Parameterized homotopy equations that define paths through the interio
r of the feasible region of a linear program are reformulated as gradi
ent mappings, and a standard symmetry principle for nonlinear equation
s is then used to derive associated potential functions. These functio
ns are the Lagrangians of weighted logarithmic barrier problems. Prima
l, dual and self-dual cases are considered, with emphasis on the situa
tion when starting points are infeasible. (C) 1997 Elsevier Science B.
V.