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2

Instead of a marker you can generate a buffer, setting each category (metro, tam and bus) to a numeric field (1000, 750 and 500). Then run the following queries: SELECT cartodb_id, ST_Transform( ST_Buffer(the_geom::geography, 1000)::geometry ,3857 ) AS the_geom_webmercator FROM table_name WHERE field_name ilike 'metro'; SELECT ...


0

Unfortunately, No. There is no option to create a buffer for grid coordinate in print composer. It will be a good idea if this option can be added into QGIS. You can request such as option at QGIS github if you like.


0

Here is a script that would achieve it: import arcpy import os arcpy.env.workspace = r"D:\Test\Data_Points" Buffers = arcpy.ListFeatureClasses() out = r'D:\Test\data.gdb' for buff in Buffers: arcpy.Buffer_analysis(buff, os.path.join(out,buff[:-4] + '_buffer'), '20 kilometers') print 'done' This script takes all shapefiles from directory, buffers ...


0

I'm not sure weather you want to base the buffer off of each line or each corner. Here is the Polygon to Line tool that may be of use to you in this scenario. The result will give you some attributes of Left_FID and Right_FID which may be helpful if you are trying to classify each side. If you want to base a buffer off of the corners, you can use THIS ...


10

You haven't selected the feature, you used the Identify tool. The Select tool icon 2 over to the right in your toolbars


3

You aren't specifying a name for your output shapefile. arcpy is treating out as a file and appending ".shp" for you. You want a unique name for each output so that it isn't overwritten each loop. import os Buffers = ['JF1','JF2','JF3','FF','FB'] # This is a workspace env.workspace = r"C:\Mydirectory" # This is present in the workspace network = ...


1

Its fairly easy with a bit of spherical geometry to work out the exact coordinates of a 50km circle centred at any lat-long coordinate. So you don't really need to use a buffer algorithm. On a sphere, every 50km circle is the same, just shifted to a new centre. So compute the coordinates for a 50km circle at the North pole (easy) and then apply a rotation ...


2

There's a lot of things to say here. First, there is no really one projected coordinate system which can cover the whole world without any distortion. Secondly, the units of WGS84 is degrees, so you won't be able to compute buffers in kilometers accurately. In my opinion, the best option is to use the geography type in PostGIS as explained here: What is ...


0

The way to do it without plugins is use Batch Processing from Processing toolbox. Find Fixed distance buffer algorithm, and execute is as batch process (right click --> Execute is as batch process). In the batch processing window you can do different settings on different parameters (one layer - different distances, same distance - different layers etc.). ...


2

Simply overlay a reclassified focal mean or distance grid of the polygon indicator. The focal mean requires a circular neighborhood w. Here is a way to create it in terms of the radius, 20. It starts with constant values (line 4). Values beyond the desired radius are zeroed out (line 5). The result is normalized to sum to unity (line 6). radius <- ...


0

I got this error message as well but continued to fill in the TYPE and DISTANCE in the box below the Snap Environment and it worked despite the error message. A bug perhaps?


4

Some simple raster arithmetic should sort this out for you. First make a raster where its NA anywhere except where the original was equal to 2: > rp2 = rp ; rp2[rp2[]!=2]=NA > plot(rp2) Now we can buffer that to 20m: > rp2b = buffer(rp2, 20) > plot(rp2b) Now the ring of the buffer is where rp2 is NA and rp2b is not NA: > rbuff = ...


4

You can't create a buffer with the buffer distances set manually and also by a field in the same step. The simplest solution is the one you're already using in your screenshots: adding the 5m buffer after you've created the others, then merging the two buffer layers. You just need to change a setting in the Buffer tool to create the type of buffer you want ...



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