MC5
  • Member for 9 years, 10 months
  • Last seen more than 2 years ago
  • Madison, WI
Which projection is best for mapping the contiguous United States?
24 votes

The Albers equal area conic is the typical projection for historical USGS maps of the lower 48, it being a general-purpose low-distortion compromise for mid-latitude short and wide extents. As a ...

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Spatial reference for dummies?
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16 votes

Personally, for the cliff's notes I find the ESRI ArcGIS desktop software help system useful, and and also the ESRI book Understanding Map Projections, its first 30 pages are not unlike a short ...

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ArcGIS API for JavaScript - error in Dojo parser.parse()
Accepted answer
8 votes

Can't have lang="en" attribute on the opening HTML tag of the page. Found that gem way down a long ESRI forum post (reply #8) that I'd been too impatient to read before.

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Need File Geodatabase (*.gdb) read/write support in QGIS?
4 votes

I see this: and my options in the OSGeo4W Setup ('advanced install') that are probably relevant were:

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ArcObjects - find nearest feature to a point - has to be FAST
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4 votes

Here I go answering my own question. It turns out that a brute-force "spatial query a search radius, loop over every feature in it, measure distance to each" approach is faster than I expected. This ...

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Choosing File Geodatabase (*.gdb), Personal Geodatabase (*.mdb) or shapefile format?
4 votes

if you want full-blown geodatabase capability (Coded Value Domains, Relationship Classes, Topologies, Geometric Networks, etc blah blah, without the complexity or admin overhead of relational ...

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Add feature layer to display with in a script tool for desktop mapping 'App'
4 votes

Let me paraphrase the problem to see if I get it - ArcPy.Mapping.AddLayer() will add a layer to the data frame if the script is run from the python window, but not if it is run from a script tool? If ...

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Shapefiles are not being added to MXD using ArcPy?
3 votes

I tested your snippet (at least in ArcMap's interactive Python window) and got the same error until I changed the formatting of the string parameter to the Layer() method. Either single or double ...

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What is the difference between ST_GEOMETRY and WKT?
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2 votes

WKT is a text interchange format (Wikipedia) (PostGIS), and if you use PostGIS, you might use it like I do occasionally in SQL queries, to get a quick non-visual check on the geometry - see the ...

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Generate GeoJSON from MongDB Query
2 votes

there's a small issue with that JSON. First, try jsonlint on the whole thing, you'll see that it complains about the format of the 3 "_id" properties. If you replace those with for example 123, 456, ...

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Setting permission to user for web editing using ArcGIS silverlight API
2 votes

For apps I've been involved with, we use secured Feature Services (with the accounts used to secure the services coming from Active Directory - these are different than the accounts used to secure the ...

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How to check active users of ArcGIS 10.2 Floating License with python 2.7?
2 votes

At the risk of being vague: ArcGIS (as of 10.1) uses FlexNet Publisher License Manager v11.9. See the License Manager Reference Guide. There doesn't appear to be a programmatic API, though there is an ...

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Change in ArcGIS locator service causing error
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2 votes

It appears ESRI has been retiring their old free geocoding services, such as the one at http://tasks.arcgisonline.com/ArcGIS/rest/services/Locators/TA_Streets_US/GeocodeServer, as described if you ...

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Why do points shift when reprojected from WGS84 to a state plane coordinate?
Accepted answer
2 votes

It may be a lack of datum transformation in your projection operation. Your symptom sounds familiar. It is a common problem here in Wisconsin - GPS uses the WGS84 datum, but our state system uses ...

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Autoincrement field when New Feature added
2 votes

if the data are in ArcSDE, you could use the RDBMS platform, whether it be SQLServer, Oracle, etc, to use a sequence to populate an ID column with a unique auto-incremented integer identifier. if you ...

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ArcGIS 10.1 - c# custom geoprocessing function tool - how to populate a polyline output parameter?
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2 votes

If it weren't for that apparent bug casting a GPLine to IGPLine2, I would just return the polyline geometry in a GPLine output parameter. Whatever. There is thankfully newish stuff in ArcObjects and ...

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Is there a source for leaf-off aerial imagery?
2 votes

Nationally, you could check the list of programs at http://www.ndop.gov/maintenance.html or http://pubs.usgs.gov/fs/2009/3055/pdf/FS2009-3055.pdf. At least 2 programs that fly leaf-off are listed. ...

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Creating MapTips programmatically for programmatically-created KML layer using ArcGIS API for Silverlight?
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2 votes

KmlLayer is alien to me, but I see it has a MapTip property same as FeatureLayer. Here's what we've got for FeatureLayers. These two lines are present in my main MapPage.xaml.cs in an event handler ...

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Embedding slippy map in Access form
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2 votes

i apologize if this ends up being too handwavey to be useful, but here goes. Back in the day we'd make Access GIS apps using the ESRI MapObjects map control. Sounds similar to you. We also would use a ...

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How do I convert a GPX to SHP with extended properties?
1 votes

if you don't mind a manual, mousing-around process in QGIS, try this: click the Add Vector Layer button, select 'File' as the Source type, and browse to your GPX. This adds layer(s) from your GPX to ...

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Is a photo of an infrared slide taken in a light box a digital Infrared image?
Accepted answer
1 votes

leaving geometric considerations aside, speaking spectrally, it seems to me that such a digital photo would be a product of the radiance curve (brightness vs wavelength) of the lamp in the box, and ...

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How to perform relational queries against an ArcSDE geodatabase using the ArcGIS API for JavaScript?
1 votes

Since this is an ArcSDE geodatabase, consider using database views for queries that do not include spatial columns, or spatial views for those that do, to join related tables via their FKs as needed ...

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Which version(s) of ArcGIS API are compatible with ArcGIS 10.2?
Accepted answer
1 votes

based on the ESRI ArcGIS API for Silverlight docs for 3.1 and 3.3, I believe you want 3.2 or newer, Silverlight 5, and Visual Studio 2012 or newer to build apps to hit 10.2 servers.

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How to fill gaps in a multipart polyline
1 votes

KK was quick on the trigger while I was in progress with similar. KK's answer assumes each part is linear (consisting only of a start and end vertex). This answer is similar but does not make that ...

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How to populate M values for an existing x,y,m route layer in ArcGIS 10?
Accepted answer
1 votes

Yep, that 'possibility' I cited in my last paragraph was (mostly) the ticket. I added fmeas and tmeas columns, calc'ed fmeas = 0, tmeas = shape_length, and used those two columns in the 'CreateRoutes' ...

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Coordinate conversion - Lat Long to State Plane, ArcServer-Silverlight
1 votes

You can use the ArcGIS Server REST API out-of-the-box Geometry Service, which has a Project operation, to project a coordinate pair, and then create a graphic from it. The Geometry Service is included ...

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Lat/Long to XY conversion with Geometry Service
1 votes

See my answer to your other very similar question for example code using the Silverlight API's GeometryService Project operation.

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How to add Radio Buttons to Python Script tool dialog?
1 votes

Perhaps you want to use an input parameter Data Type of Layer File, and set its MultiValue property to Yes. Your tool's dialog will then allow you to select multiple layer files and add them to a list....

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Using ArcGIS Server SOE to listen for edit events
1 votes

If the layers used by the service are in a DB as your mention of stored procs suggests, and all your logic can be expressed in SQL, you can use DB triggers. We do this routinely with Oracle ArcSDE ...

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How do I start to debug COM error "HRESULT E_FAIL" for TableToGeodatabase geoprocessing tool?
1 votes

I'm wrestling with my own ArcObjects COM errors, here's an idea: put the offending code in a try block, and include a catch {COMException ce}. Then examine ce.ErrorCode. That gets you the 10-digit ...

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