How to encode positional data quality information. Builds on units.xsd to encode
the data needed to describe the positional accuracy of coordinate operations.
Copyright (c) 2002-2005 OGC, All Rights Reserved. For conditions, see OGC Software Notice
http://www.opengeospatial.org/about/?page=ipr
This schema encodes the Data Quality (DQ) package of the extended UML Model for OGC Abstract
Specification Topic 2: Spatial Referencing by Coordinates. That UML model is adapted from ISO
19111 - Spatial referencing by coordinates, as described in Annex C of Topic 2.
Caution: The CRS package in GML 3.1 and GML 3.1.1 is preliminary, and is expected to undergo
some modifications that are not backward compatible during the development of GML 3.2 (ISO
19136). The GML 3.2 package will implement the model described in the revised version of ISO
19111.
Position error estimate (or accuracy) data.
A description of the position accuracy parameter(s) provided.
Closeness of reported coordinate values to values accepted as or being true.
Closeness of the relative positions of two or more positions to their
respective relative positions accepted as or being true.
A quantitative result defined by the evaluation procedure used, and identified
by the measureDescription.
Error estimate covariance matrix.
Ordered sequence of units of measure, corresponding to the row and
column index numbers of the covariance matrix, starting with row and column 1 and
ending with row/column N. Each unit of measure is for the ordinate reflected in the
relevant row and column of the covariance matrix.
Unordered set of elements in this covariance matrix. Because the
covariance matrix is symmetrical, only the elements in the upper or lower diagonal
part (including the main diagonal) of the matrix need to be specified. Any zero
valued covariance elements can be omitted.
An element of a covariance matrix.
Row number of this covariance element value.
Column number of this covariance element value.
Value of covariance matrix element.