Using the Moore-Penrose pseudoinverse, this work generalizes the gradient approximation technique called centred simplex gradient to allow sample sets containing any number of points. This approximation technique is called the generalized centred simplex gradient. We develop error bounds and, under a full-rank condition, show that the error bounds have order O(∆ 2 ), where ∆ is the radius of the sample set of points used. We establish calculus rules for generalized centred simplex gradients, introduce a calculus-based generalized centred simplex gradient and confirm that error bounds for this new approach are also order O(∆ 2 ). We provide several examples to illustrate the results and some benefits of these new methods.

Thank you to Dr. Warren Hare, my co-author and supervisor. You have inspired me and helped me become a better researcher. Thank you to NSERC and UBC for funding this research. x Dedicatioǹ A mes parents: Merci pour tout ce que vous avez fait pour moi. Merci d'avoir continuer de croire en moi malgré toutes ces années difficiles. Merci de m'avoir apprisà ne jamais abandonner. Je ne pourrai jamais assez vous remercier.

No abstract

No abstract