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0

I believe your expression should be: left( "SITE_ADDR", strpos( "SITE_ADDR", ' ' )) Note single quotes around string, do not need to minus 1.


4

You don't need a plugin, just use the toolbox: (QGIS) Geoalgorithms > Vector creation tools > Create Grid


4

Look at the Processing Toolbox and you may choose many algorithms without the need of a plugin


3

"QuickWKT" by Alessandro Pasotti is the simplest way to create a point layer knowing it's coordinates "New Memory Layer" plugin by Boris Jurgiel allow you to create a memory layer that you can edit adding point features probably there are others that I don't know ;) regards


2

You need to create a spatial join. The MMQGIS plugin does this quite easily - MMQGIS -> Combine -> Spatial Join. A tutorial is available here.


0

In newer QGIS versions (I tested it only in QGIS 2.6) you can set the resolution when you save a raster via "save as" (quite similiar with ArcMap)


0

A clip operation should be cutting the features that cross the clip layer at the boundary - that's what clip means. Based on a tutorial in the documentation (section 9.4.20), QGIS does support selected feature input to geoprocessing, at least in this case. Make sure your districts are on top in layer order and select the target district. Then run Vector > ...


2

Use the substr function under String list for example: substr( 'L3NAM1988K', 6, 4 )


0

I found it! Editting the model in the "Processing modelelr" window so the minimum contour value will include negative values (by default, the minimum level is st to 0). I still don't know what caused the error message I posted above, but it might just be a problem with the data set, cause the model works fine on other data sets.


2

You can use the Freehand editing plugin (not to be confused with the trace edit tool). Get this by installing it through the plugins menu option. Another option would be to use edge detection in the Processing toolbox (Have a look at tools in GRASS and Orfeo. SAGA maybe has one too I forget). The downside of this is that it will detect all edges. What I ...


0

Thanks for the idea, I tried it, but with limited speed up. Isn't there a way for a direct memory access? I load the same data with python in Paraview which takes 10sec for 600 000 triangles. QGIS takes >1h ... And, not only changing attributes, but also shift painting triangles or shifting geometry.


2

Remove the outline of the feature style in Layer Properties | Style or turn it white - depending on which effect you prefer.


4

if you use the Kyng Chaos version: 1) First solution with the PYTHONPATH variable: Add qgis to the PYTHONPATH (terminal) $ export PYTHONPATH=/Applications/Qgis.app/Contents/Resources/python You can add this line to your .bash_profile Then in Python # Import qgis from qgis.core import * ...


2

Depends on how you installed QGIS. I downloaded it from qgis.org and this is where its Python packages are: $ pwd /Applications/QGIS.app/Contents/Resources/python $ python -c "import qgis; print qgis.__author__" Martin Dobias If that's not the same for you, use the find utility to look for core.so.


2

All QGIS 2.x plugins should run with QGIS 2.6 too. It might be that some plugins need an update. You can look under "installed" plugins if the missing plugins are present, but unchecked.


1

Below is a work around method using python and bunch of libraries such as netCDF4, numpy and shapefile. With Anaconda, these library installations are very much easy. The steps of the method are Import WRF ARW output into python, by python netCDF4 library. Query WRF ARW output variable XLAT, XLONG into numpy array of latitude and longitude using python ...


2

Trying to find a solution, I've changed OpenLayers.js file, provided by plugin authors (which had 'Release 2.11' version in his body and was placed at ~/.qgis2/python/plugins/openlayers_plugin/weblayers/html folder in my system) to last 2.13.1 version from official OpenLayers site (pay attention, 2.+ version!). Just download the archive, extract to ...


0

I just noticed that you missed to set the QGIS installation path, so no provider may be loaded properly and probably this is the root of the problem. Try to change your script as follow: def main(): ## second argument (GUI Enabled) may be False ## if you do not need of GUI stuff QgsApplication([], False) ## installation path for Linux: ...


2

Turn On-the-fly-reprojection OFF and see if the layers still align. If not, save one layer to the CRS of the other using Save As ... under a different filename. Clipping does not work if the layers have different CRS.


1

Try to copy your shapefile into a new one with ogr2ogr and see if that helps. This QGIS issue is about phantom features http://hub.qgis.org/issues/11007. However, the problems described in the ticket appeared when opening shapefiles which were saved by QGIS with another program and not with QGIS itself. It will not hurt to try, though.


4

You can use QGIS' Delimited Text Layer support to add the layer to the map, at which point you can right-click the layer and select 'Save As...' to convert to Shapefile or other supported formats.


4

The "Phantom" feature likely is an invalid one, you should try to make valid it. To fix the feature you can: use the Check Geometry tool (Vector->Geometry tools->Check Geometry Validity). This allows you to find invalid geometries. In this case you have to fix the feature manually by editing it. use the Processing LWGEOM plugin: ...


0

there is a contour-plugin, which you can load via plugin-manager. additional infos here: https://github.com/ccrook/QGIS-Contour-Plugin


1

In this case, you need to know exact CRS your XY data represents. For that use reference data such as imaginery, aereal photography and compare XY data with known locations. For this you can use pluggin coordinates capture is useful. Please refer when using Datum transformations to parameters values, as @Gerardo Jimenez pointed out: ...


3

Other than tile size, as noted by @Irssvt, you can also set some timeout and tile retry parameters. Default timeout per connection is in Settings->Options->network->Timeout for network requests Retry in case of timeout is in Settings->Options->network->Max retry in case of tile request errors. I coded the last retry parameters in QGIS, ...


1

The CRS layer that you loaded in QGIS is WGS84 (geographic system) and you are setting a grid interval in meters, try to enable 'on the fly' CRS transformation and setting a proper projected CRS (i.e EPSG:32633). Take a look at Project properties dialog to do it:


2

Sometime that could occurs with slow connection. You could try to set a tile size for your WMS layer. Change Tile size (e.g 256x256) in WMS Connecition dialog and you see if it works for you: Sometime it helped me for large compositions. Hope this helps.


2

I use GPX format to transfer data from and to Basecamp. The older version I use can also export csv, and import kml and csv. But since I use GPX for export to and from the GPS unit too, I prefer that format for all exchange. You can however not use the Garmin based .img files inside QGIS.


2

I finally managed to fix it on my own, thx anyway ;) The trick is to leave interval units as is: Maps units.


1

If the Reference System for the shape is equal, you can use "intersect" tool (vector>geoprocessing tools>intersect). The vector result have, in the attribute table, the values of two vector that you have processed (wetland areas and boundary).


0

Seems like the settings are not stored correctly. Here's the bug report for future reference http://hub.qgis.org/issues/11713


0

Ok, I found where was the problem. Of course, you have to specify which kind of protocol to use, so the correct syntax was: protocol: new OpenLayers.Protocol.HTTP({...})


0

Found what was the problem. Following that example, I thought that that syntax was referring to properties inside OpenLayers. Instead it wasn't. Where you have to indicate the style, you have to put the name of the namedLayer of your sld, like so: var format = new OpenLayers.Format.SLD(); OpenLayers.Request.GET({ url: 'style/roadsStyle.xml', ...


1

THe short answer is: I can;t see a way. However, changing attributes on a feature is time consuming at times (I have have a hard time figuring out why it happens). Thus, this should speed up your code a bit: pr.addAttributes( [QgsField(aName, QVariant.Double) ] ) attrs={} #------ # Add Values to Triangle Features in Values ...


2

In GRASS GIS, you can use r.thin for this task: The code implements the thinning algorithm described in "Analysis of Thinning Algorithms Using Mathematical Morphology" by Ben-Kwei Jang and Ronlad T. Chin in Transactions on Pattern Analysis and Machine Intelligence, vol. 12, No. 6, June 1990, along with further subsequent improvements. In QGIS, you can ...


0

In the end that's what I did - ripped some code out. Got the coordinates that I needed and then had to play around with the json job done. I got the javascript from here. http://blog.sallarp.com/geojson-google-maps-editor.html


1

With ArcGIS Spatial analyst, you can use the "thin" tool. Their algorithm is described in Zhan, Cixiang, 1993, A Hybrid Line Thinning Approach, Proceedings Auto-Carto 11, Minneapolis , pp. 396-405 As a remark, if you are interested in the process, you can also have a look at the skeletonization process in mathematical morphology. I don't know about a ...


0

Please consider to use v.net.path - finds shortest path on vector network or v.net.alloc - allocates subnets for nearest centers. See also the list of available vector network algorithms. The v.distance command will find the shortest direct distance but you likely want to follow the network in order to obtain more realistic distances.


0

I would suggest taking a look at the ArcScan toolbar if you are using ArcGIS. It has a range of functions in addition to Raster vectorisation which I think should help. Specifically the Raster Cleanup tools such as erosion and dilation which will make your lines thinner. Also check out raster snapping as that may also be useful. The image below is from the ...


4

You can multiply the value by 100 in the column definition and then add the % signs in the legend format as shown here:


0

loaded plugins and their instance are available in the dict qgis.utils.plugins you can manage load and unload with other methods in qgis.utils (do help(qgis.utils) in pythonconsole to show static methods available) this is only the base to solve you problem, you should manage check if running or not using some method in your plugin, or you can check if ...


1

similar to .area(), you can use .length() . For a polygon it yields the perimeter. perimeter=feature.geometry().length()


0

There were some issues with QGIS 2.6 crashing with old projects and the print composer: http://hub.qgis.org/issues/10756 https://hub.qgis.org/issues/11685 You can try the latest dev build, which has some bugs fixed, or wait until a bugfix release 2.6.1 is released. Creating a new project from scratch should be save.


0

The solution for my problem was the Nearest Neighbor Join Plugin.


1

You might have installed the TileMapScaleLevels plugin which forces the use of scales fitting to Google or Openstreetmap tiles. Either deinstall the plugin, or deactivate the scaling inside the plugin.


2

The shapefile you provided seems to be valid, and the projection in the prj files states (if im not mistaken) that your coordinates of each vertex are tied to WGS84 (EPSG:4326) Using ogr2ogr PGDump driver you can translate your shapefile to a sql querry that can be used to insert data into the database: If you are in Windows you can open the console with ...


0

The CRS data you report looks rather broken, with the k factor value stored in other parameters where it does not belong. For reprojecting rasters, you have to use Raster-> Projections -> Warp. Reprojection using Save As only works for vector data.


2

3D is not (yet) implemented in QGIS, but you can store the height in an attribute table field and create a 3D output manually with ogr2ogr -z_field fieldname outside QGIS. See Is it possible to create 3D dxf with OGR? for an example. This is rather 2.5D, because all vertices of a line must have the same elevation (as contours have). In QGIS, you could use ...


1

This is a bit of a late answer, but I thought it was worth contributing. As a polyline is just a series of points you should be able to obtain the Mean value you want by converting the Polyline nodes into points by going Vector > Geometry Tools > Extract Nodes... You can then extract the underlying Raster values for each of these points by using the Point ...


0

You can use Explode Lines in the Processing toolbox to turn each segment into an individual line. Have a look here: Simple automated way to split all lines in layer at vertices using QGIS? You can then open the attribute table of the layer with the newly split lines and use the field calculator to calculate the length into a new attribute with the... ...



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