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8

Those leading figures you ask about are the Eastings and Northings of the SW corner of the "medium" square "U" which is inside its parent large square "S". Each large square is 500km wide, as you state. Each large square is further subdivided into 25 "medium" squares, 100km wide. I call them medium squares because they too, as you know, are subdivided ...


7

There's the Ordnance Survey OpenData now. You could try the Strategi product. This has urban_region polygons, but they don't have names since they are often several towns now in a conurbation. Combining with the settlmnt_point layer you could use that to get the names. Here's the polys and points on top of a google maps layer (done using QGIS) As you can ...


7

If you simply want to dissolve the edges and are happy with having one large multipolygon feature of all buildings, you can simply use the fTools "Dissolve" tool ("Vector/Geoprocessing/Dissolve"). If you want to keep the attributes (in the case of OS Vector that would only be the ID, which seems to be rather arbitrary), you can split the dissolved vector ...


6

It depends how you define cities. The strategi dataset contains a cities layer. If you wish to have more detail, and include large towns the Meridian 2 dataset contains an urban area layer that would be a good starting point. You could also use the Boundary Line Data from the same source that would give you the administrative Boundary associated with ...


6

Are the TIFs tiled? The OS Vector District raster images I have aren't. To find out using QGIS, load one of the rasters and select Information in the Raster menu. Click OK, and somewhere after the projection and metadata you should see a line something like: Band 1 Block=4000x65 Type=Byte, ColorInterp=Palette If, as in this case the block size is the width ...


6

KML files are always WGS84/lat lon (EPSG:4326). Save the KML file as an EPSG:27700 shapefile instead. Alternatively, you could download the Ordnance Survey OpenData Boundary-Line dataset, which is already in EPSG:27700. See: https://www.ordnancesurvey.co.uk/opendatadownload/products.html N.


5

As suggested by other answers, the problem is related with the POINT and MULTIPOINT types. shp2pgsql (and ogrinfo) detects the geometry type as MULTIPOINT, but then, when creating the EWKB representation of the geometry (the value to insert in the_geom column), it seems to be generating a POINT geometry: select ...


5

The 'National Grid Shape file' can be downloaded at: https://github.com/charlesroper/OSGB_Grids Using this for a OS grid at a specific resolution would take some aggregation based on the TILE field, or by using the SCALE field.


5

Here, the XSL file is a style sheet language file (XSLT, or eXtensible Stylesheet Language Transformations) for transforming the XML file into other XML documents or other objects such as HTML, plain text, pdf, etc. A priori nothing to do with QGIS, especially if one looks OS MasterMap® style guidance Transforming GML using XSLT These styles are ...


5

I'm assuming that you are using the Meridian 2 data from the Ordnance Survey and have used that and your data to create the chart below. I have stripped away the parts of your code that seemed to me to be redundant. Basically as far as I can see you want to automatically remove points that do not fall within the area in question, in this case the county of ...


5

The SLDs were originally created for our own use in GeoServer which supports several vendor specific options that we use for our OS OnDemand Web Services, so there are some edits that you need to manually make to the SLDs for them to work in QGIS. The first is that in the SLDs we top and tail each rule with the <FeatureTypeStyle> ...


4

Not me but Adrian Walker has 'Using Ordnance Survey OpenData Street View Rasters With GeoServer' http://www.adrianwalker.org/2010/08/using-ordnance-survey-open-data-street.html Some good tips there (especially if on linux platform) Some python code is available at the bottom. Or are you looking for Vector examples? ...


4

The full license text is available at the OS website. Looks relatively simple - you can use it commercially if you want, but you must attribute them.


4

Your example grid reference only has 4 digits and thus specifies a location which is 1km square, so plenty of room for a 500m error there. See Ordnance Survey grid digits for examples of numerical resolution. More digits will give you more accuracy.


4

I think you'll need to georeference the base image and then capture your vector layers manually drawing over it. This seems like a similar proccess: http://geo.nls.uk/urbhist/guides_vectorlayerqgis.html but not exactly what you are looking for. If you're unfamiliar with georeferencing this looks like a good guide as well: ...


4

For administrative boundaries, GADM is always the best free source: http://www.gadm.org/download adm_2 includes the counties and larger town boundaries. If you need more, have a look at what Ordnance Survey offers as OpenData: http://www.ordnancesurvey.co.uk/business-and-government/products/boundary-line.html For the post code data (which is not ...


3

I don't know why you are getting that error, but I just tried to load your zipped shapefile using the SPIT plugin in QGIS, and it imported just fine. This surprised me as I assumed SPIT was just a gui for shp2pgsql! I am using QGIS 1.6 on windows but it should work just as well on fedora. Hope this helps Jo


3

I found this on the Ordnance Survey Blog Map data video from 2004 to 2011. http://www.youtube.com/watch?feature=player_embedded&v=lvmcYvcJY2I source: http://blog.ordnancesurvey.co.uk/2011/04/3974/ (try contacting the author of the blog.)


3

You don't mention the time period you are interested in but if it is long term then you might find the resources at http://visionofbritain.org.uk useful. They have raster scans of OS 1st and New Popular series maps.


3

Regarding execution times: Lanczos is extremely slow, but other resampling algorithms produce similar (perhaps even better) results: near (11s) bilinear (17s) average (27s, a bit soft) bicubic (30s, called cubic in GDAL, text thickness sometimes odd) antialias (45s, requires pil and numpy) cubicspline (1m53s, way too soft) lanczos (11m8s, extremely ...


3

You can add this projection to the projection table postgis uses and then refer to it with the new name (97460 or SR-ORG:7460 in this case): INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 97460, 'sr-org', 7460, '+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +datum=OSGB36 +units=m ...


3

Ah, I've done some of this. Probably the best way of georeferencing old Ordnance Survey 6" maps is to use OS Grid coordinates (not grid references and definitely not lat/lon). If your map images are true, undistorted scans you might, with luck, be able to do this using just two points. What I normally do is find two features on the map that still exist ...


3

GIS file formats contain georeferencing information. This ties image pixel coordinates to grid references in a projection system, in this case British National Grid. There are lots of ways this information can be stored depending on image format. A basic tool to get you started is gdalinfo which will query the extents of the image in British National ...


3

The way I see it you have two main options. 1) Sign up for OS OnDemand - OS OnDemand is Ordnance Surveys WMS service. once you have access you can call it via a standard OpenLayers WMS call. This is not a free service. The licence for an external facing application is £20,000 a year. They do provide a free trial though. 2) Set up your own WMS loaded with ...


3

These can be found here. These were found via the wonderful ShareGeo website: http://edina.ac.uk/projects/sharegeo/content.html Edit - they can be quite slow to load - but do cover the entirety of Great Britain. No coverage for Northern Ireland unfortunately:


3

You can find the geo referencing files on our website for each of the raster products Download TFW Here Download the correct zip file and unzip it into the same directory of your .tif files Any GIS will then work with the raster files


3

IGN France has a good equivalent the Ordnance Survey MasterMap formally AddressPoint now Address Layer 2 database. http://www.ordnancesurvey.co.uk/business-and-government/products/address-layer-2.html based from many years of working very closely with OS addressing, it is in conjunction with Royal Mail (privatised in October 2013). Accuracy, it is ...


3

You can find the OS Grids here https://github.com/charlesroper/OSGB_Grids Download the shapefiles and then load them in You will probably need to adjust the styling and turn on labelling using the tile name as a text label


3

After calculating areas of the 1km grid shapefile rectangles, I can confirm that the single cells are not precisely 1km². The error is small, though. If your errors are larger, it is possible that your problem is related to a different issue (possible reprojection errors). Small errors in the source dataset Most of the calculated areas are less than 10m² ...


2

OS has started an open source effort called OS OpenData which provides a number of 'open' datasets. The lack of publicly available UK data was part of the impetus for OpenStreetMap (OSM). Cloudmade has some easy-to-use extracted data, and other download options via Planet.osm.



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