k views

Nearest neighbor between a point layer and a line layer

I've asked this question several times on stackoverflow and irc between #qgis and #postgis and I also tried to code it or implement it my self in postgis with no real answer. Using programming (most ...