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4

Without your original data, I can't be sure this will work, but I thought it might help you out. I didn't bring it all the way there, this solution still likely needs some level of automation, but might give you a general way forward First, I create some spatial polygons polypoints1 <- matrix(c(1,2,2,1,1,2,2,1,1,2),ncol=2) polypoints2 <- ...


3

I guess your query area Germany does not exist with that name. Using Deutschland and disabeling the timeout returns the data. I zoomed around Heidelberg and ran the query successfully and much quicker, querying the extent of the map canvas.


3

Use a colour scale, getting darker for each additional person buried in a plot. ColorBrewer is a great place to look for good colour schemes. I imagine most would just be one person, but ones that are darker indicate the presence of multiple people. If your problem is how you associate cemetary plots and a table of people buried therein, then you need to ...


3

According to this QGIS Change Log entry for the latest 2.10 "Pisa" release of QGIS, support for true curve features, including circles, was only just added in this latest release. See the "New geometry engine" topic. It requires a datasource like PostGIS that supports true curved geometry types. However, the documentation there is slightly ambiguous. It ...


3

You can try the Sort Tool. It can be used to sort by attribute, or more importantly for you, spatially. It allows you to pick which corner (i.e. upper right) to give priority when sorting.


3

First you have to convert your polygon to lines. Then you can use Generate Near table. With this tool you can create table with few parameters (coordinates, angles) of nearest objects to your input objects. You can get this coordinates and create point layer if you need to visualise that.


2

I can think of two things off the top of my head. If you want to stick with an Add-In, you can use the onLinemethod and simply iterate through the line geometry the user creates and pass those points into an array and convert that to a polygon. The can add segments and finishes by double clicking. Or, another option is to make a script tool. With a ...


2

Yes, it's possible to fill a polygon with symbols on an angle. It cannot be done with Marker symbol type, only with Picture symbol type. Even with Picture it applies to the symbol as a whole, meaning you'd need to symbolize on your rotation field and set each one to the angle you want - the angle cannot be read automatically from a field (so far as I ...


2

I have never worked in QGIS. The R equivalent would be to use gUnion in the rgeos package: http://www.inside-r.org/packages/cran/rgeos/docs/gUnion Here is a reproducible example to demonstrate: library(sp) library(rgeos) #create polygon r1 <- cbind(c(641777, 642290, 642276, 641794), c(7036885, 7036743, 7036154, 7036146)) r2 <- cbind(c(642320, ...


2

Thanks for your feedback. I solved this by creating a second polygon around the entire raster extent, to which I assigned a value of zero. Previously, the shapefile only contained a single polygon, hence the cells outside of it had no value. Thus, the new shapefile and raster contain a value of 7.5 at the polygon and 0 elsewhere. (PS I am relatively new to ...


2

As requested, comment is appended below as an answer: "Also, is Feature To Polygon designed to work on a layer selection? Perhaps export the layer as a standalone feature class with Copy Features (in memory perhaps) and try running the tool that way. If that doesn't solve it, there are some threads here and here that use arcpy.Geometry.cut() for those who ...


2

Take a look at the plug in CADDigitize. It may be helpful. edit : This tool allows the user to draw circles, squares, resctangels, ellipses from many ways.


2

As you have specified that the line from the point can pass in/out of the polygon then I think all you need to do is extract the Envelope of the polygon. You also state in the comment above you are look for an arcpy solution and you have a Basic license level. You can get most of the way with model builder and a sneaky use of the fishnet tool to extract the ...


2

A point inside a polygon canvas = qgis.utils.iface.mapCanvas() aLayer = canvas.layer(0) # or code to select the layer of interest for f in aLayer.getFeatures(): geom = f.geometry() p = geom.pointOnSurface() print p.asPoint() Get Inner Rings canvas = qgis.utils.iface.mapCanvas() aLayer = canvas.layer(0) # or code to select the layer of ...


2

Feature To Polygon will slice polygons by line feature classes when you use the two feature classes as its input. Inputs: Results: If you only want certain polygons sliced by certain lines, use an SQL expression and feature layers to limit your inputs.


2

Intersect will give you polygons representing the overlap. Then you can use Dissolve with a statistic of sum on your value field. Finally, you can Merge/Append back to the original dataset:


1

If you don't want to zoom before around Heidelberg and if you are pretty sure that only one object is called Umweltzone Heidelberg, you can set a quick query like this : key name value Umweltzone Heidelberg in : empty value. This will create only an attribute query, not a geographic query. This kind of query is very quick. <osm-script output="xml" ...


1

To be honest, a python script (if you are familiar with Python) would be the most efficient method of creating your polygons in your use-case. However, if you are not familiar with scripting, then there are a variety of tools that you should investigate in QGIS (e.g. Vector->Research Tools->Vector Grid). You will have to use a crazy combination of ...


1

You could use Zonal Statistics as Table to generate a table with a Unique ID field that can be used to join to the polygon buffer attribute table. The tool takes 1) a dataset that defines the zone (your buffer polygons), 2) a zone field (some unique ID field in the buffer polygons), 3) a raster that contains the values on which to calculate a statistic ...


1

Shapefiles should be converted to file geodatabases for performance and precision and for many options not available with shapefiles. One of the benefits of converting a shapefile to a feature class in a file geodatabase is that you get an automatically calculated area and perimeter length field for your polygons (length for polylines). If you keep it as a ...


1

Since you put GRASS into the tags, here's a solution based on GRASS: First, you need to know exactly what coordinate system the original data is in (as always with GRASS). I see that the *.prj file contains "TRANSVERSE MERCATOR" but it's not one of the standard UTM zones. Since you have not mentioned the EPSG code of this data, here's the proj4 string for ...


1

Sounds like cleaning the geometry up will get you on the road to your non-raster solution ... herewith something of a kludge which does help with fixing bad geometry: # Load the library and problematic data library(rgeos) load("oneImage2_spdf.Rdata") >gIsValid(polysData, reason = T) Error in RGEOSBinTopoFunc(spgeom1, spgeom2, byid, id, drop_lower_td, ...


1

I had the same problem and i tried to solve it with the answers above but it did not work for me. What actually worked is this var polygonLayer = new OpenLayers.Layer.Vector("Polygon"); var polygon = new OpenLayers.Control.DrawFeature(polygonLayer, OpenLayers.Handler.Polygon); map.addControl(polygon); polygon.handler.callbacks.point = function(point){ ...


1

The following python script (which requires ArcGIS 10.1 or later) utilizes arcpy.da to take a shapefile as an input and create a spreadsheet with an entry for each vertex in each polygon present in the .shp (and I believe it works with lower level arcgis licenses). Object and sequence id's tie the points back to a specific position in a specific polygon. ...



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