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11

Okay few things i would change and give another try: Make sure your featureNS value is in the "Edit Workspace Page under Namespace URI" in your GEOSERVER. Do not use something as generic as "http://postgis.org". Use something like "http://yourdomain/application/catalogLayer" or something unique like that. You can make this URI up, just make it unique. You ...


10

Direct tile access is not allowed by Google (and this is what ArcBruTile is doing). Usually this will get your IP address banned for awhile but they could also come after you for violating their TOS. fwiw, Arc2Earth will be adding support for this functionality in the next build. Instead of needing a Google Maps Premium license, you can purchase access at ...


10

Here is how I would do it in a Desktop. Get Quantum GIS Desktop, an Open Source and popular GIS Desktop. Install Openlayers Plugin(In Menu, Plugins -> Fetch Python Plugins would display the plugin) Set Project CRS to EPSG:3857 Add Bing/Google Satellite Layer( Plugins -> OpenLayers -> Add Bing/Google) Add PostGis Layer(Layer -> Add Postgis ...


9

Openlayers can't display rotated images as Layer.Image. If you want to display rotated images, you can use as workaround a vector layer with point feature and externalGraphic. Example of rotation: http://openlayers.org/dev/examples/rotate-features.html And example of rotation with graphic: http://openlayers.org/dev/examples/styles-rotation.html And ...


9

These are the basic steps you need to run through (is this what you have done? Apologies if this is too basic)... Make sure that your 1940 shapefile has an attribute containing county area (e.g. ‘Area1940’) use the Union tool (ArcToolbox > Analysis Tools > Overlay > Union) with your 1880 and 1940 shapefiles as inputs. Specify a new output shapefile. In the ...


7

That is how it is supposed to work. OpenLayers can't reproject WMS layers for you so you should let the WMS server take care of that for you. If your WMS can not support EPSG:32628 then you will need to look into setting up a cascading WMS that can reproject it for you (both MapServer and GeoServer 2.1+ can do this).


7

I think the problem is your time span. Its supposed to be in the format YYYY-MM-DDThh:mm:sszzzzzz (see KML Ref) "1944-06-06T06:2010-10-26T06:30:08 " is wrong in the "mm" part. Also, if you're trying to animate a set of time periods rather than points, you need timestamp rather than span. Time should be before and after according to the documentation ...


7

Given the sun's position, you can easily create a grid of the surface light intensity (ignoring atmospheric and topographic effects) in lat-lon coordinates. Reproject that grid as desired and overlay it on the map. The formulas are the standard ones for spherical coordinates: the unit vector corresponding to a spherical coordinate (lon, lat) is ...


6

Yes. ArcBruTile - Tile Services in ArcGIS Desktop ArcBruTile display tiles from OpenStreetMap, Bing, Google, SpatialCloud and TMS/WMS-C Services in ArcGIS Desktop. Update: looks like references to Google have been removed from the ArcBruTile site, likely because, as commenters point out, what they're doing violates the Google Maps ToS.


6

OpenLayers can transform vector layers (like WFS). If your vector layer is in EPSG:900913 or EPSG:4326 OpenLayers can handle the transformation itself, otherwise, it needs Proj4js included. There are examples of how to use OpenLayers with Proj4js. Raster Layers cannot be transformed by OpenLayers. If you need to include them in a different projection, you ...


6

It's not possible to mix geometry types in layers. You will need to add separate layers. Also, I'd recommend splitting the layers by topic, e.g. one layer with buildings, one with general zoning info. Don't just throw everything into one layer, otherwise you will have a mess to clean up later. Also styling is going to be easier with more layers. As @Willy ...


5

Just like set intersection, geometric intersection (which is essentially an intersection on two sets with spatially defined bounds) is both commutative and associative, e.g. (A ∩ B) ∩ C = A ∩ (B ∩ C) = (C ∩ B) ∩ A = C ∩ (B ∩ A). In practice, software often uses the order of inputs to determine how attributes are associated with the output; but the spatial ...


5

I am assuming you are using ArcGIS 10. Let me know if you are using a different version and I will change this for that version. First, make sure that your result shapefile from the intersection is in a projected coordinate system. It should be with the actions you have done already, but it is a good idea to check. Run Dissolve (Data Management > ...


5

What geographic/datum transformation did you use in ArcGIS? There aren't any for Bessel 1841 because that's an ellipsoid, rather than a geodetic datum. Is it really CH1903? Or CH1903+? The use of Bessel 1841 implies to me that the data originally came from a GRID or coverage. CH1903/CH1903+ wasn't supported in ArcInfo Workstation, so only the ellipsoid could ...


5

PBSMapping should fit your needs. There's a tutorial at NCEAS. The code below is adapted from that tutorial. I'm making assumptions about your data btw. Please edit as appropriate for your situation. library(PBSmapping) #prepare towns pts <- read.csv("towns.csv") towns <- points(towns$lon, towns$lat) # read in shapefiles rivers <- ...


5

As an alternative to the first answer, this approach uses flag fields on the parcel layer to indicate if the parcel contains upland forest or wetlands: On the parcel layer, add integer fields "has_forest" and "has_wetland" Select (by attribute) the "upland forest" landuse features Select (by location) parcel features that intersect the selected landuse ...


5

I would recommend clipping the raster to the shapefile, then in the resulting raster you can look at the number of cells present for each of your classes. The area can be calculated by multiplying the number of cells by the area covered each pixel (cell size squared). It's a different approach than the equally valid solution offered above but from a ...


4

From Graphserver you get a geoJson formatted file that you will be able to display with openlayers


4

Any good WMS should be able to do the reprojection for you. However I have no idea if ArcGIS Server is a good WMS. If it is unable to provide the layer in 900913 then consider using GeoServer or MapServer as a cascading WMS to handle the reprojection for you.


4

A couple geometry libraries I'm aware of include: Java Topology Suite, JTS Geometry Engine Open Source, GEOS OGR provides read/write access to many spatial formats and includes many, if not all, of the spatial operations provided by GEOS.


4

Your line ras_sub0<-rasterize(subarea0,raster_bath) is just taking the index number of the polygons and assigning that to the values of the raster. If you want just the intersection of your polygon and the raster: subarea0_bathy <- intersect(raster_bath, subarea0) Update: As @GodinA notes, looks like intersect() sometimes doesn't return a raster ...


4

v is a list. There is one list element for each polygon. Each list element can have many values (one for each raster cell that it covers). Therefore, you cannot simply combine the data to the SpatialPolygons (and you are not saying why you want to do that anyway). To get a single value for each polygon, you can use extract with a function (mean would be the ...


4

To continue webrian's suggestion: v.select ain=poly_a b_in=poly_b oper=within out=a_within_b Now the output vector "a_within_b" will contain those polygons from a that were totally within b. But be careful: when you import a shapefile into GRASS with overlapping polygons, the overlaps will be split up by the topology "clean" operation, so you'll have ...


4

Here is working code: options = { div: "map", zoom: 5, center: [-10796366.372312, 4426748.6429884], layers: [ new OpenLayers.Layer.OSM() ], projection: "EPSG:3857" }; map = new OpenLayers.Map(options); var noaaRdr = new OpenLayers.Layer.WMS( "Latest Radar", "http://nowcoast.noaa.gov/wms/com.esri.wms.Esrimap/obs?", ...


4

I recently performed a similar task, where I converted a series of 3D polygon shapefiles into KML files to view the data in Google Earth. I came across the Export to KML extension for ArcMap 9.3 or 10, which handles the export of shapefiles as KML, allowing labels, styles, temporal data and attributes to all be set and modified. I have found this extension ...


4

From the sp:over help: x = "SpatialPoints", y = "SpatialPolygons" returns a numeric vector of length equal to the number of points; the number is the index (number) of the polygon of ‘y’ in which a point falls; NA denotes the point does not fall in a polygon; if a point falls in multiple polygons, the last polygon is recorded. ...


4

You can't efficiently delete large numbers of features from a large table, period. You'd be much better off just marking them as deleted (available varchar(1), values 'Y' or 'N') and adding an attribute constraint to your selection logic (or using a view). Building a parallel table to house a foreign key and available field is an adequate solution, though ...


4

I think there is no better way than to handle zoomend event. To group markers by zoom levels, use L.LayerGroup: turning them on and off will be easier. Calling map.removeLayer() or map.addLayer() twice won't produce any errors or add a layer twice: there is an internal hash that prevents such things. So you can just have a bunch of if (zoom > 6 ...


3

The low-level spatial predicate operators are all binary—i.e., compare geometry A to geometry B. For example, see the DE-9IM topological model, which is the basis for Intersects, Contains, etc. When you have more than two, say geometry C, then you might need to compare the combinations of geometries: AB, AC, BC. But it all really depends on what you are ...


3

Hope this figure is explicit enough : From : http://www.gaia-gis.it/spatialite/spatialite-tutorial-2.3.1.html



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