Hi, I am trying to find a lambda by the linesearch such that f([x_{k}+\lambda d_{k}])<f(x_{k})+\alpha\lambda grad f(x_{k})^{T}d_{k} where [x_{k}+lambda d_{k}] means the projection that cuts off the undershoot or overshoot of x_{k}+lambda d_{k}. How to add the above projection into the linesearch in PETSc? Thanks! -- ------------------------------ This message and its contents, including attachments are intended solely for the original recipient. If you are not the intended recipient or have received this message in error, please notify me immediately and delete this message from your computer system. Any unauthorized use or distribution is prohibited. Please consider the environment before printing this email.