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4

File Geodatabase in QGIS 2.4 Note: Use Directory rather than File Once the file geodatbase is loaded save the shapefile


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Convert from shape to gmt use this example code : ogr2ogr -f "GMT" Hudson_bounds.gmt Hudson_bounds.shp


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I see that you were able to use a plugin to get the values you wanted, but here's why the values were changing in the first place. This isn't specific to QGIS or any other software, it's an issue with how the data is being stored. Floating point values are stored with a specific precision (number of digits). Some software will automatically round the stored ...


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This set of extracts from OSM data may be what you're looking for. In particular, this shapefile of the coastline around Helsinki.


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The type of relationship between your two levels of polygons is not perfectly clear, but I think that you could do this in a few automated step in any cases. Case 1 : Many to one relationship. In other word, the smallest polygons are never overlapped by more than one type of the larger polygons. In this case, you can use "intersect" or "spatial join" that ...


2

The ogr2ogr clip operation creates polygons but for some reason also linestrings to to South and East edges of the area. Pink lines below show those 100 linestings (one is selected). Because of mixed geometrytypes the result cannot be saved into shapefile and therefore the error. I am not sure if this is an intended behaviour of ogr2ogr clipping or a bug. ...


2

Hi The column time 4th is like "2014-05-30T16:32:39+0000" and I´d like to format it as '30 / 16:32 UTC' to show this in the label. For that you can use Regular expressions: you want to extract '30T16:32' from the string (This isn't geospatial but ...) The pattern (regular expression to be matched) is [0-9]+T[0-9]+:[0-9]+or \d+T\d+:\d+(search for the ...


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Many of these (3 of the 4) can be found in open street map. Here is some good information on obtaining the data http://wiki.openstreetmap.org/wiki/Downloading_data and here is some info on converting it to shapefile. http://wiki.openstreetmap.org/wiki/Shapefiles


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If you use geoserver's Shapefile Output on the WFS service, it doesn't matter what the source of the data was. It doesn't matter whether the data is coming from Shapefiles or PostGIS or something else. Let me try to provide answers to all your sub-questions. It doesn't matter about how big the table was, or how many features it contained, Geoserver can ...


2

You should really be doing this in edit mode using the editor toolbar. Rather than creating graphics or converting graphics to shapes, create the shapes directly in the file. See the help topics and its subtopics


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The controls on the map appear to be OpenLayers. Here's how you can find out yourself what kind of data it's using in the client in Chrome or Firefox: In Chrome, go to Menu > Tools > Developer Tools and switch to the Network tab. In Firefox, go to Menu > Developer > Network Refresh the page, pan around the map a few times, see what resources load.


2

You should be able to export the shape file as a GeoJSON file from QGIS. With the shapefile added to your map, right click on it in the legend/TOC and click on 'Save As...' in the pop-up menu. Select GeoJSON as the output format Keep in mind that while it is valid JSON, the GeoJSON output this way may not be in the exact format you are expecting. OGR ...


2

As you can see from the comment thread above, layer files and relative paths are a bit complicated. The problem is that a layer file (*.lyr) can either hold absolute paths or relative paths, but there doesn't seem to be any (easy) way to ascertain which it uses, after the layer file has been created. To create a layer file with relative paths, there are ...


2

Open a new dataframe, don't add a basemap, just the shapefile, move your mouse around on the screen and look at the coordinates towards the middle are they small numbers that look like latitude and longitude? Open windows explorer and navigate to your shapefile... look for a *.prj file, if you don't have one, then you are working with data that no ...


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Once you get the shapefile/projection problem solved: Kriging is a method of interpolating points to create a continuous surface. I think that you actually want to use graduated colors to modify the symbology of the points, manually setting classification breaks at the values you need.


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For geoprocessing, I suggest to turn on-the-fly-reprojection in QGIS OFF to see whether your shapes align or not. In many cases, geoprocessing does nor work when the shapes are in different CRS. So save your polygon layer as WGS84 EPSG:4326 (do NOT use Set CRS for Layer for that!), to match with the points layer coordinates. For the NaturalEarth dataset, it ...


2

The point feature is a bit more straight forward once you have your table in excel (with your X and Y columns), save it out as a .csv and you may use the Make XY Event Layer tool to convert to event layer and then use Feature Class to Feature Class tool to convert to shapefile. The polyline and polygon are not as straight forward, you will have to build a ...


2

JJD yes there is. I haven't used it myself. You use the -m option and pass a mapping file that has the old column name and new column name on each line. As Ryan alluded to here: http://www.bostongis.com/pgsql2shp_shp2pgsql_quickguide.bqg I suspect he was thinking of -m and mistyped -f. Hope that helps, Regina


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If you are willing to program python: arcpy has the "fromWKT" function, which can read a WKT string and return a geometry object. See http://resources.arcgis.com/en/help/main/10.1/index.html#//018v0000008s000000 . FME has a WKT reader also: http://docs.safe.com/fme/html/FME_ReadersWriters/Default.htm#wkt/wkt.htm


1

Yes, the extent isn't accurate. If you have spatial analyst extension then use IsNull to create a binary raster, raster to polygon (no simplify) and then dissolve with no fields to create a clipping polygon. Once you've got that then just clip as normal. If you haven't got Spatial Analyst then it's a bit more tricky.


1

I'm guessing based on your final image that while the green does provide 100% coverage, it is broken up into separate polygons - otherwise (if it were a single giant polygon) you'd be getting nothing selected. The problem is your Relationship choice. Within means that only whole polygons (not areas or parts of polygons) from layer A that lie within a ...


1

The WLmap2_polyline data is using WGS 1984 UTM zone 24N, but the data is actually in zone 20N. Denmark uses a wide-area implementation of transverse Mercator for Greenland. I checked against ArcGIS and our "complex math" version of TM doesn't improve the offset. Or the data was projected into UTM 24N using the a more standard UTM implementation and that's ...


1

There are a number of ways you can accomplish that. You can use ogr2ogr clipsrc if you have your ellipse as a shapefile: ogr2ogr -clipsrc ellipse.shp output.shp input.shp And since you tagged this question with pyshp, you can also use that. The code below demonstrates the concept you mentioned using an ellipse and randomly-generated points. If you are ...


1

Firstly, you should do Feature To Point in order to create your centroids. Then, you obviously need to create your buffer. For the third step is to use Tabulate Intersection to know how much of each polygon is under your buffer. Finally, you summarize your table to get your synthetic value and you join the resulting table to your original polygons (or to ...


1

For the HEIGHT it would be with respect to ground. For the ELEVATION, most countries have a national geodetic survey that should be used as a reference. Those NGS are usually defining their own MSL. What you usually extract from an existing dataset is the elevation. The height can then be computed as the difference between elevation at the top and the ...


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Normal convention in my locale is with respect to ground since elevation above MSL would be meaningless to the average user.


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You seem to be using a dynamic workspace, which I don't think is right here. Assuming you want FME to create the new table, the following steps should be what you need to do: 1) Open the Generate Workspace dialog (Ctrl+G) 2) Enter Shape as the source format 3) Use the browse button and select ALL of the shape files to be converted 4) Set the output ...


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One way of approaching this is with the following technologies: Server with PostGres/PostGis, GeoSever and a Web Server installed. (Could be a windows desktop machine using IIS) This will allow you to import the shape files and KML files into a database with geometries and create layers to present to the end user You will need to build tables of vehicles ...


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You do not need to recreate the datastore every time. It is just a pointer to a location on your disk. In the case of shapefiles, you can simply copy the new ones into the relevant folder and (assuming the files have the same names and are already referenced as layers in Geoserver), the update is done (without touching Geoserver). Given the number of ...


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Technically yes, it is possible. However there are no packaged tools with SpatialNET to do so, so if you were to do it (which I would advise against in the strongest terms) the method would be to build the data in ArcGIS and then bulk-load it to the Oracle Spatial back-end of the SpatialNET instance. (There is also a Python API that you could use to build a ...



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