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Datums have been one of the most difficult problems the Group has dealt with. With the definition outlined, we feel we now have the problem under control. While our definition is not perfect, we can live with it. We are now in the process of expanding this definition to cover all aspects of datum use described in the Y14.5 standard.
Citation
Precision Engineering-Journal of the International Societies for Precision Engineering and Nanotechnology
Hopp, T.
(1990),
The Mathematics of Datums, Precision Engineering-Journal of the International Societies for Precision Engineering and Nanotechnology, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=821174
(Accessed November 7, 2025)