. . . . . . "A \"Position Vector\", also known as location vector or radius vector, is a Euclidean vector which represents the position of a point P in space in relation to an arbitrary reference origin O." . . "Position Vector"@en . . . . . . . . . . . . . . . . . . "http://www.iso.org/iso/catalogue_detail?csnumber=43012"^^ . . "\\(r = \\overrightarrow{OP}\\), where \\(O\\) and \\(P\\) are two points in space."^^ . . . . . . "http://en.wikipedia.org/wiki/Position_(vector)"^^ . . . . . . . . "r" . . . .