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22

Vector data can have properties stored at two levels. File level or Layer level. For feature class (a type of vector data), file level information is stored in a geodatabase. This consists of properties like feature class geometry, attribute table, assigned subtypes and domains, a coordinate system, etc:. All these file level properties make up the actual ...


18

My thoughts are: Export your shapefile to a file geodatabase feature class - I think its drawing performance will be better but am not sure by how much If you are using ArcGIS Desktop 10.0 or later move it into a Basemap Layer - this will improve drawing performance dramatically If you like the sound of pyramids for vector data, be sure to vote for this ...


11

The MultiQML plugin lets you apply one QGIS layer style to multiple layers at once. I think that's as close to what you are looking for as currently possible.


9

which layer do you want, i dont understand? but getting all layer: map.layers getting all layer name: var mLayers = map.layers; for(var a = 0; a < mLayers.length; a++ ){ alert(mLayers[a].name) }; getting last added layer name: map.layers.getLast().name and beside this you can use all this method too: 1.map.getLayer() 2.map.getLayerIndex() ...


8

These terms specifically relate to the ESRI software and data schemas. A feature class is a set of common geographic features, for example roads, or parcels, or land use, as they are stored in a geodatabase or shapefile, or other storage format. Here is the help file on Feature Class Basics. A feature layer is the representation of a feature class after ...


8

There is no universal vector format in GIS. However, some formats are proprietary and other are openly specified (like the shapefile) so that they can be read and/or written by other softwares (if they decide to implement). For data sharing, the best solution to date is to use shapefile, which is now the most widespread format. Shapefile is however an old ...


7

Try... # substitute 'self' with 'qgis.utils.iface' when run from Python console # 'self.iface = iface' would usually precede this command in your class layers = self.iface.legendInterface().layers() for layer in layers: layerType = layer.type() if layerType == QgsMapLayer.VectorLayer: # do some stuff here Culled from consolidatethread.py ...


7

The easiest solution is to select the road segment(s) on the map or in attribute table and copy-paste (Ctrl-C - Ctrl-V) them into a text editor. You'll get the WKT string of the geometry with all its node coordinates. If you want to export the whole layer, an easy solution is to use "Save as ..." to CSV and specify OGR creation option "GEOMETRY=AS_XYZ" or ...


7

How about this: OpenLayers + any base map you want (or blank) & your data layers & GOOGLE MAPS layer with Custom Styles [search here on SE] as a data layer, not basemap => google maps custom styles created here: http://gmaps-samples-v3.googlecode.com/svn/trunk/styledmaps/wizard/index.html and here's one style that seems to work ok: Google ...


7

Yes, there is. Go to Options in the Settings menu and open the tab Map tools. Then you can set the Identify Mode. You probably want the Top down, stop at first.


7

You can do this by using Layer Groups. In the Admin interface, Under the 'Data' section on the left click on 'Layer Groups'. Then, in the usual GeoServer way, create a new layer group (by default you may already have a couple of examples) and then follow the intuitive interface to add layers to the group. Once you have your Layer Group created, go back ...


6

Perhaps the features were converted to graphics at some point. In that case, they might appear exactly the same as the original feature class but would not turn off with the feature class, since they are graphics. This is just a guess but worth a look.


6

"Layer" is an just an attribute of the feature. But you can use OGR SQL and attribute filters: import ogr driver = ogr.GetDriverByName('DXF') datasource = driver.Open('test1.dxf', 0) layers=datasource.ExecuteSQL( "SELECT DISTINCT Layer FROM entities" ) layer=datasource.GetLayerByIndex(0) for i in range(0, layers.GetFeatureCount()): layerName = ...


6

See my LIVE DEMO. Here is working code: <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Title</title> <script src="http://openlayers.org/dev/OpenLayers.js"></script> <script type="text/javascript"> function init(){ options = { div: "map", zoom: 2, center: [0, 0], ...


6

To georeference a vector layer, try the qgsAffine plugin. More info here: Where to find qgsaffine in the menu?


6

A SearchCursor in arcpy is the most direct route for accomplishing this: import arcpy fc = "c:/data/base.gdb/roads" field = "StreetName" cursor = arcpy.SearchCursor(fc) row = cursor.next() while row: print(row.getValue(field)) row = cursor.next() Note that you can use the where_clause property to perform your selection.


6

This is part of the raison d'ĂȘtre of the OGC. Regarding vector data you may wish to look into these standards: Geographic Markup Language (GML) - an XML grammar for the storage of geographical features. It serves as an open interchange format for the transaction of geo-spatial data between different software. Web Feature Service (WFS) - provides an ...


6

AndreJ and SS_Rebellious provide valid answers. However, there is another option which I find easier than creating the group and dragging layers in to it. You can select all the layers you want in your group (select multiple layers by holding down shift which selects everything between your first selected layer and the second one you click on, or hold ...


5

I am under the impression that the data source type matters more than the number of datasets: features stored in a file geodatabase will render quicker than shapefiles because of spatial indexing. EDIT: In a direct answer to your question I don't believe the number of layers matters as much in the desktop environment. I've seen articles about ArcGIS Server ...


5

what it means as conceptual, you can check out GIS Dictionary from ESRI, here. Feature Class In ArcGIS, a collection of geographic features with the same geometry type (such as point, line, or polygon), the same attributes, and the same spatial reference. Feature classes can be stored in geodatabases, shapefiles, coverages, or other data formats. ...


5

There are also two other ways: layers = self.iface.mapCanvas().layers() will give you a list of layers or layer = QgsMapLayerRegistry.instance().mapLayers() for name, layer in layers.iteritems(): print name, layer.type()


5

You can open layers contained in a project into the current QGIS session by using the Import Layers to Project plugin. This will let you choose which layers you would like to load into your current QGIS session. You could also take a look at the Embed Layers and Groups functionality. This allows you to open layers from a project. It stops you from ...


5

Woohoo! Figured it out. This thread had the solution to change the CSS rather than the JS. .olImageLoadError { /* when OL encounters a 404, don't display the pink image */ display: none !important; } This help article was helpful too, but I have not idea how to tell TileMill/MapBox to generate blank tiles rather than missing tiles. I'll get there ...


5

There are many tips for improving ArcMap performance which might help, but here's three suggestions I've used. I'd make sure the Data Frame coordinate system matches my shapefile's and any other layers I have on in the TOC; but the fewer layers to be displayed the better. I'd only use my symbology based on simple lines and fills without transparency or ...


5

You should be able to use the GetCapabilities method of the WMS server to list all the data and operations available to you. Something like the following (though I've not got access to test what this returns) should hopefully be what you're looking for: ...


5

When I load a bunch of layers into QGIS from PostGIS, they seem to load in reverse alphabetical order. This appears to be a bug (even in master branch) when using the add layer action Add PostGIS Layers... and should be reported on the QGIS bug tracker. However, if you use the new browser to load PostGIS layers, they will not be reversed. The new DB ...


5

The Openstreetmap plugin does what you want. Unfortunately, OSM hit a 64-bit-numbering limit, which forced all software using node numbers to be rewritten. The improved Openstreetmap plugin will be available with QGIS 2.0, which will be out within the next few months. Until then, you can look out for Geofabrik shapefile extracts. They include not all ...


5

Any file included in the Install\ directory of your add-in project will be carried along in the Python add-in when you run makeaddin.py. You can include layer files or anything else really. You'll find the absolute path to them on disk via path_to_layer = os.path.join(os.path.dirname(os.path.abspath(__file__)), 'mylayer.lyr') in your whatever_addin.py to ...


5

The styles are normally saved in public.layer_styles. Being in the public schema it should be accessible to every user. If not, make sure it becomes using: GRANT SELECT ON TABLE public.layer_styles TO users; -- "users" is a group with all your #normal users


5

Your downloaded shapefile already had a coordinate system defined in its *.prj file: ...



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