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6

I just checked my old National Atlas bookmark and was redirected not to the National Map Viewer, but to the National Map's Small Scale data page. There are 197 datasets available for download there, to my eyes it looks like it's the same data that was available at the old National Atlas page and they just moved it to the new URL. Are you not being forwarded ...


5

You're right Will, you have to save the features first before you can save it as a shapefile. When you toggle the editing icon to add your points, toggle it again. You should see a message come up: (Alternatively if you have the layer's attribute table loaded, you can save the features by clicking on the save icon). Now you should be able to load the ...


5

If you don't have an attribute, you should first find a polygon feature class with the boundaries of Greece (e.g. on gadm.org). Then you have two solutions : You want the roads to be cut at the boundaries of you area of interest : use some clip tools (in QGIS : Vector -> Geoprocessing -> Clip ) You want to keep the two sides of a road when it crosses a ...


5

Have you considered using a hosted solution? These days I only roll my own, when one of the cloud based services like ArcGIS Online or Mango don't have what I need out of the box. The spec you are describing is their bread and butter. Personally I find that Mango has the best mobile client. Their pricing is also sharper than ArcGIS Online for smaller ...


4

Reorganise your shapefile so that one shapefile contains one feature (A,B,C in your case) only Then use a loop like for i in A B C; do gdalwarp -cutline $i.shp ... $i.tif done to create each output raster. Example of script: #!/bin/sh # "shp" - folder for shapefiles # "outputraster" - folder for output rasters cd /home/user/cliprasters/ # ...


4

This is not an R solution, but Quantum GIS (QGIS) is a great way to achieve what you want. You can simply load the .osm file (Add Vector tool), right-click it in the Table of Contents and Save As ESRI Shapefile. QGIS may crash with such a large extract, so to avoid this you can uses OSM Tools like the OverPass API to download only what you need using ...


4

You can create a shapefile layer with your generic list of attribute fields and simply duplicate this layer within QGIS and Save as... another shapefile (or copy/paste the physical files such as .shp, .dbf etc). Then also save a generic style file and use these when dealing with clients. So basically, you have a shapefile "template" to work with.


4

You can take the layer you created for the first client, save it as a different-named shapefile, and then delete all the features in it.


3

Some issues in your code: you only use correctly one table as input whereas, you should use both input bufSHP and ctSHP you want to make an intersection between a list of shape and a filename with shapes.intersection(ctSHP) whereas you have to do an intersection between two shape elements See below a possibility, I choose to use Rtree to optimize, ...


3

While I'm a big user of both shapely and fiona, I wouldn't go this approach. This is a task of writing an effective SQL statement. Using ogr2ogr with an SQLITE dialect, you can process this from a command line. Change directory to one before the shapefiles, so that all of the shapefiles are in one directory called data. OGR treats directories of shapefiles ...


3

You can do it with ogr2ogr at the command line too by using the -where flag. ogr2ogr -f "ESRI Shapefile" -where "FID < 0" output_template.shp input.shp What this does is execute a SQL where query and selects those features with a FID less than 0. None should exist because FID's usually don't have a negative or below zero value, so no new features are ...


3

May I suggest the Census Bureau as one of the options? You can access ftp sites of the available shapefiles in any of three ftp sites: ftp://ftp.census.gov/geo/ http://www2.census.gov/geo/ ftp://ftp2.census.gov/geo/


3

Two other US government sites I use that provide similar (and in some cases duplicate I believe) datasets as those found on the National Atlas are: USGS Earth Explorer: http://earthexplorer.usgs.gov/ USDA Geospatial Data Gateway: http://datagateway.nrcs.usda.gov/


2

when you are at the step of exporting, look at the bottom of the dialogue box and make sure the type is set to shapefile, sometimes it defaults to dbf. Hope that helps.


2

If the Excel sheet contains point coordinates and you want to make a shp, you first need to create an event layer. File, Add Data, Add XY data. Then you can go to Data, Export Data to create your shp.


2

The above code looks more like you just clone shp into shputm and then assign the output of crs(shp) to shputm without performing an actual reprojection. Anyway, if you import both the shapefile and the NDVI raster, and then reproject shp using spTransform, subsequent data extraction should work out fine. Also, the output of extent(shp_utm) roughly agrees ...


2

If I understand your question correctly, it sounds like want to have three points created for each row in your table (one for each of the three fields). When ArcMap imports a table like this, it will only create one point feature for each row in your table. So if you want it to create three points per row (one for each of your fields given for each ...


2

Try editing your table so the field names don't contain spaces, special characters etc. That's what causes the error on export to shape, and may be the root of some of the other issues you have as well...


2

DIVA GIS will give you roads and municipalities (and I think departments). OSM will give you roads, municipalities and some POIs (and I think departments). Natural Earth will give you municipalities and roads (and I think departments). GeoCommunity will give you roads, municipalities and places (and I think departments). GeoNames will give you places.


2

You can also use a polygon to select the roads you want (in the top menu bar, the icon with the white arrow and the dotted lines). Then click on the layer containing the roads >> save as shapefile. If you make sure the box 'only save selected feautures' is thicked, you're new shapefile should only contain the selected roads.


2

Here is the source to the underlying Java library, prj2epsg, used behind the scenes on the webpage you list. Basically, it uses a Lucene index to get the best match between the WKT in your prj file and an underlying EPSG. As AndreJ has already said, this may not be 100% perfect, but Lucene excels at partial/fuzzy matching. gdalsrsinfo might be easier to get ...


2

There is no such tool working 100% perfectly, because there are many EPSG codes that share the same projection parameters. You can run gdalsrsinfo on any Geotiff or shapefile .prj file to get the proj string out of the definition. For some intelligent ways of guessing, follow the answers given here: Identifying Coordinate System of Shapefile when Unknown? ...


2

Figured this out! (also asked here) A record in a spatial table (Shapefile, PostGIS, Spatialite) that has no geometry can have geometry added by adding a 'part' to the feature using the advanced digitizing toolbar. Here's the workflow: Bring table containing the geometry-missing feature into QGIS Select the layer from the layers panel and start an edit ...


2

@jazzurro, you perfectly can do this with R, just look up osmar package! Read the osmar documentation (osmar.r-forge.r-project.org/RJpreprint.pdf). At pages 11 pp. you can find a detailed example for extracting roads/highways by the according tags for munich.osm! After pulling and extracting the data from a planet file for Australia you can convert to any ...


2

With your example, polygon is a standard Python dict object that represents a GeoJSON geometry, which only uses standard data types, with no fancy geospatial properties. But you can convert polygon into a shapely geometry, as you have done with shape polygon = shapefile_record['geometry'] shape = shapely.geometry.asShape(polygon) print(shape.bounds)


2

You might see both datasets aligned because On-the-fly-reprojection is enabled. This works when both datasets have different CRS. Other software does not offer this tool, so you have to reproject one of your datasets to the CRS of the other to make them align in every software. BTW this applies also to some tools integrated in QGIS, like intersection or ...


2

I find openWind normally works very well so, without any further information, I suspect you are spot on about mismatched CRS. According to the documentation: openWind is fundamentally based on a meter grid so the projection only comes into play when converting to and from geographic coordinates. openWind does not carry out on-the-fly projection so ...


1

File from the Website is in KMZ format 204.12.153.232/GEarth/World/PNAV13.kmz Loaded into QGIS and saved as a shapefile. Labels are in the Name Field which is then labelled.


1

"Add feature" came back! A green X on endpoint of a line on a different layer than I wanted to use and that was left over from a previous session (and that I could not turn off, even after restarts and reboots) became a start point once things suddenly began to work. Still a mystery.


1

Canada Post keeps a tight reign on its claimed copyright of Canadian postal codes. The site 'geocoder.ca' referred to in the update is one of several sites that Canada Post has dragged into the Canadian court system. Basically, Canada Post makes money selling the information. Canada Post has gone so far and trade mark the spelling 'Postal code' (note the 'c' ...



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