Dykstra’s Splitting and an Approximate Proximal Point Algorithm for Minimizing the Sum of Convex Functions

  • Chin How Jeffrey PangEmail author


We show that Dykstra’s splitting for projecting onto the intersection of convex sets can be extended to minimize the sum of convex functions and a regularizing quadratic function. We give conditions for which convergence to the primal minimizer holds so that more than one convex function can be minimized at a time, the convex functions are not necessarily sampled in a cyclic manner, and the SHQP strategy for problems involving the intersection of more than one convex set can be applied. When the sum does not involve the regularizing quadratic function, we discuss an approximate proximal point method combined with Dykstra’s splitting to minimize this sum.


Dykstra’s splitting Proximal point algorithm Block coordinate minimization 

Mathematics Subject Classification

90C25 65K05 68Q25 47J25 



We acknowledge Grant R-146-000-214-112 from the Faculty of Science, National University of Singapore. We gratefully acknowledge discussions with Ting-Kei Pong on Dykstra’s splitting which led to this paper. We also thank the two anonymous referees and the editorial staff.


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Authors and Affiliations

  1. 1.Department of MathematicsNational University of SingaporeSingaporeSingapore

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