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Standards and Specifications - NTDB Edition 3
The organizational unit of the National Topographic Data Base (NTDB) is the National Topographic System (NTS), based on
the North American Datum of 1983 (NAD83). Each data set corresponds to one NTS map sheet at the 1:50 000 or 1:250 000 scale.
The metric coordinates of their limits are expressed in rounded integer values. In the metadata files, they are either
expressed in rounded integer values or in truncated integer values. Metric coordinates expressed in real values for each
data file are available on our FTP site.
(HTTP version)
All data comply with the NTDB Standards and Specifications - Edition 3.1
Adobe Acrobat Reader can be downloaded free of charge from the Adobe Web site.
*Important information about the NTDB RR, CH and TO themes.
Standards and Specifications
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Formats |
NTDB Standards and Specifications
This document describes NTDB organization, data set, theme, entity and entity occurrence, and spatial relations.
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HTML
or
stdntdb3.pdf |
NTDB Data Dictionary
This document contains all of the entities that appear in the NTDB, together with their relations and other
pertinent information.
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dictntd3.pdf |
NTDB Metadata
This document presents the transfer format for the NTDB file metadata.
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HTML
or
metantd3.pdf
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Appendices
- Table of Entities, Combinations of Attribute Values, NTDB Codes, and Themes
- Bilingual List of Entities and Combinations of Attribute Values
- Table of Correspondence for Entities, Attributes, and Codes between NTDB edition 2 and 3
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appentd3.pdf |
Transformation of the NAD83 Datum for Certain NTDB Files
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Formats |
Conversion of NTDB files Using National Transformation Version 2 (NT v2).
This document describes the impacts on certain NTDB files after conversion with National Transformation Version 2.
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HTML
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ntdbnad83.pdf |
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