If you have data gathered in one coordinate system and want to express them in terms of a different coordinate system, you probably would use a translation vector and a rotation matrix. You can, ...

HAVING a vivid recollection of the pleasure I derived born Prof. Gibbs's attacks upon the quaternionic system in the rather one-sided discussion that took place about two years ago in this journal, I ...

IN a paper by Prof. C. G. Knott on “Recent Innovations in Vector Theory,” of which an abstract has been given in NATURE (vol. xlvii. pp. 590–593; see also a minor abstract on p. 287), the doctrine ...