12 October 2006

ArcGIS 9.2 - Geodatabase to Double Precision

ArcGIS 9.1 did not support double-precision in personal geodatabases nor does the common shapefile. Now in ArcGIS 9.2 it has returned to ESRI.

"The number of significant digits used to store numbers, particularly coordinate values. Precision is important for accurate feature representation, analysis, and mapping."

"The level of coordinate exactness based on the possible number of significant digits that can be stored for each coordinate. Datasets can be stored in either single or double precision. Double-precision geometries store up to 15 significant digits per coordinate (typically 13 to 14 significant digits), retaining the accuracy of much less than 1 meter at a global extent."

ESRI 9.2 Products
Double Precision—The entire GIS stack (ArcGIS Desktop, ArcGIS Engine, ArcGIS Server, the geodatabase, and ArcSDE) now stores and processes data using double-precision mathematics (technically 53 bits). This allows a single spatial domain to be used for the whole globe, which greatly simplifies the creation and definition of spatial datasets in a geodatabase.

Now we can load in our Arc/Info Coverages into Geodatabases without losing what was Double-Precision

ArcMap Editors in the ArcGIS versions (8 - 9.1) notice that there is a shift in data when using the editing tools,editor menu - clipping, intersecting etc. This is because it uses the single precision of the data frame rather than that of your dataset.
Source: Data Shift

So the question is now is the DATA FRAME now in Double-Precision??

notice the page is missing on the ArcGIS 9.2 online draft? why?

other links: