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ArcWeb Services - Address Finder -Reverse Geocoding
SPC UTILITIES The State Plane Coordinate system provides coordinates on a flat grid for easy computation while maintaining a difference between geodetic and grid distance of one part in 10,000 or better. The State Plane Coordinate system divides the U.S. into a hundred or more distinct grid surfaces (Zones). Do not mix coordinates from one Zone with that in another.
Update 2/9/09: John Palatiello shared this proposal with National Geospatial Advisory Committee (NGAC) last week. Do read the author’s note that explains this proposal has not been submitted to anyone, nor does it have any endorsements. You can learn more about the NGAC meeting in tomorrow’s podcast. —- update 2/2/09————- Update 2/2/09: ESRI has added a “comments” e-mail address to its Building a National GIS website. You can submit comments to: email@example.com. Update 6: ESRI Invites Support for GIS for the Nation as Part of
The Carbon Portal :: Open-Geospatial .NET Community
Robert De Sawal U.S.GeologicalSurvey Denver,Colorado 80225 , Digital Elevation Data and Gis
John H. Porter
The great thing about geographic information systems is that data from different sources can be juxtaposed, according to the way that each is related to the suface of the planet -- and new information emerges about possible realtionships. This is made possible by spatial referencing systems such as Latitude and Longitude or projected coordinate systems. Software is getting better at aligning images and layers that are referenced in different coordinate systems, nevertheless we often encounter problems getting layers to line up as they should. This document provides some tips for troubleshooting and fixing alignment problems with spatial data. Topics Covered in this Document Working with Coordinate Systems
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GIS Cookbook: Recipe - Joining a table Keywords: Tables, joining, relates, sorting, data analysisCategory: Data AnalysisSoftware: ArcGIS 8/9.x Problem: I have information in a table that I would like to join to a point, polygon or line layer. Description: Often times, the information you want to display or analyze within GIS is in two different places or formats. Often you will have a map of a standard area, like the counties in a state or the states of a country, and you will want to add external data to them so you can look at that external data in a spatial context. In this recipe we will look at how to join data to a shapefile. Scenario: Ever since the work of John Snow and his mapping of Cholera cases, mapping cases and frequencies of diseases can help to find sources and cures.
Hands On articles build skills These tutorials demonstrate how GIS can help measure areas of coverage, response times, slope, and other factors. A model is a set of rules or procedures for representing a phenomenon or predicting an outcome. Mike Price has written a series of articles that show how to construct networking models using the ArcGIS Network Analyst and ArcGIS Spatial Analyst extensions. Mapping and Modeling Tutorials