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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 ...


4

You need to do this in a two-stage process using the Vector->Analysis Tools->Mean Coordinates tool in the second step. This tool will return the mean coordinates for sets of point within a layer if they have a unique ID field. So, if you have a polygon layer which defines your areas, do a spatial join (Vector->Data Management->Join attributes ...


3

QGIS documention actually gives examples (one includes temperature data) using Inverse Distance Weighted and another example using a TIN. be sure to look at "Common problems / things to be aware of" - per the linked page above: 1) Evaluate the sample data. Do this to get an idea on how data are distributed in the area, as this may provide hints on which ...


3

I am not sure if I fully understand the question you are asking, but if you are looking to put the number that is stored in the ID column in the attribute field over the point location on a map you can do two very simple things, label by attribute and make the point 'invisible'. 1) Label based on the attribute column. 2) Change the point symbology to be a ...


2

Using QGIS, Vector -> Reserach Tools -> Polygon from layer extent gives you a polygon that you can use for clipping the other vector data to. There is a GDAL module called gdaltindex that does the same without using other software: gdaltindex N51E007.shp N51E007.hgt creates a bounding polygon for a sample SRTM data file. For a python solution to ...


1

When interpolating points, I tend to personally use Heatmaps (download the Heatmap plugin from Plugins > Manage and Install plugins...). You can then find the option in Raster > Heatmap: I made a simple point layer in the form of a square and ran the Heatmap function. I then set the colouring filter in the Layer Properties: And I get this as a result: ...


1

Please DO NOT use Set CRS for Layer if you want to reproject a vector layer to another CRS. This will corrupt your data, because it does not recalculate any coordinates. Use Rightclick Save As ... under a different file name and different CRS. You better set the layer back to the previous CRS, or delete it and reload a fresh copy.


1

Without more exact knowledge about your source route system and event overlays it is difficult to say exactly what is going on. It would appear that your route is not being created with a starting measure of 0, since negative measures should normally not be created by these tools unless those measures exist on the route. The Create Route tool can generate ...


1

This interaction does not support custom projections. In the code, the private ol.interaction.DragAndDrop.prototype.handleResult_ calls the code below: var readFeatures = this.tryReadFeatures_(format, result); This code itself return format.readFeatures(text) (where format is ol.format.GeoJSON). If custom projections were supported, it would be ...


1

OpenLayers has a GetCentroid function for getting the centre of a polygon if you don't want to bring it in from the database directly: http://dev.openlayers.org/apidocs/files/OpenLayers/Geometry-js.html#OpenLayers.Geometry.getCentroid From there you should just be able to treat the point as a regular point feature. See also this example: ...


1

If I understand your question, you want to be able to change a property on all or some of the features (on separate layers) on the map. From the ol.map object, you can get the layergroup property. This will give you access to all the layers on the map, you can then just do something like: var layers = map.get('layergroup').getLayersArray(); for (var i in ...


1

thanks my friend Chris, he's truly help me resolved the problem... and the anser will be like this.. http://jsfiddle.net/v18kuxgf/ polygonLayer.events.register('featureadded', null, function(event) { var feature = event.feature, geometry = feature.geometry; if (geometry.getArea() ...


1

MMQGIS plugin have your merge funcion... other merge funcion can be found in Processing/gdal Processing/saga but MMGIS works as you aspected


1

You could create a GDALDataset with as many bands as you have raster bands, then copy the data from each of your bands into the corresponding band in the GDALDataset. Here's some example code in C++ (since that's where I'm most familiar with GDAL). //create the dataset const char *filename = "example.tif"; GDALDriver *pDriverTiff = ...


1

You can do this using the "Tabulate Area" Tool (Spatial Analyst Toolbox). You won't need to convert the data because you can use the polygon layer as the "zone" layer (sometimes called the "class" layer) and the raster land cover as the "value" layer. The class/value values will likely be numeric (which may explain why you didn't see any land use types after ...


1

So that was simple. Searching for mapbox.js, I saw that a newer version is out. Using the latest css/.js: <script src='https://api.tiles.mapbox.com/mapbox.js/v2.1.2/mapbox.js'></script> <link href='https://api.tiles.mapbox.com/mapbox.js/v2.1.2/mapbox.css' rel='stylesheet' /> Shows a retina projection.


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In the end I wrote the following script that solved my problem. The script converts raster pixels with a specified value to vector lines. For example the blue pixels (value = 0) are converted to vector lines. There is definitly room to improve the script, as you can see in the result image. The script can be found and edited here. Raster Image Raster ...



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