Latest Contributions by NeilAyres

‎07-31-2013

Curtis Price published a python script to do this in the python forum. Do a search for it.

‎07-31-2013

Why not just project the data into UTM or something.

‎07-31-2013

I would start with a simple bit of trig. Find the distance you have to buffer the pit outline polygon at an angle of 30deg. Like dist = depth of pit / Tan(30). This distance would be your input for the buffer function. Input this as a negative value to buffer the poly inwards. Then you can use these with elevations to build your tins to calc volumes etc. Cheers, Neil

‎06-12-2013

You don't say here what version you are on. I always think it wise when working out a workflow to do it "by hand" ie in ArcMap / Catalog using the tools first, before trying to automate it with modelbuilder or python scripting. Intersect is there in the tool box. Add field by opening the attribute table and add the required fields. Not sure why you need to then export these to a separate table. The centroid can be added to the attributes by using "Calculate Geometry". Add 2 more fields CentX, CentY, for each click on the column header, right click and select "Calculate Geometry". By now you should have everything in the feature class that you need. Poly to Point if you need it. If you want to go out to CAD, I think you will need the data interop extension. Cheers and good luck, Neil

‎06-11-2013

Ahm.. Gentlemen, in the code above I still do not see you doing this - myPtGeometry = arcpy.PointGeometry(myPt, sr) I believe that without this, the select and any other geometry method will not work. Yes, the object has properties (X, Y etc etc) and it looks like a point, but its not quite what it seems. N

‎06-11-2013

When creating the PointGeometry object, include the spatial reference of the coordinate that you are creating. Normally I do this from the sr of a another similar fc using the Describe object. Cheers and good luck, Neil

‎05-16-2013

To get this thread back on track.... I have been fiddling with AGOL for a few weeks now. Got my subscription & points etc etc. Just me at the moment experimenting with different layer types and stuff. And, yes, I am disappointed. The available symbologies is very poor (even a simple compound line style doesn't work). Raster imagery like geophysics with a nice colour ramp.... Half the colour spectrem vanishes... No prioritized symbols And yes, I would like labels. And also yes, you can do this if you publish as a tiled map service and not a feature service, but watch out, even a simple polygon with a name in the middle will turn into a map image of XX Gb, say goodbye to those expensive credits... Was at a local esri conference last week. Gave the man from esri a hard time over AGOL. At the moment its designed for users that want to use a standard base map on which to plot their 15 squirrel locations... Not someone with some fairly large and diverse datasets. Will keep trying though. Perhaps the AGOL team can inform us of where / what improvements are coming along. No squirrels were harmed when typing this post. Cheers, Neil

‎04-25-2013

Dare I say it, but back in the day with workstation and aml, you could list and change the order of drawing elements in the map. Was very useful.

‎04-25-2013

Yes, I agree. The time slider is also very useful for visualising other sequenced variables. It should be opened up to include not only date/time based data but actually any number sequence in the data. This applies also to the variable display settings which currently restrict it to only dates/times. Thanks, Neil

‎04-11-2013

I have just started with AGOL. Got my account sorted a few days ago. I have started very slooowly. I opened a new ArcGIS mxd, loaded a fc with 2 polygons in it. Set the symbology to a hollow fill with a blue / yellow outline. Also set a label with the name of the polygon. Signed in, did all the checking etc and clicked publish. When I go to AGOL and look at my content, the symbology is gone to be replaced with a semi-transparent grey fill with a thick black outline. Also no label. Am I mistaken to think that the symbology of the layer uploaded should be maintained? Or does all the symbology have to be set within AGOL. What about symbol quantities (like analytical values for samples), is this all lost? Thanks in advance, Neil

‎02-07-2013

Chris, Okay, I think I get it. I now understand what you were pointing out. Obvious really. So the "Polygon" build has no prior knowledge of what these coordinates represent, and uses some default resolutions. Thanks again for all your hard work. Cheers, N

‎02-07-2013

I have noticed in the past, when using a feature class as a "template". ie Copy it, delete all the features out of it, when re-populate it with new stuff. The extent somehow still reflects the old stuff. So, I would also love to know how to do this for F & P gdb's. Cheers Neil

‎02-05-2013

Chris, regardless of the slight difference in code, the "old" way has worked for ages. The InsertCursor is pointing at a newly created Fc inside a Fd, so seems carry with it all those good things defined by the Fd. These polygons are being created in a GCS and are quite small. About 800m by 300m in UTM projected space. Approx 0.007 of a degree and less. So, you were correct that some rounding / resolution issue was the problem with the da.InsertCursor way. Its just that the da.InsertCursor isn't "aware" of the spatial resolution / crs of the feature it is inserting into. The old InsertCursor plainly was! Cheers, N

‎01-31-2013

Chris, thanks. That did it. Now the output from both code blocks is exactly the same. Does seem odd though that the "old" way doesn't require the sr to be specifically referenced. The output, btw, is a fc inside an fd in a geodb. Perhaps one could update the help stuff to make this more explicit. Cheers and have a nice day and all that. Neil

‎01-30-2013

I have sucessfully used the old style InsertCursor to build lots of different geometries. But today, I decided to have a look at the new da.InsertCursor and all those "SHAPE@" tokens. Firstly, the geometry points are coming from a table in access. Generally each polygon has 4 records. I read these into a python dictionary of the form - [Key] : [(x1, y1), (x2, y2), (x3, y3), (x4, y4), (x1, y1)] ie my key is the polygon name and this points to a list of tuple pairs. Note that I have repeated the first coord at the end so that the polygon closes. So each of these code blocks is reading exactly the same data dictionary (PolyData). Firstly, the old style way of doing it : OutCur = arcpy.InsertCursor(os.path.join(OutPath, OutPoly)) for k in PolyData: v = PolyData array = arcpy.Array() # print k, len(v) for xy in v: point = arcpy.Point() point.X = xy[0] point.Y = xy[1] array.add(point) FcPoly = OutCur.newRow() FcPoly.setValue("PMLNo", k) FcPoly.shape = array OutCur.insertRow(FcPoly) del OutCur Then the new da way: OutCur = arcpy.da.InsertCursor(os.path.join(OutPath, OutPoly + "2"), ["PMLNo", "SHAPE@"]) for k in PolyData: v = PolyData array = arcpy.Array() # print k, len(v) for xy in v: point = arcpy.Point() point.X = xy[0] point.Y = xy[1] array.add(point) polygon = arcpy.Polygon(array) data = [k, polygon] OutCur.insertRow(data) del OutCur Sadly the da way gives me some decidely odd looking (and non-existant) geometries. Have a look at the screen grab. The red outlines are the output of the old way. The label in the middle is the polygon name. The green outlines are the da way output. Not only has the geometry gone from a rhomboid to a triangle, but even the corners are in a different place(?). A bigger worry is that most of this second polygon layer has null geometry. Note the lack of other green polygons, where the red ones are. Can someone please advise me on what I am doing wrong with the da InsertCursor way of doing things. Thanks in advance, Neil

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My Ideas

Latest Contributions by NeilAyres

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Layer symbology after upload

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Re: Problems constructing geometry using da.InsertCursor

Re: Problems constructing geometry using da.InsertCursor

Problems constructing geometry using da.InsertCursor

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