比如求资产组合各类资产的权重,除了对单个权重要介于(0,1)之外(这个可以用lower = -Inf, upper = Inf来约束),还要求所有权重之和sum(w)也要介于(0,1)之间,这个怎么实现呢?
optim函数及参数如下:
optim(par, fn, gr = NULL, method = c("Nelder-Mead", "BFGS", "CG", "L-BFGS-B", "SANN",
"Brent"),lower = -Inf, upper = Inf, control = list(), hessian = FALSE)
非常感谢~