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5

The answer to this kind of issue should be to rasterize the information on to tiles on the server and simply serve the user tiles of the routes that they want to see. There are a plethora of options for doing this, but I think this train of thought is the best solution. Render the desired view on the server and only pass the tiles to the user, wash and ...


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 ...


2

Here's one way, using Numpy and GDAL. Read your 125m resolution raster into an array that is 25x larger in each dimension. GDAL's I/O function decimates for you and this feature is available in Rasterio (https://github.com/mapbox/rasterio/blob/master/docs/windowed-rw.rst#decimation) and I assume also in osgeo.gdal. Ask the methods to write into an array ...


2

Even if you find historical maps that use a cylindrical projection, or even Mercator projection, they're not going to overlay without further work. Even in the Mercator case, the datums or projection parameters will be different. You can try to georeference the historical map to reference data that's in a coordinate system as close as possible to the one ...


2

This might be a way. I use this World map shapefile # Read in new shapefile world <- readOGR("~/test", layer="TM_WORLD_BORDERS-0.3") # Order after $REGION in the 8th column world_attri <- world@data[ order(-world@data[,8], world@data[,1]), ] # Extract first line of each unique $REGION world_attri <- world_attri[!duplicated(world_attri$REGION),] # ...


2

What you're trying to do is known as apportionment. This takes a numerical attribute value of a feature and divides it in some way between pieces that feature is split into. There are a number of different solutions. In fact, there's a specific tool for it in the Business Analyst extension, but you probably don't have that. Esri has also published a ...


2

The simplest solution is probably to create a topology with the Must Not Overlap rule, select all errors in the Error Inspector window, right-click and choose Substract: You can find out how to create a topology here if necessary. You can create the topology, add feature classes and rules with ModelBuilder with the tools from the Topology toolset, but you ...


2

This is an example of what you can do with rasterVis and sp packages. You will have to adapt to your own use. library(rasterVis) library(sp) # Download States boundaries (might take time) out <- getData('GADM', country='United States', level=1) # Extract California state California <- out[out$NAME_1 %in% 'California',] # Plot raster and California: ...


1

Because of the way the BoM appears to produce those images, the "content" will always be in the same locations in geographic space, and in the same location in pixel space. So you should be able to use a Leaflet JS image overlay, specifying whatever turns out to be the equivalent of the outer bounds of the source PNG for the imageBounds argument. An ...


1

You can open Esri file geodatabase in QGIS. I am not real familiar with how to run the analysis in QGIS, but I am pretty sure it can be done.


1

My quick testing, using ArcGIS 10.2.2 for Desktop on Windows 7 SP1, indicates that Intersect is faster than Spatial Join. This test, run from IDLE: import arcpy,time if not arcpy.Exists(r"C:\temp\test.gdb"): arcpy.CreateFileGDB_management(r"C:\temp","test.gdb") if arcpy.Exists(r"C:\temp\test.gdb\fnPoly100"): ...


1

Intersect, or Union as Aaron mentions, are Overlay tools that should get you a set of polygons that have attributes of both. Identity is also an option if you have an Advanced license, and is probably the most suitable for your end goal. Basically you want to cut up land use polygons if they cross a catchment boundary and then assign the catchment id to the ...


1

Just to be clear, the 'old' raster(s) is/are NOT in a Mosaic dataset currently, and the old raster is in one large (seamless) raster. The 'new' rasters are tile-based and have already been loaded into a Mosaic dataset. Here is my recommended solution: Create an 'old' Mosaic dataset from the 'old' seamless raster using the tile boundaries from the new ...


1

I would look into Synchronizing Mosaic Datasets, this should add the newer imagery on top of the older imagery. You can then change the mosaic method you use, to sort by a date field when the image was captured.


1

No, you cannot do that or those sort of tasks in Google Earth. Your best investment would be QGIS. Use the OSGEO Network Installer if you can. The process you will use depends on the format of the map that you propose to overlay. Is it another vector layer? If so, is it a complete polygon or just a line which encloses the area of interest. For a one off ...


1

Your problem is that WFS 1.0.0 does not support reprojection of the coordinates. If you switch your request version to 1.1.0 then GeoServer will take your srs into account.


1

I would use the georeferencer to get the jpeg in the correct position and then digitise the lines/boundaries so that you dont have to have the jpeg in the model anymore


1

Frequency and summary statistics were definitely present in version 9.2, frequency has been around since I've been using ESRI products (early 1990's). Summary Statistics offers more powerful statistic types over frequency, and can work with a basic license (ArcView) where frequency needs advanced (INFO) license. Same with Intersect, Identity and Union, ...


1

If you do not need the bathymetry, then don't combine the sea raster with the land elevation raster. Instead use it as a mask as follows: Make your sea polygon into a raster: v.to.rast sea output=sea use=value val=1 Then make a land area raster ("inverse" of the sea): r.mapcalc "land_area = if(sea==1, null(), 1)" Now set the land_area as a mask, and ...


1

you seem to have just two cases, so a conditional statment (using map algebra or raster calculator) could help Con( IsNull(C4), float(C1 + C2 + C3)/3 , float(C1 + C2 + C3 + C4)/4) In this case you apply a weighted overlay (with the same weight) that is different with or without NoData in C4. Note that you can change the weights if you want (see below): ...


1

I don't think this is the cause of your problem, but you are misspelling maxResolution in your code. It might help you to use a tool like Fiddler or FireBug to look at the request urls of the WMS layer. For a start, check that the coordinates getting passed are in the correct projection.


1

there are two main logical operators : the AND and the OR. In fuzzy logic, you can use: "fuzzy AND" as an equivalent of the minimum of the different membership values "fuzzy OR" as an equivalent of the maximum of the different membership values if you want to combine this with your crisp decision, you can convert "yes" to 1 and "no" to 0. Then you can ...


1

What I want to know is the number of the red dots that are present in just one area defined by the black line. Vector | Analysis Tools | Points in Polygon will count the number of points for each polygon. Update: Since your "dots" are indeed lines - as the icon in the layer list indicates - try using Vector | Analysis Tools | Sum Line Lenght. It adds ...


1

You can find a lot of historic maps online digitized by American Libraries. A few examples: http://www.lib.utexas.edu/maps/ http://lib.byu.edu/digital/germanmaps/ http://www.wildernis.eu/chart-room/ Unfortunately, Only few write the used projection onto the map. Cylindrical Projections are common for Northern America. In Europe, Mercator and Transverse ...



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