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8

We have had quite a lot of success doing this in 6 Australian and two South African cities under the banner of GeoRabble. Its About page describes the process for how GeoRabble "self-organizes" and we would be happy to try and help you get one off the ground. Some things that have made GeoRabble successful are: The definition of a GIS Professional being ...


5

You can open layers contained in a project into the current QGIS session by using the Import Layers to Project plugin. This will let you choose which layers you would like to load into your current QGIS session. You could also take a look at the Embed Layers and Groups functionality. This allows you to open layers from a project. It stops you from ...


5

I recognize that a few of these have been covered in other posts, but they are worth re-iterating. Here are my keys to organizing a successful user group: Your professional network. The most important part of a user group is each individuals professional network. You need personal interaction on a professional & educational level. Get the word out ...


4

Use a CASE statement and a sub-query: SELECT foo.category, SUM(ST_Length(foo.the_geom)) as length FROM (SELECT gid, year, the_geom, (CASE WHEN year BETWEEN 2005 AND 2014 THEN "1"; WHEN year BETWEEN 1995 AND 2004 THEN "2"; WHEN year BETWEEN 1985 AND 1994 THEN "3"; WHEN year BETWEEN 1975 AND 1984 THEN "4"; ... ...


4

I suggest you to install Group Stats plugin. Here is a quick tutorial: Search for the Group Stats icon Select the layer in which you have the Codes Select the attribute (in your case Code) Click on Calculate The Count will appear. If you go to preferences you should be able to select only Count avoiding the other parameters to be displayed (this is not ...


4

You can create unique values but based on which polygon the point resides in. Add a unique attribute which is at least 10 times larger than the amount of points to your polygons, and the join this value to your points. Like in your example, the upper polygon would have 100. Join to your points and create unique values that is something like 101 and 102. ...


4

As your polygon example is not convex, I would rather use some "morphological math" tricks. You dilate your polygons so that closeby polygons will touch each others and fill the gaps of your streets, then you erode the block so that the contour is the same as the origin. In practice, you can do it with vectors using the buffer tool. After first positive ...


3

In PostGIS, use ST_Collect to collect your block geometries into one geometry. Then use ST_ConvexHull to get the convex hull, or try ST_ConcaveHull to get a better fit at the cost of more CPU.


3

I think there is more detail required in your question. But maybe you could select the shapes by using a rectangle or polygon, then use the Merge Shapes Tool. Maybe then also add a buffer before that step if you want the final shape to be more contiguous. hth


3

Another tool which might be useful to you is the Linear Directional Mean tool which "Identifies the mean direction, length, and geographic center for a set of lines." It will not identify the clusters of lines, however. You may have to select these out manually first. In your example, I see three major clusters of lines - top, middle, and bottom (with ...


3

You could try Dissolve (Data Management) tool. http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//00170000005n000000 Integrate (Data Management) also shows promise, although I can't find anything about it under ArcGIS 10. Only under 9.3.1. http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?TopicName=integrate_(data_management)


3

how about something like this? it'll get all layers in the TOC... Dim pMxDoc As IMxDocument = TryCast(m_application.Document, IMxDocument) Dim pMap As IMap = pMxDoc.FocusMap Dim pEnumLayer As IEnumLayer = pMap.Layers pEnumLayer.Reset() Dim pLayer As ILayer = pEnumLayer.Next Dim pFLayer As IFeatureLayer = ...


2

As @NathanW pointed out, you are trying to pass your sql_clause to the where_clause parameter. I've found two posts (here and here) that show passing the sql_clause parameter as a tuple (the help also agrees), not a string, so you might want to try the following: sql = (None, 'GROUP BY "INPUT_FID"') with arcpy.da.UpdateCursor("outDistanceSorted", ...


2

this is a sumarize function. You will need to right click on the area field and hit summarize. Then add the value field and sum it. After you complete that you can join that table back to the original data using the id field. NOTE: it is advisable to not use the fid,OID field for your id. Just create a new field and calculate the value from fid into it.


2

What you could do is within a loop - create feature layers out of your points - then do the point near analysis. As a brief example: import arcpy countries = ['CANADA','USA'] arcpy.MakeFeatureLayer_management('PATH_TO_CITIES_FC','cityfc') arcpy.MakeFeatureLayer_management('PATH_TO_CAPITALS_FC','capitalfc') for country in countries: ...


1

here is an alternative to your solution #store field values in a new list newlist=[] with arcpy.da.SearchCursor(fc, ("valueField")) as scursor: for row in scursor: newlist.append(row[0]) #find the boundaries between classes newlist.sort() limits=[0] for j in range(newlist): if (newlist[j+1]-newlist[j])>2.5: ...


1

The Logistics Issue: There are really two things that you need to get a GIS organization started: The network: There is a greater percentage of public sector GIS employees in the workforce right now than private sector. Therefore, attempts to build a GIS network should focus on inclusion of these employees. In my experience, an e-mail list is the most ...


1

Whenever you use an aggregate function with a GROUP BY clause and multiple results are available for the aggregate function, the last of the values is the one that's returned. That's why you're getting "wheat" for the pk_uid 168. What you can do to get the actual Max() value for the correct landuse is use a sorted subquery, and do the GROUP BY in the outer ...


1

While this isn't really a technical question related to this form, I think it is a really good question. How I would start is to use the power of social media. Begin by making a Google Page and Google Group. If you have people/members in your area that you would like to be apart of it, send them join requests. Now you will have some formality, and a ...


1

you could also use Qspatialite in QGIS. The SQL window is just as Mapinfo one. Up to you after to make your SQL request with a groupby command on the wanted column.


1

This should work; it worked for me. This will give you a group layer named by the folder and a layer with the name of the shapefile. I built off what artwork21 posted. import os import arcpy WS = r'c:\test_define' arcpy.env.workspace = "in_memory" mxd = arcpy.mapping.MapDocument(r"c:\test_define\test_python_add2.mxd") df = ...


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you can use this answer by replacing 300 by 600 (the number of seconds in 10 minutes)


1

If TypeOf pMap.Layer(i) Is IGroupLayer Then you could use recursion to go inside of the grouplayers until all groups are searched. A good example was found at esri forums Just copying the recursive part here: Private Function LayerByName(pLayer As ILayer, sName As String) As ILayer Dim pReturnLayer As ILayer Dim pCompositeLayer As ...



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