Title: nonlinear mapping Long Title: IUPAC Gold Book - nonlinear mapping DOI: 10.1351/goldbook.10102 Status: current Definition Projection of objects defined in a multivariate space onto two- or three-dimensional space so that the distances between objects are preserved as well as possible. Notes 1) An often applied criterion for the mapping error (\(E\)) is the relative squared error between the true distance \(d_{ij}\) and mapped distance \(\delta_{ij}\). 2) Several iterative optimization procedures can be applied to minimize \(E\), such as steepest descent. Source - PAC, 2016, 88, 407. 'Vocabulary of concepts and terms in chemometrics (IUPAC Recommendations 2016)' on page 422 (https://doi.org/10.1515/pac-2015-0605) Other Outputs - html: https://goldbook.iupac.org/terms/view/10102/html - json: https://goldbook.iupac.org/terms/view/10102/json - xml: https://goldbook.iupac.org/terms/view/10102/xml Citation: Citation: 'nonlinear mapping' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.10102 License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. Collection: If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. Accessed: 2026-08-06T06:44:43+00:00