Any hardcopies utilizing DNR data sets shall clearly indicate their source. If the licensee has modified the data in any way they are obligated to describe the types of modifications they have performed on the hardcopy map. Licensee specifically agrees not to misrepresent DNR data sets, nor to imply that changes they made were approved by DNR.
These data are not to be used for commercial profit.
GIS Processing: B. Stiff, D. Nelson Documentation: D. Nelson and S. Beaverson Quality Control: ISGS Staff, D. Nelson
Data set was DESCRIBED and coverage files listed to determine the feature types present. In this data set, the following feature types were found and checked: polygons, arcs, labels, nodes, and annotation. The presence of spatial indices was also checked.
For PAT and AAT files, each ITEM was checked for the following:
- DOMAIN of allowable values - adherence of values to the DOMAIN - definition of ITEMS - requirement of all UNIQUE values for an item - logic of ITEMS REDEFINED over other ITEMS - length of ITEM name as regards conversion to shape fileBUILD statuses of data sets were checked, as were LABELERRORS and NODEERRORS (where appropriate), and PROJECTION definition.
The presence of a BND file was verified.
The presence and location of TICS were checked.
Polygon and chain-node topology present. There are no dangling arcs. There is one polygon label per polygon, except for universe polygon. Boundary values appropriate for map projection and map units. "Fuzzy" tolerance is suitable for nominal scale. Two arcs in the Chicago region form the eastern boundaries of two irregularly shaped quadrangles. These have a value of 999.999 in .AAT item COORD. There are no attribute values outside the appropriate domains.
Attribute items are in typical ARC/INFO feature class format.
Those requiring additional explanation are:
POLYGON ATTRIBUTES:
MAPNAME - Name of the associated USGS 30' x 60' quadrangle
USGS - USGS map sheet index designation. This is an alphanumeric
combination of degrees north and west with a row column
index applied to each 1 degree by 1 degree area.
ARC ATTRIBUTES:
COORD - The latitude value for east-west arcs or the longitude
value for north-south arcs. Values are in decimal degrees.
COORD is redefined into two smaller fields:
INTEGER - The value of COORD to the left of the decimal.
(The value of COORD rounded down to a whole number.)
DECIMAL - The value of COORD to the right of the decimal.
(The incremental fraction of COORD.)
Q100 - Indicates if arc is also a boundary for a 30' x 60' quad.
0 - arc is not a 30' x 60' quad boundary
2 - arc is a 30' x 60' quad boundary
Q75 - Indicates if arc is also a boundary for a 7.5 minute quad.
0 - arc is not a 7.5 minute quad boundary
2 - arc is a 7.5 minute quad boundary
Q250 - Indicates if arc is also a boundary for a 1 x 2 degree quad.
0 - arc is not a 1 x 2 degree quad boundary
2 - arc is a 1 x 2 degree quad boundary
ANNOTATION ATTRIBUTES:
Each quad is annotated with the quad name.
In no event shall the DNR have any liability whatsoever for payment of any consequential, incidental, indirect, special, or tort damages of any kind, including, but not limited to, any loss of profits arising out of use of or reliance on the geographic data or arising out of the delivery, installation, operation, or support by DNR.
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Illinois Natural Resources Geospatial Data Clearinghouse
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