New answers tagged

0

I would first extract the related values from the raster based on empirical point data with extract {raster} and then compare the simulated data points with the empirical data points using a confusion matrix with table {base} and confusionMatrix {caret}. More or less pseudocode: library(raster) p_sim <- extract(raster, p_emp) ### Confusion matrix ...


0

if you can't enable editing then maybe your data is saved as geojson or kml, you can save it as a shapefile (shp) with QGIS and load it again this way the edits can be enabled from the tool bar ( the little pen ) and you can add the data you wanted.


0

ST_Dump will do it.... change DESC to ASC to get the other end. This example sorts the geometry by ST_Y: SELECT ST_Astext(geom) FROM ST_Dump('MULTIPOINT(1673118.56314624 5778263.30559826,1672914.41092247 5778129.131443,1672384.7731665 5778105.44570288,1673513.70724225 5778525.74090022)') Order By ST_Y(geom) DESC Limit 1 Or this example filters by path #:...


0

You can use the first coordinates to create a new point: ST_MakePoint(ST_XMin(your geometry),ST_YMin(your geometry))


0

Use the buffer tool to create your 500m buffer polygons. Then use the intersect tool with your buffer layer as the only input. The output from the tool will be all the buffers that are overlapping with attribute information for each of the polygons that can be used to link back to your original plots.


0

OK there are a couple of options for you. Obviously business name matching won't work, spatial joins will be unreliable, and address formatting isn't the same. One possible solution could be rubber sheeting (http://desktop.arcgis.com/en/arcmap/10.3/manage-data/editing-existing-features/about-spatial-adjustment-rubbersheeting.htm). Rubber sheeting is ...


0

The QGIS NNJoin plugin should be able to help you, but it will generate a new point layer and not update your existing point layer. See https://plugins.qgis.org/plugins/NNJoin/ and http://arken.nmbu.no/~havatv/gis/qgisplugins/NNJoin/. Use your point layer as "Input vector layer" and your line layer as "Join vector layer". The result is a new point vector ...


3

Point sampling tool works perfectly if the spatial reference (projection) of the raster data and the point shapefile are same. Working with different projections for the raster(s) and shapefile data will create a shapefile with empty column of raster (Null) values. You need to change the projection of point shapefile to be similar to the raster data to get ...


0

This method should clean up the point layer many points per polygon: Use Feature To Point to create new centroid point layer representing each polygon Use Generate Near Table to identify the nearest point layer to the new polygon/centroid point layer (this will give you the fid value of each layer) Join near table result back to original point layer (using ...


1

I can't comment because of status credits, but in response to You could just calculate and export the centroid of the polygon/building footprint to give you one point. It is to be weary that centroids don't necessarily fall within polygons (buildings), such as polygons with donuts (in your instance a building with an atrium). http://support.esri....


2

I suggest using the Delete Identical Tool. However, the precise application depends on both your data and the purpose of your task. In case your point features share the same location (you want to delete duplicates), use the Delete Identical Tool and select the "Shape" field. In case your point features don't share the same location and you want to ...


1

You could just calculate and export the centroid of the polygon/building footprint to give you one point.


0

There is no good solution for sharing symbols with SVGs yet. Here's a recent discussion on the mailing list and the resulting feature request. For now, you have to manually make sure to copy the SVG and configure QGIS to find it on the other PC.


0

Have you tried st_intersects? Below is a statement using a combination of st_intersects and st_buffer... st_buffer is providing for some error in alignment between the valve and the tube in my sample data. If you really want it precise then remove the st_buffer function. select v.name from valves as v where st_intersects(v.geom ,st_buffer((select t.geom ...


1

You can create a 0.5m buffer zone and then use the select by location tool (top toolbar under Selection). At the target layer you select the buffer and at the source layer prompt the other layer. At the spatial selection method you can select "are within the source layer feature".


-2

What about a buffer ? Does it works ? It's a better way to create that. You'll see all the points that you want.


2

Perhaps the easiest way is using the near tool if you have the license. If you don't have the license then there are ways to code this functionality. Or you can possibly run a buffer of .5 m to create small polygons and then do a spatial join between the buffer and the point layers. Then you can select the points that share the same buffer feature ID.


0

Interpolation (which one of the methods of interpolation? there are a lot of them) is a grid of VALUES (not number of points) of the points you have. On the other hand Heat Map is just a density grid (only the density of points per area unit that you set). Interpretation of the Heat Map is easy: red areas have higher density of buildings per area unit. (We ...


2

This can be done in Qgis by using "rule based" symbology with two levels of settings. To safe you a bit of work you go to "symbology" - "categories" first and classify your data on the column qualifier that defines your shapes. But donĀ“t set any shapes yet, its just a work in progress step and will be dismissed in the end. Then you go to "rule based". You ...


2

In your case, it is not necessary to create polygon buffers for your points. The raster::extract function has a buffer argument that will do exactly what you are after. library(raster) r <- raster(ncol=36, nrow=18) r[] <- 1:ncell(r) xy <- SpatialPoints(cbind(-50, seq(-80, 80, by=20))) extract(r, xy, buffer=1000000, fun=mean) For future ...


4

One possible solution is to use St_ClusterWithin. This creates geometry collections of all the geometries that are within a distince, d, of each other, and takes the form ST_ClusterWithin(geom, d). Start by using ST_ClusterWithin. Wrap this function in unnest and ST_CollectionExtract which takes a GeometryCollection and a number, in this case 1, points, ...


0

It sounds like you have multiple points stacked on top of each other. Try dragging a selection box over a point and check the attribute table to see how many features you have selected. If it really is duplicating then you might want to update QGIS to a newer version (2.14) and try it again.


1

You can convert these points to raster by FeatureToRaster and set cell size to grid width, Then use RasteToPolygon convert raster to grid polygon.



Top 50 recent answers are included