Necessary and sufficient conditions for the nonnegativity of a generalized inverse of a linear map between vector spaces are given. This includes a characterization for nonnegative matrices. Relations to the nonnegativity of the Moore-Penrose inverse, the group inverse and the Drazin inverse are discussed.

K C Sivakumar

Department of Mathematics

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

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Journal	Indian Journal of Pure and Applied Mathematics
ISSN	00195588
Open Access	No